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building a 318 5.2L _ more compression

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Old 01-16-2010, 08:42 PM
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Default building a 318 5.2L _ more compression

ok i got my 96 limited with 5.2L for a street fighter (fun cruiser and friday night drag strip). I want a ride that is a sleeper and still proform daily tasks //// NO OFFROAD \\\\\ . I going to pull my drivetrain and getting it rebuilt. does anyone know what would be a good compression ratio. i dont care if i have to run 93 octane

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Horsepower 220 @ 4400 Torque (lb-ft) 300 @ 3200

Its around 18 pounds per horse power

I am getting headers from Doug Thorley headers


K&N cold air system and magna-flow exhaust

My local speed shop is going to help blue print and port and polish the engine. also there transmission will be rebuilt stronger 4 the power.

They just want me to find out what to run as compression. the one guy thinks 11.5 to 1 would give me more power
Old 01-16-2010, 09:18 PM
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idont know much on numbers but my k& n didnt help much at all with power. i borrowed a stock intake (because i got mine with the k&n) and tried it both ways..
Old 01-16-2010, 10:14 PM
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If you want a fun cruiser and daily task performer, the lower the compression ratio the better. 11.5 isn't bad. Most 350 chevys run 10. something I believe.
Old 01-16-2010, 10:22 PM
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My advice for a sleeper is to get a ECV. It looks like a typical exhaust flange, but has a butterfly valve to control the db level. I plan on doing it to mine. Straight pipe system, and a glasspack (significantly lower db at lower rpm's with little or no power loss, but plenty loud on the high end) Adjust the valve for quiet operation around town and in the staging lane, then when you go to launch BAM! open header roar. My buddy did it to his bronco, had a ricer pull up next to him acting like he was hot ****, flipped it open at the light and destroyed his little honda. The look on the guys face when he got smoked by a 92 bronco with 35" mud terrains was priceless. I believe APEXI is the company that makes them.
Old 01-16-2010, 10:38 PM
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I think you have more than intake, exhaust and headers to worry about. With that compression what cam will you be running along with injector size. Plus the computer will need to be dealt with.
Old 01-16-2010, 10:45 PM
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Or he could go carburated. Take the computer totally outta the question, and just adjust his jet size.
Old 01-17-2010, 12:05 AM
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I wouldn't go over 10 for a daily cruiser. I have a Chevy 350 that won't run on pump gas over half throttle anymore. You just can't run the compression you used to.
Old 01-17-2010, 11:26 AM
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drop a 5.9 in there.

some grands came stock with them. they're the ones with the factory vents in the hoods.
Old 01-17-2010, 12:55 PM
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Sorry stock is 9 to 1 i called an mopar guy and he said i could do 10 to 1 with out any problems. He said i should do a 6.4 stroker from the 5.2L


the speed shop has everything they need to make it work. there looking in to the stoker kit and everything i need to make it run
Old 01-17-2010, 01:01 PM
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Originally Posted by caged
drop a 5.9 in there.

some grands came stock with them. they're the ones with the factory vents in the hoods.
The 5.9 is rather over rated and under performing. You can build a better 318 for less..
Old 01-17-2010, 01:02 PM
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Are you keeping All Wheel drive? or are you converting it to 2wd?
Old 01-17-2010, 08:09 PM
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Originally Posted by nick_n_ii
Are you keeping All Wheel drive? or are you converting it to 2wd?
Yes the 318 is better i think. the 44RE will be rebuilt better and stronger. the transfercase is going to be rebuilt also

i am keeping it all wheel drive.

Last edited by gobbs_stopper; 01-17-2010 at 08:44 PM.
Old 01-18-2010, 09:54 PM
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Forge the bottom end and boost it. Take the compression down to 8.5 to 1. Then you can run 15psi on pump gas and get an easy 600 hp. You will have the best of both worlds, reliability for the street and good power. You can put c16 in it and run 25-30 psi and get insane power. You would need to have two different tunes for the ECU though. I am not sure what kind of power the block will hold.
Old 01-21-2010, 04:53 PM
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well the wife said i can only put a rebuilt stock engine. she said the headers and exhaust is ok but no crazy engine work. she wants me to keep it sane

i agree to a point i dont need 2 race cars

but i am still going to have fun with it
Old 01-26-2010, 11:03 PM
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The ZJ is gone

Well i gave my long time friends 18 year old girl my jeep. It was a needed thing to do. its only a car i will get another soon


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