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What's the point?

Discussion in 'Intermediate CJ-5/6/7/8' started by ReLoaded, Dec 23, 2008.

  1. Dec 25, 2008
    mcgillacuddy

    mcgillacuddy Member

    Kalama, WA
    Joined:
    Nov 14, 2007
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    316
    If you're looking for some more input on this, I'll weigh in.
    As an owner of two CJ's, one with a box stock 304 and another with a box stock 360 and as an engine builder for a living...I will give you my thoughts on it.

    First the 304...There is nothing wrong with the 304. It does what it was designed to do. In off-road situations (not racing) a stock 304 will have nice power. It will be a rare occasion when you won't be able to make it somewhere because of the stock power of a 304. However...it sounds to me as if you may be looking for a little more power from your engine, and that can be done to a 304. You can go with larger valves, bigger cam, good intake, four barrel carb, hotter ignition, more compression, the list goes on, but you get the point. The thing is, the more of this you do, the less like a good Jeep engine this becomes. Well, I guess I should not say that, if the way you off-road is mostly high rpm wheel speed, then it would be a fine engine for that.
    In my career I have build a few 304's for AMC cars. They can be made to run pretty hard, but as most small cube engines, once you start building high power, you lose low RPM power. Not really a good thing for "most" Jeep guys. If you just want to install a mild cam, a set of headers, a small four barrel to your 304 and not get into big valves, high compression...then you will notice a power increase across the board and it will be a good little engine.

    Now...lets talk about the 360. Forget about the HP number difference you read about between the 304 and 360. The only way you could possible understand what I mean by that would be to climb out of a CJ with a stock 304 and get in a CJ with a stock 360 and go for a drive. The difference is nothing short of astonishing.
    Let me put it this way...to make a 304 run like a stock 360 with take a lot of work, and even then, after all that work, it still won't have that brutal low end torque of the 360. I wish you were closer to me, I would gladly let you take a drive in both of my Jeeps. Guys here that have replaced their 304 with a 360 know what I am talking about, it may just be one of the "you have to experience it for yourself" kind of things.

    I sand drag as a hobby and have a Jeep built for that very purpose (avatar) but one time I decided to race my trail rig just for the fun of it. Now this is the one with the bone stock 360. The only thing that had been done to this 360 is a set of headers, the rest is stock and at the time of the race, it had 131,000 miles on it. Also known as wore out.
    This thing idles smooth (stock cam) has tons of low end for crawling around and in it's worn out, high mileage state, cracked out a 4.88 100 yard pass in the sand and it packed the front tires for a fare share of the 300 feet. Can a 304 do that? Sure, but it sure in the heck will not be stock with over 100,000 miles on it.

    [​IMG]

    [​IMG]

    A short word on HP numbers...I won't turn this into a huge technical blabbering....But...peak HP numbers (in the real world) are over shadowed by how the engine got to those numbers. I have a Dyno in my shop. I can tell you that there are many cases where an engine with a lower peak number will outrun one with a higher peak number in a race....Because it will make more power and torque throughout the entire RPM range as apposed to a lot of power just in one spot.



    I guess what I am saying here is if you are really looking for a power upgrade (a big one) and a fairly cheap one, a 360 is the way to go in my opinion.

    If you just want to pick up a little zip from the 304, a few add ons will make it run pretty okay. If you have plans of tearing the whole 304 apart and doing all sorts of performance work to it, then you are going to have a lot of money and time into an engine that would be out powered by on old 360 that someone put a cam and after-market carb on (generally speaking of course).

    In the end, it's all up to you and the best way to make an informed decision is with as many facts as you can gather. My suggestion would be to try and talk to as many folks as you can who have done a 360 conversion. And if you're lucky, maybe one of then will let you take there 360 for a short spin. Then you can really have some good info to go on.
     
  2. Dec 25, 2008
    jinpdx

    jinpdx Member

    Caldwell, ID
    Joined:
    Feb 5, 2008
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    121
    Theres nothing better than making alot more power for as little money as possible. That being said, if you put the money that your gonna put into that 304, and put it in a 360, then look out, you'll have a beast on your hands. I don't see the point in spending alot on a little motor, just to try and make it perform like a stock motor thats just alittle bigger. 360's can be had for little to nothing for a rebuildable core, and as little as a couple hundred bucks in good running condition. It seems like a no brainer to me. Of couse, I went from a 304 to a nicely built 401, so... I guess I'm just power hungery.
     
  3. Dec 26, 2008
    mcgillacuddy

    mcgillacuddy Member

    Kalama, WA
    Joined:
    Nov 14, 2007
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    316
    Oh yeah...if you can dig up a 401, they are a beast. The 401 is not rare by any means, just not everywhere like the 360.

    One things I wanted to mention in my previous ramblings but forgot, is the factory horsepower rating for the 360 and 304 in those years where "net" not "gross". What's the difference you may wonder?
    Well.....Back in the early 70's (I think 1972) all manufactures changed their rating to "net". This new rating was brought on by the society of automotive engineers (SAE). The old way of determining horsepower (gross) was to stick on engine on a dyno with no air cleaner, open exhaust and absolutly no accessories running on the front of the engine. No alternator, power steering pump, nothing, they did not even run the water pump, they just pumped in water themselves. So it was the MOST power you could get in a best case scenario.
    Now...SAE changed the rules on that deal and said that all engines must be tested with all their goodies running...Even air condition pumps. Full air cleaners, full exhaust, the works.
    This is one of the big reasons why a 360 and 304 are not very far off in the numbers. The 360 was tested with a small diameter pipe, running through a single muffler. It was pretty much smothered and not allowed to breath like it is capable of. The heads on an AMC 360 flow some amazing number in stock form. Like close to an LT1.
    In an extreme example....if you took my sand drag jeep's engine (which is 809 hp) shoved a stock air cleaner on it, and ran it through a small tube single muffler, it would probably croak off at around 300.
    This is one of the big reasons why people just cannot believe that the 360 and 304 are close in HP numbers after they drive a 360. Most of the time, a CJ with a 360 swap has better flowing exhaust, air cleaner, carb, etc...Which makes them able to get a deep breath.

    "edit" And I almost forgot...the maximum overbore for an AMC 304 is .125 that's 3.75 to a 3.875, which will make it a 324 cube (and change). This should only be attempted if the block is sonic tested and the shop gives you the okay, because not all of them will handle the 1.25 overbore.
     
    Last edited: Dec 26, 2008
  4. Dec 26, 2008
    avmechanic

    avmechanic Gearhead

    Langley B.C. Canada
    Joined:
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    Check out this thread about 304 camshaft choices. http://www.earlycj5.com/forums/showthread.php?t=61162 I made a couple of posts with suggestions. My opinion for you application would be to leave your good short block alone. Send your stock heads in for a rebuild, including a 3 angle valve grind. If you need new valves go for some slightly over sized. Your machinist should know what is available. You can deck the heads for a mild compression increase. If you have a die grinder and are handy with it, I would do some port clean up including some minor bowl blending behind the valve and portmatch the intakes to match your gaskets. Clean up any casting flash or irregularities in the runners that you can reach. It is quite easy to do and is just common sense for airflow. If you don't know what to do for advanced porting do not try to drastically change any ports or runners. There is no way to screw up with just basic cleanup. Do all of this before you give the heads to your machinist for their rebuild. Some mild head porting can be a fun project. Just pull the valves and springs and go for it. Once you have your heads done drop them on your short block with a good cam, performer intake, four barrel of your choice, and some fender well headers with exhaust. You will end up with a good performing 304. For cam selection check out the suggestions in he thread I left the link for. If you didn't have a good short block I would say just do a complete build of a 360 but in your situation I think the 304 will perform great for less time and money.
    Greg
     
  5. Dec 26, 2008
    mcgillacuddy

    mcgillacuddy Member

    Kalama, WA
    Joined:
    Nov 14, 2007
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    I think he started this thread asking why not rebuild his 304 instead of go with a 360.
    Since he is rebuilding it...the time and money are kind of a wash with going 360.
    Tell you guys what...For my CJ-5, I just found a Cherokee that was rusted out. Started it, took it for a drive. It ran great, had good oil pressure (for an AMC with close to 100 K on it) gave 500 for the whole thing. I boned out the rest, sold the good stuff on Craigslist and had a good running stock 360 for free (Plus labor). I dropped it in one weekend, and have not done anything but maintenance to it since.
    Now...this is not a "lucky find" these things are everywhere. There was a 401 on craigslist the other day for 600 bucks (It is now in my shop):)
    But, if you want a totally fresh engine. 360's that need rebuilt can be gotten for 250 to 300 bucks. So that's an extra 300 on top of your 304....I can promise you that it will take A LOT more than 300 dollars to try and get the 304 to run with the 360. That's what's cool about the 360, you can leave it mild and it will still honk.
    However....there is no reason not to run a 304...I mean, I cannot give you a good reason, they are a good motor. I guess the point being...on a total rebuild, you are going to be out close to the same money and have more power with a 360.
    304, 360 and 401 parts cost basically the same. You already own a 304 block is the difference. But as mentioned, the price of a rebuilder 360 is really nothing. AND, you could drive around your Jeep while you were rebuilding the 360...There is something to be said for that right there in my opinion.
     
  6. Dec 27, 2008
    ReLoaded

    ReLoaded Professional Drunkard

    Santa Ynez, CA
    Joined:
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    Wow, Lots of great feedback here! Took me a fair bit to read it all! Let's see, I think that McGilla has a great point here. I agree the 360 by far out performs the 304 and I would have no qualms about tossing one in, but the only ones available in my neck of the woods run about 600-750, which I personally think is outrageous! I have seen a couple 401's for sale for about 100 or so less, which is odd, but I am a bit intimidated by the terrible gas mileage I have heard these things get. I'm sort of looking for something in the 300-350 hp range, more for fun than anything. I don't do much extreme offroading just some mild trails and general fun at the beach. I am pretty sure an 401 would be vast VAST overkill in my case, I don't want to have to install a 20-30 gallon fuel cell just to take a bit of a drive you know? I was just curious why a ford 302 swap is so popular and 304's are not, I thought that maybe the 304 was capable of being at least as good after all I have heard about AMC's heads being able to breathe better and whatnot. I wanted to keep it all AMC, just get a little more pep out of it. Maybe a 360 would be ideal, but could one be built to have fair performance and still get at least 12 mpg avg? To this day I can't understand why SBC's can be built to the same numbers and get better mileage, but I still don't want to swap. (by the way Mcgilla, those are some badass pics!)

    I suppose i have some soul searching to do! I appreciate all the feedback on this, it's probably the most respose I've gotten anywhere! Thanks!

    Brian
     
  7. Dec 27, 2008
    mcgillacuddy

    mcgillacuddy Member

    Kalama, WA
    Joined:
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    Hey Brian...
    If you want 350 hp (a TRUE 350) out of a 304 and want some mileage too, it's not going to happen. A 350 horse 304 is a radical 304. Big cam, big heads, high compression, big carb. And A LOT of work. It would be very "twitchy" like gutless down low, then all power up higher.
    The 360 in my blue CJ pictured gets 12 MPG with 33's and my jumping on the throttle a lot. I could get it higher if I wanted to drive normal. So, it's terrible, but about in the ballpark of what many get.
    302 is popular because it's a pretty good engine, it can be found in abundance and one of the real biggies is it's physical size. It's very short.
    I know that the displacement of a 302 Ford and a 304 AMC are very close and this is where people get sort of confused. Sure...cubic inches do mean something, but other that that, these are two very different engines.
    Just if you go by bore and stroke, the 302 Ford has a 4.004 inch bore with a 3.0028 inch stroke a 304 has a 3.75 bore with a 3.44 stroke.
    HOWEVER...that is not the reason you cannot build a 304 to run with a 302...Actually, you CAN...but you're going to be very involved and you're going to have to deal with guys like me all day to get the work done (and know one wants that:)). The reason is... what is available in the after-market and the amount of research that has already been done to make horsepower from a 302. The 304 does not have that size of a following.
    I'll tell you what though, if you make a direct comparison to an old carburated 2V (two barrel carb) 302 Ford from the 70's, taken in "NET" horsepower. They have 141 horsepower. Not exactly top fuel material huh? But these days, you can go grab a wrecked crown vic out of a yard with a 302 in it...it has fuel injection, a roller cam, good ign, etc...and that is in stock form.
    I feel that if AMC had become an industry giant like Ford or GM...the AMC engines we would see in late model cars would be similar (maybe better).
    Moving on to the small block Chevy....
    The small block Chevy is the most love and most hated engine in the world. People love it because it's a great engine. It really is, I mean, there is a group of guys that will tell you it's junk, but it's not. The after-market is almost geared AROUND the SBC. It's a good design engine, that makes good power and is reliable. Which is the big reason for it's popularity.
    Most of the reason it's hated is the same reason it's popular. EVERYBODY has one. I don't know if your a "car guy" or not, but if you go to a car show and are looking at hot rods....you see small block Chevy after small block Chevy, the next guy opens his hood, it's a small block chevy and you think to yourself "wow, small block Chevy, never seen that before". But then there is a guy with a Hemi, or an old FE Ford, a nail-head...the list goes on of alternatives.
    You say you're going to leave it AMC, which I feel is good. But if you WERE going to an SBC...I really would have no good reason why you should not. The only thing I could come up with is if you want to use your tranny, you will have to buy an adapter. Some contend that the AMC builds more torque at lower rpm than the SBC...Which for the most part is true.
    I won't be posting a bunch of dyno charts and graphs here, but, I have found that when you compare the same "style" engine (low rpm torque) the difference between the 360 and a 350 is negligible (this statement does not include the 401).

    Anyway...back to the point, if the only thing holding you back from a 360 is bad mileage, don't let it, it's not that big of a difference, especially if you build a hot 304...the 360 will probably get better MPG.
    About the price of a 360...Even here, I would say that they "average" 500 to 700 bucks, but....if you make it a habit to check Criagslist every day, you will come onto a cheap one. Also...many times it's cheaper to buy the entire vehicle instead of just the engine.
     
  8. Dec 27, 2008
    avmechanic

    avmechanic Gearhead

    Langley B.C. Canada
    Joined:
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    I was thinking he had a good shortblock that he didn't want or need to mess with. After reading his posts again I realized he still wanted to rebuild the bottom end as well. If you are going to be doing everything anyways, you are right. You might as well start with a 360 for a complete rebuild. If on a tight budget look for a runner 360 and just clean it up replace any leaking gaskets and stuff it in. If a little more budget is available do the same kind of things I recommended for the 304. A mild cam, performer intake, fenderwell headers and a four barrel carb. Use a adapter for a quadrajet carb and you can end up with a good offroad carb as well as they can help with mileage if you can keep your foot out of it and run around on the small primaries. I had used an adapter to a old edelbrock sp2p intake to a quadrajet on a 304 for a friends jeep and it ran great. I am not sure but the performer might even be available with the dual bolt pattern carb flange to make it even easier.
    Greg
     
  9. Dec 27, 2008
    ReLoaded

    ReLoaded Professional Drunkard

    Santa Ynez, CA
    Joined:
    May 24, 2008
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    Actually the bottom end looks fine, but I was going to pull it just to clean it up and throw some bearings/rings on it. A 360 would be a nice build obviously for more power, and while I'm not really THAT concerned with costs, I would hate to have like a 100 mile range or something...I've already got a rebuilt Quadrajet, a Performer intake that I got for free, headers, and an edelbrock cam. I guess I just don't understand why that 304 is such a slug! Shouldn't it be fairly easy to produce 1hp/ci? I mean, I may be new to AMC powerplants but I've got a bit of a history when it comes to hotrodding random vehicles around the house..

    So what is the practical power ceiling for the AMC 304? Maybe I'm just expecting too much out of it..I understand the theory of stroke to bore ratios and all that but shouldn't the 1.09 ratio mean also that the 304 would produce more torque than a ford 302 with a 1.3 ratio?

    I guess i can't just wrap my mind around the fact that the 304 is really THAT much less powerful than the 360, I mean I can see the torque advantage on account of the displacement but comparable models were about 15 hp apart. I know McGilla mentioned that the 360 was tested with suffocating equipment, but then wouldn't the 304 have been tested in a similar fashion? It seems that they were never too far off in the ratings in any given year, unless you count the models with 4 bbl carbs vs the 2 bbl versions.

    Can someone explain to me why these motors cannot be built to have 1hp/ci for about the same price it takes to get 400 hp out of a 360?
     
  10. Dec 27, 2008
    Psychojeeper

    Psychojeeper Aint 'sposed to be pretty

    Las Cruces, New...
    Joined:
    Nov 15, 2005
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    368
    As I see it ,, it's a cost thing.It would be more cost effective to get power and torque out of an engine that is larger and puts out more power to start with in stock form. Throwing 2 grand into a 304 will get you the same power that putting 700 or 800 $ into a 360 will get you.

    same thing if I really wanted a lot of power in my Jeep, sure I could dump a ton of cash into the 5.0/302 Ford I am running, but it would be more cost efficient to just find a donor vehicle with a good running 351 that in stock form puts out the HP & torque ratings I am looking for.

    SO,, 2,000 to 3,000$ for hot-rodding a 304 to get it to the power level you want, OR 700 - 800$ for a stock 360 with the same power rating. Seems simple to me. OR,, to put it more bluntly, why pay to beef up a small engine when a BIGGER stock engine can be had for less cash. I have never paid good money to beef up what I had, instead I paid to upgrade to a larger more poewerful motor,,, if I hadnt ,,,, I'd be running a high-dollar 151/2.5L 4 cylinder instead of a fuel injected 5.0.

    May as well ask why not build a 396 instead of swapping in a 454. If the bigger motor is a dierct swap-in & bolt-up,,,, why waste time with the smaller motor. If all you are looking for is to freshen up the 304, go for it, you will notice improvement, but if you want big change you have to go big.
     
    Last edited: Dec 27, 2008
  11. Dec 27, 2008
    mcgillacuddy

    mcgillacuddy Member

    Kalama, WA
    Joined:
    Nov 14, 2007
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    I did not wish to mislead you and suggest that a 304 is an unbuildable dog of an engine. Your want for 1 hp per cube can be done for about the same cost it will take to get 400 out of a 360. But, where you build that power will be in a different rpm.

    So lets just say that you tell me that you want a little over 300 out of your 304 but you want low rpm power too. I would tell you no problem, but you're going to have to mix race fuel with your pump gas, because I am going to raise the compression to a level that will not be very friendly. Or I will suggest a turbo 304, where I could give you 500 plus HP.
    The problem lies in that it's sort of a low rpm engine by design. A low rpm engine is fine with a few more cubic inches to move it, but a low rpm engine with small displacement is going to take some work to make run hard.

    To be flat out honest, I am not at all thrilled with the cam choices out there for AMC...So I would custom grind you a camshaft, raise your compression, change the combustion chamber a bit, the valve train geometry...the list goes on...I could build you a 350 to 400 hp 304 that had low end power. But...at what cost. This involves a lot of parts made by me....so it's going to go flying past 5 grand like a freight train.
    Really what I am doing is changing the total design of an engine and that is not easy.
    Now....remember, torque is really what you're after in a Jeep. You can have that in a 304.
    Oh and the reason the the number come close to the same on a 360 and a 304 on the dyno...is that the 360 is choked VERY badly and the 304 is just choked a little. The 360 is larger, larger valve, etc....so restrictive stuff on a 360 has a bigger effect than restrictive stuff on a 304.
    So it brings them closer together.
    If you are not happy with the power of your 304....it most certainly can build more...at a high price.
    Or...cave in and do it the easy way with a 360. Both can be done, one is just more difficult and more expensive than the other.
    I actually admire you for thinking "outside the box" a bit. I love taking things that are not supposed to be fast and making them that way. Hell...I'm just finishing up a customers hot rod engine this evening that is a straight six Chevy with a progressive twin turbo set-up. It will be cool and different. So I applaud you if you really want to build the 304. I'll even help you with it all I can. But I sure would like you to take a drive in a 360 powered rig before you take the plunge...then make up your mind.
     
  12. Dec 28, 2008
    ReLoaded

    ReLoaded Professional Drunkard

    Santa Ynez, CA
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    I guess what I'll do is rebuild the 304 as solid as possible for now and when i get a shot at a decent 360 in the area rebuild that on the side. That way it'll be a drop in affair. I'd guess that getting 1hp/ci out of a 304 would give me around 230 rwhp? That would be plenty I think for me in a 2500 lb CJ. So McGilla, what all would you recommend doing to get 1hp/ci out of the 304?
     
  13. Dec 29, 2008
    mcgillacuddy

    mcgillacuddy Member

    Kalama, WA
    Joined:
    Nov 14, 2007
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    Okay...I'll give you a rough outline.
    I would like to reiterate that is will not be a low end torque, putt around, type engine. It will have a fairly hairy idle, throttle response will be more explosive than smooth and it will really start to rock and roll at around 3,200 rpm. It won't be a complete dog under 3200, but it won't be a tractor either.
    Since you said you have had a hot car or two, I figure I am not talking with a guy who does not know what he is getting himself into and can probably drive a higher RPM engine. I have buddies that LOVE to run sprint car style engines in their pickups. 8000 rpm plus is just fine for a four wheel drive to them.
    Lets start at the top. You will need a good carb. Normally I would recommend a 470 truck avenger, but your going to want more than that. The next step up is the 670. These can be tuned very well and work terrific. There are a lot of intake manifolds to choose from, but unfortunately, there are only a handful of them for AMC that cost less than my first home. I would recommend an offenhauser 360....it's a single plane, but is has a split plenum. I have also run the performer RPM which is a dual plane and works fine, but the cam I am going to recommend works better with the offenhauser. You won't need to go too fancy with the ign, just one of the Chevy HEI style coil in cap. They work great. Get a good one though, there are some cheap ones that I have heard of having problems.
    Heads...The sky is almost the limit here. You can buy a set of the Edelbrock aluminum heads for it....These are made for a 360 or 401 because the valves are too big for a 304...But the right shop can put in smaller valves. I know, it seems a bit silly buying a head and going to a smaller valve, but what we are really after is the combustion chamber design and the fact that it deals with higher compression better. If you do go that route. The heads can still use a little time on the flow bench in my opinion, there are plenty of guys around your area that can do some work on them to match the cam.
    If you wish to skip the edelbrock heads and keep the ones you have. They will obviously need to be rebuilt. Go with a 1.94 intake valve and a 1.60 exhaust. Have the combustion chambers matched, cleaned up, same rules apply to the flow bench work. They will need to be cut for the valve springs that will come with the cam And will be set up for roller rockers.
    The cam will be a custom ground roller (I can give you numbers, or you can have me grind it).
    The "STATIC" compression ratio will be 11.3 to 1...yes, that sounds high, but it's not that bad, because the DYNAMIC compression ratio will be much lower....The cam grind will take care of that.
    You will bore you block to whatever size is needed to clean it up (probably 30 over) the block will be zero decked and will run a quench area of 35 to 37.
    Good quality header with a nice dual exhaust.
    The rest is almost all about making it hang together. Balancing, shot peening, addressing some oiling issues, cam walk, Head bolts, main caps, forged pistons. You may have a hard time finding the perfect piston, but you can have a good shop make the right set out of blanks. I don't recall if you said what you were running for a trans, if it's an auto, you will need a stall converter.
    Again this is just a rough outline, but gives you an idea what direction you need to take.

    Another way (and no I'm not kidding) would be to build the engine for forced induction. This would keep the cam and heads very mild. You would need quality pistons and all the lower end goodies I mentioned...but this could be a nice streetable engine that idles smooth and would go right on past your 1 hp per inch with a little boost. You will need a custom headers built (or build them yourself, not sure of your fab skills) Two, small, properly calibrated turbos, blowing into a carb (set up for pressure) will make a beast. I have been building turbo charged engines for many, many years, and turbo lag is nearly non existent these days, so if that is something that interest you, I would be glad to help out there as well.

    Is your current 304 shot? Like is it in need of a rebuild very badly, or could you run it a bit longer? If so, I would (just an opinion of course) I would put a small four barrel with a performer intake, a set of headers and maybe a small cam in it and run it that way while I put together a 360.
     
  14. Dec 29, 2008
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    Just a comment - have you driven this Jeep a lot? If not, you might want to drive it a while and evaluate what you need. If you go to Pismo a lot, you'd see some advantage in the 360. However, you might see even more advantage with a transmission change, and specialized tires. Back in the day, the close-ratio 4-speed conversion was very popular for dune runners.

    If you are going to mostly go east, toward the mountains and desert, there may be better places to put your money and effort. It was long ago, but I found the 304 with 4.27 axles to be plenty of power for desert trail riding.

    What are your compression test readings? Specifically, why do you think the bottom end is solid but you are considering rebuilding the heads? If you have good compression and good oil pressure, swapping out the engine would not make much sense for most people.

    All this discussion of engines is great, but remember that, when it was introduced, the 304 was considered (by many) to be too much engine for that chassis. Having a lot of power will be exciting, but it may not do much else for you other than give you bragging rights and get you into trouble that much faster. Do you know about the law of diminishing returns? IMO you're pretty far up on the curve with the 304 already. More power will be better, but maybe not as much as you expect.

    There's a group-think promoted by some media, aftermarket sellers and some peer groups (ie Pirate) that tells you to buy the biggest and baddest mill, gears, axles, or whatever that you can shoe-horn into your Jeep. This is the BS element about the 304 and 360, and I think that's what you detected that prompted your original question. I think it will be worthwhile to actively screen out peer pressure in this area, and instead consider your needs coolly and logically. Jeeps are amazingly competent trail vehicles in stock form, and you should be proud of what you have for what it is. JMO - put it together and drive it / wheel it / enjoy it.
     
    Last edited: Dec 29, 2008
  15. Dec 29, 2008
    mcgillacuddy

    mcgillacuddy Member

    Kalama, WA
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    316
    I don't want to speak for Brian here, because I do not know his feelings on the subject. Maybe he will share why he wants to do what he wants to do with us.
    I personally did not get the feeling that Brian was questioning the capability of the Jeep with a stock 304. Most of us in here know that a Jeep with a stock 258, the right tires, gears, etc will go close to as many places as something with a hot motor. In some cases they will even go more places.
    There are really just two types of people when it comes to cars. Neither or right or wrong, just different. An easy example would be to take a car that we all know....The Chevy Nova. The Chevy Nova was available with a straight six. This is a fine engine, it will take you anywhere the roads are paved. You can drive from coast to coast and it will not miss a beat. It runs smooth, will get you to the store and back, will do the posted speed limit and will last a long time. Yet....Chevy offered the Nova in a 375 horsepower, 396, big block. There were many who just do not understand why anyone would want such an engine. It was a gas gulping, loud, solid lifter engine that was not as reliable or smooth as the old straight six that would get you just as many places as the 396. Not only that, the 396 actually cost more at off the lot. Not only did people buy the big block Nova, many of them would modify them even more, for more power. The Nova was overpowered as it was. This is a uni-body car, so it was already trying to tear the car in half. Why the heck would anyone bother with this nonsense?
    Most who did not understand why... figured out that it is just nothing more than bragging rights. No one would ever want or need such a car unless he/she was trying to make up for some sort of sort coming or was just trying to impress people. This sort of thing may indeed be true for some of the people who bought these kind of cars.
    But...then there are the type of people that just LOVE power. That feeling and that sound become something they just can't get over. They want it in pretty much everything they drive. These people are not trying to impress anyone but themselves. As a matter of fact, if one of these type of people were the very last person on planet earth and had the choice to jump in any car that he/she wanted to... and drive off....They would not choose the bone stock Ford Granada. They would get into something that had a massive amount of power and run it hard...even though there is no one around to impress.
    It's much the same way as owning an old Jeep. Why the heck do we do it? Lets face it, they are loud, they don't handle all that great even in perfect form, by today's standards, they are rough riding, windy dinosaurs that many consider unsafe at freeway speeds. They are not even cheap these days. So when you buy an old Jeep, you are generally looking for an old Jeep. Even still, I love to drive my Jeep. I get exited when I know I am going to take it somewhere, especially on a nice summer day when I have the top off. There is no praticle reason to have a old Jeep these days. It's fun to us and would be nothing short of hated by some others.
    Some of us like are Jeeps the way they came, some of us like to change them (whether it for better or worse). A Jeep is just one of those things. you get or you don't. Wanting a massive amount of power for no real reason is just one of those things you get or you don't.
    Be it right or wrong, it's just a personal preference. I kind of get the feeling that Brian may be one of those guys who likes power in whatever he drives. He likes his Jeep and he likes power, if he combined the two, maybe he will like it even more.
     
  16. Dec 29, 2008
    bobo

    bobo Sponsor

    canby or
    Joined:
    Aug 12, 2008
    Messages:
    69
    I love this thread! Great writes up and oh! so true, This forum is Filled with great knowledge. Go guys go :):)
     
  17. Dec 29, 2008
    ReLoaded

    ReLoaded Professional Drunkard

    Santa Ynez, CA
    Joined:
    May 24, 2008
    Messages:
    94
    I'll be honest with you for a minute here. I didn't buy this jeep for off roading, that was a happy coincidence, I bought it mostly because it was pre-smog. I planned from the start to mod the hell out of the engine, but plans changed when I discovered how much fun it was on some of the trails in the area, so more money was allocated to it's off road capabilities. Although I still think that the Jeep makes one hell of a...Well..Jeep. I'd like it to be somewhat of a more entertaining Jeep. I love being in the open air, I love the sound of it, hell I even love it's small size. I love it so much, my previous driver (LS1 Camaro) has about an inch of dust on it..

    I'm not really looking for bragging rights, it's more of a fun thing. I agree no one should be peer pressured into modding a jeep half way to hell, I'm just looking for a bit more juice out of the current mill. I mean, if it's at all possible to get more out of what I got, that's what I'd like to do. I'm not a big fan of swapping, but I am a big fan of customizing. My Camaro is pushing about 400 to the wheels, my Girlfriends Rabbit is close to 220. Hell I think the Jeep ought to be able to out power the VW...

    It's like tool time over here at my house..Sh*t blowin up...The whole nine.

    I've never built a Jeep in my life, but I figure it can't be THAT much different. But hey, you guys are the experts, so I'll take what i can get. If all else fails I have a Buick 350 I could use...But I'd really rather buy a decent 360 than go changin makes and what not. Problem is, no decent 360s in the area. Hell, if I wanted crazy power, I COULD use the LS1, but that's just not the plan.

    Timgr, I appreciate your concern! That's one of the great things about owning a Jeep, it's like a brotherhood. I have indeed driven it as she sits for a good bit and decided to tear it down for a rebuild and possibly more power. Eventually if the opportunity arises for a 360, I'll most likely rebuild it on the side. For now I'm just looking to get what I can out of what I got.

    http://i292.photobucket.com/albums/mm1/brianshaw86/Camaro.jpg
    http://i292.photobucket.com/albums/mm1/brianshaw86/DSC00828.jpg
    http://i292.photobucket.com/albums/mm1/brianshaw86/DSC01387.jpg
    http://i292.photobucket.com/albums/mm1/brianshaw86/DSC01430.jpg
    http://i292.photobucket.com/albums/mm1/brianshaw86/DSC01432.jpg
     
  18. Dec 30, 2008
    CJ Glen

    CJ Glen New Member

    Northern California
    Joined:
    Jan 14, 2008
    Messages:
    48
    I also love the expertise you AMC guys share here.

    I had my stock 304 rebuilt to stock again, and although it is not a race engine, it scoots fine on the highway. I don't know that the stock Dana 30/ 44 axles could take much if the 304 was built. I only wish it was fuel injected, and a 4 speed trans would be nice. In low range, I don't see where a whole bunch of torque beyond the 304 would be needed, unless you want big tires.

    ReLoaded, is the Camaro in your link the one you are talking about? It looks like an LT-1 car, not an LS-1 car. Did you go retro on the wheels? And roll up that window! :p
     
  19. Dec 30, 2008
    ReLoaded

    ReLoaded Professional Drunkard

    Santa Ynez, CA
    Joined:
    May 24, 2008
    Messages:
    94
    Na, wheels were there when I got it. Never felt the urge to change, although you aren't the first to notice haha

    LOL I'd roll up the window but then...Where would I put my boat stuff? Then, I might actually have to find somewhere else to put it..and it doesn't look like that's on schedule haha
     
  20. Dec 30, 2008
    CJ Glen

    CJ Glen New Member

    Northern California
    Joined:
    Jan 14, 2008
    Messages:
    48
    I know about people and wheels. We bought a '98 Suburban with stock Escalade wheels on it. Hat e 'em, but buying wheels with so many other demands is not on the radar. We get teased plenty.

    I'd offer for you to keep your Camaro next to ours, but we are out of room too.R)
     
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