I want more power

Mercury136

New member
So I've been looking into upgrading my engine for more power. Reading online about all the different options for pumping up a chevy 350 has me drooling a bit. Perhaps I shouldn't be reading on summit racing forums and the like but c'mon, converting a 350 to a 408 ci stroker pumping over 500 hp? is that overkill? Iv got a heavy duty clutch, pressure plate, transmission but everyone I talk to about it shakes their head and says "no no...you don't want to do that, blah blah...put the money in your axels, put the money here and there, you don't need more power. I get myself all exited with ideas and everyone shoots me down. Most of the people Im talking to are far more mechanically experienced than I so I assume they know what their talking about. I don't know, I guess Im just hoping someone will jump in here and cheer me on....Well?
 

A CJ5 is light and agile, you don't need gobs of power. A stock or mild v8 will be plenty.
 
I totally Agee that a good running V8 , even a V6 will be suffice . A guy at my job who sold his CJ YEARS ago because he grew tired of pumping money into it . He was told to settle for a good runner V8 or prepare to load it up with after market promises of added HP and durability. While the engine only produced 400 something hp and close to this in torque, it was enough to tear up engine and trans mounts like clockwork and a second fractured bell housing and input shaft on the AX15. He really pioneered it well but thought Tim Taylor's " MORE POWER !!!! ARRRR!!!!!" Was the answer for hill climbing. Personally , we must rethink when we purpose build as we must dress for success our jeeps to perform AND survive. Dependability or performance ? I was thinking some time ago ( pre- Jeepz.com days) why can't I put a 4.6 ford expedition engine in a CJ ? I wasn't asked to leave but reminded if jeep wanted that much power in a small package , it would have been born with it. The guy told me of his jeep CJ w/small block story and said " you want more power ? Buy a bigger truck ! " . I trusted him. I trust Bounty_hunter too , if a 350 2bbl can light up the tires on a '75 Monte Carlo , it will move a jeep adequate . Last longer too .
 
Well I guess I should be smart and take everyones word for it. Longevity... the last thing I want is to spend a ton of money in engine upgrades and rip the rest of my jeep apart. My friend who helped me assemble and install this engine tell me if I want to get the most out of this engine I need to get rid of the ancient tech of "points and condensors" and get a MSD ignition and have someone who is a wiz with timing and carb tuning set it up. He did the timing/tuning by ear himself and it runs good but he keeps saying it could run better. Anyone familiar with high performance ignitions? They fairly simple to set up?
 
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You should look into the 3.9L 4bt cummins swap i have been wanting to do this for a good 2 or 3 years just don't have the funds.
 
I have a chevy 327 putting out about 350hp and used to brake trany mounts everytime I got on it hard. Got tired of buying mounts and solid mounted the trans and havnt broke any mounts yet, the motor was solid mounted instead of using motor mounts too, I have had to take the engine brakets off and weld up cracks in them from hotroding it on the street. You do not need this kind of power in a jeep in my opinion, the engine and trans were there when I got mine so, they stayed. I have found that off road it is not real good having that power, just the slightest touch of the peddle and you are spinning tires (not good when you want traction). It is a blast though flooring it on the street, but with the short wheel base there is a lot of torque steer. You could put a cam in it and gain some power but still not have crazy power, I have the points ignition as well and yes, a electronic ignition would be better. I got a dist recurve kit (about $7) and recurved my dist and timing. You really need a timing light and set your timing, 2* off can make a big dif in the seat of your pants. You also need to set your initial timing and total timing, total being most important. Do not exceed 36* total timing (initial and mechanical, no vac), or around 32* with vortec heads
 

I have a chevy 327 putting out about 350hp and used to brake trany mounts everytime I got on it hard. Got tired of buying mounts and solid mounted the trans and havnt broke any mounts yet, the motor was solid mounted instead of using motor mounts too, I have had to take the engine brakets off and weld up cracks in them from hotroding it on the street. You do not need this kind of power in a jeep in my opinion, the engine and trans were there when I got mine so, they stayed. I have found that off road it is not real good having that power, just the slightest touch of the peddle and you are spinning tires (not good when you want traction). It is a blast though flooring it on the street, but with the short wheel base there is a lot of torque steer. You could put a cam in it and gain some power but still not have crazy power, I have the points ignition as well and yes, a electronic ignition would be better. I got a dist recurve kit (about $7) and recurved my dist and timing. You really need a timing light and set your timing, 2* off can make a big dif in the seat of your pants. You also need to set your initial timing and total timing, total being most important. Do not exceed 36* total timing (initial and mechanical, no vac), or around 32* with vortec heads

Short wheelbase and torque steer ! That would be a BIG issue with a CJ as that could be the difference between making it up (or down ) a hill safely or rolling it . Yeah . We want to turn wheels with enough power but hope NOT to spin then anymore than they will anyway as this is detrimental to the whole reason of WHY we seek more power to begin with. We want you to keep rolling , not dig a trench and wait for a tow or a Huey to air lift your jeep out. That could be expensive ! 69jeepcj made the case , too much is NOT better. Diesel torque would be GREAT but power to weight ratio dosen't fit in a CJ . Nice idea but you can only build a jeep so much before you OVERbuild it . we learned this years ago when we put an LT1 'vette SB in a '67 AMC rambler to build a home made rambler SST since we were short on 343's at the time . Once again , motor and trans mounts , throttle and kick down , drive shaft , trans lines , CLEARANCES , you name it ! a summer in hell . Fun , but hell. With a 4.11 SOA rear and a lousy front end with oversize coils , it was terror on wheels . Don't know how it didn't roll . Best advice is to seek more torque from your engine at low rpm and select right gears , transfer and trans to get you up the hill . Greg
 
I've got the 304 in mine, these were light in HP like around 135. Torque is a more respectable number, it escapes me at the moment. It feels really strong in a CJ5 because it's pretty light. I've also got the dana 300 t case which has pretty low gears which help. I really don't want for anymore power in mine. I'd say a stock 350 with headers, reasonable intake 4bbl, good ignition would make it feel like a hoss. Just remember when choosing an engine torque is the more important factor when offroad. The closer to stock it is the less problems you will have, less problems mean more time in the seat, less under the hood or being towed home.
 
I've got the 304 in mine, these were light in HP like around 135. Torque is a more respectable number, it escapes me at the moment. It feels really strong in a CJ5 because it's pretty light. I've also got the dana 300 t case which has pretty low gears which help. I really don't want for anymore power in mine. I'd say a stock 350 with headers, reasonable intake 4bbl, good ignition would make it feel like a hoss. Just remember when choosing an engine torque is the more important factor when offroad. The closer to stock it is the less problems you will have, less problems mean more time in the seat, less under the hood or being towed home.

I'll give jeep(AMC) credit when they built and installed the 304 in the CJ, it was the answer to "BIGGER IS BETTER" . The 304 may not show much on paper in terms of HP , but torque was enough to push a school bus as IHC made a similar engine and got those kids to school across the country and probably others too ! If you got a good 304 , stick with it , I would say . The 360 and definitely the 401 were not as efficient gas mileage wise. All I ever wanted to do with my 360 when I had it in a '78 cherokee w/4-speed t-18 and d44 rear was improve highway speed and economy . Couldn't decide , a cam and intake with a Holley two barrel or find a five speed to work with it. At the time , the only five speed was a little too big to go into the body and chassis so that was that . Never did go with the engine mod as I felt the t-18 would just go default mode on me and result in more gas wasted . The case is yet made again , bigger is NOT always better !
 

I think we all love horse power as much as anyone else, and I have been bitten by the hp bug currently myself and am seeking more. "BUT" in a jeep, especially a cj-5 there is danger, more danger than a car. I get torque steer (bad) when ever I floor it and when I let off of it from being floored. It is scary sometimes, so I let off around 70-80mph, torque steer above that isn't for me. So, I get a quick blast for a few seconds then let off. Off road that power can hinder you, unless you are blasting the sand dunes. If you are wanting more from your 350, I would start with a ignition upgrade and dist recurve and see if you like that, because that will give you some seat of the pants gains. Then if you want more, I would look at some cams and stay under 500 valve lift and 230 duration @.050, I currently have comp cams extreme 4x4 cam,( CS x4 254H-11) valve lift is 462, .210, 218@ .050 on 111.0 lobe separation. I love it! Just be careful and know you just made a death trap..<<<< really! control of your emotions will keep you alive and rubber side down when driving it. You will love it!!! Horse power wins at the track, torque wins on the street! and off road!
 
Thanks for all the replies, I think I get the idea. The ignition upgrade is definitely next, and as for the cams? I wish I knew more about them and engine components in general. CS x4 254H-11) valve lift is 462, .210, 218@ .050 on 111.0 lobe separation? Dude, is that even English? lmao, As for the sand dooning, its funny you mention, the last time I went out, aside from some trail blazing and small river crossing, it was all sand dooning (yep, we have some gnarly sand dooning up here in Alaska) I was screaming up some of these hills that even 4 wheelers and dirt bikes wouldn't even try, I was just killing it in the jeep! But when I would get to the top I'd be forced to navigate these tight little trails in 4 high. going slow and controlled in 4 high is a b****! I basically just have to ride the clutch as even idle speed is too fast and jerky. I wish I could just push a button and go from 4 high to 4 low. Shifting the transfer case is a bit of a chore sometimes : / Maybe a 4 speed with a granny gear is the ticket...so many ideas, not enough time or money!:roll:
 
I think we all love horse power as much as anyone else, and I have been bitten by the hp bug currently myself and am seeking more. "BUT" in a jeep, especially a cj-5 there is danger, more danger than a car. I get torque steer (bad) when ever I floor it and when I let off of it from being floored. It is scary sometimes, so I let off around 70-80mph, torque steer above that isn't for me. So, I get a quick blast for a few seconds then let off. Off road that power can hinder you, unless you are blasting the sand dunes. If you are wanting more from your 350, I would start with a ignition upgrade and dist recurve and see if you like that, because that will give you some seat of the pants gains. Then if you want more, I would look at some cams and stay under 500 valve lift and 230 duration @.050, I currently have comp cams extreme 4x4 cam,( CS x4 254H-11) valve lift is 462, .210, 218@ .050 on 111.0 lobe separation. I love it! Just be careful and know you just made a death trap..<<<< really! control of your emotions will keep you alive and rubber side down when driving it. You will love it!!! Horse power wins at the track, torque wins on the street! and off road!

111.0 lobe separation angle ? That's right up there with the LS series ! Your are one of the BAD BOYS ! I better look out for you ! I'll bet when they see you storm in' a trail , there's
clouds of dirt flyin' out from under your jeep ! We should call your jeep " THE LONE RANGER " !
 

A trany swap is what it sounds like you are after, t-18, sm420, sm465, np435 are all 4 speeds with low 1st gear. In a situation as you describe above, a low 1st 4 speed would be the answer. More power would only get you there faster and do nothing for trail at the top, but a trany swap would allow you to shift to first or second and keep going at the slower speed you want. Torque is what you are looking for not more power in my opinion. Torque allows you to use that power but at a lower speed.
 
yes. And the reason Iv been steering away from that option is because I wouldn't know what would work. Your running a chevy small block in a cj5 too right? Honestly I don't even know what transmission I have now is. Those transmissions you mentioned above, are they meant for jeeps, or chevy blocks? Will I have to make adustments? I gotta get a pic from under my jeep and show what Im working with down there. And also, you got my curiosity going with the whole cam situation. I been on Comp cams website and others reading up. there only like $125. That aint sh**! And they got a whole bunch of different 4x4 cams that all run, idle and romp at different specs, Im gonna dive into this stuff till I know all about it!
 
Brother, who gives a rats' ass what anyone says you should do... it's YOUR Jeep. While it's prudent to heed the sound advice of advid builders, it's equally nice to be unique while staying true to a common sense blend of form and function. It's the trial and error approach that teaches you the basics. Yes Axles are the foundation, But why have Dana 60's or Rockwells if you can't turn them efficiently? i won't tell you what to do or even what you should do. If you want that 350 chevy by all means go get it. But back it up with a 400 and D44's at the least. Common sense blend. This would be relatively inexpensive and give you years of enjoyment on the big trails and be reliable enough to be a daily driver.
 

the t-18 was used by jeep, international, ford, and I think dodge at some point. The SM tranies are GM truck tranys and the NP is ford. If you choose to do a trany swap I would stick with a GM trany so it will bolt right to your engine with no adapters, you probably already have an adapter for your t-case to bolt to your current trany and would think it would bolt to the newer GM trany as well. Their may be driveshaft mods required, but you already have a gm set up so maybe not (already been done). You may be able to just swap tranys and be good to go, May need new clutch also, you would have to do a search on the swap to find out exactly what needs done, and know that most of it has already been done with your current GM set up. I am not trying to tell you what to do with your jeep, just from what you described, it sounds like a trany swap would be better for your needs than an increase in power. Im all for more power!! When your looking at the cams, don't go by just the hp numbers as a lot of those cams produce that power high up in the rmp range, pay close attention to the torque curves, you want the power at a lower rpm with lots of torque, the torque is what pins you to your seat when you floor it.
 
So it seems 1986 is the cutoff date reguarding cams for chevy small blocks. '86 and lower use a flat tappet cam and '87 and up use a roller cam? My engine is a 4 bolt main out of an '86 pick-up and narrowing my search to the "extreme 4x4" cams they came up with 4. I think the "very strong torque, smooth idle" cam is the right cam for my application. Take a look... 12-231-2 - Xtreme 4 x 4? Hydraulic Flat Tappet Camshafts
 
Yes , I believe 1987 was the first year of the Gen two small block Chevy with roller cam and a one piece rear main seal . The cylinder heads were updated as well , improved valve covers for better seating to reduce oil leaks , supposedly improved valve guides , factory porting , just a better design that even the vortec design improved on by the '90's. they would be a good choice if you can get one in good shape.
 

yes, later chevy blocks used roller cams. Im not the best at picking a cam, still learning the meaning of all those numbers myself since the purchase of my cam. What I have been told is, that once you start getting over .230@.050 you start to lose idle vacuum which can give you issues with the engine idling and can have a negative affect on power brakes because they run off of vacuum (no brakes, not good). But roller cams act a little diff than flat tappets and the link you posted also says it has a smooth idle. I have seen that cam suggested to quite a few on hotrod forums to people with 350,s. I had a cam picked out for mine and called comp cams and told him I wasn't sure if it was the best one for me or not, and he asked me a few questions about my engine and picked a cam for me, he said it would produce more hp and torque than the cam I had picked out. I would suggest calling them and asking them to help you pick a cam, because the cam is the heart beat of your engine and if its not right for your motor you will NOT be happy. If you order a cam, get a new timing set. The cam and timing set go hand and hand, its not a absolute must be should be changed with the cam. Follow brake in procedures to the letter.
 
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