383 ls1
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Launching!
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383 ls1 So I need some help on how to build my 383 LS1. The goals for the engine is to make 500hp and operate in the 2000-7000rpm range. I will be using 241 heads, 10:1 compression, 1 3/4" to 1 7/8" stepped headers. Engine will be using a carburetor and will be pushing a 3000 pound car. The car will have an automatic transmission with overdrive and a 2500 stall. A 4.10-4.30 rear gear. Can anyone recommend a cam with a rough idle and an intake manifold to use for the carburetor? I'm not used to carbureted 383 LS1's.
Thanks!
Thanks!
Thread Starter
Launching!
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it would be nice to get 500rwhp but not being picky 500hp is a lot of power regardless. the engine is going in my 1970 trans am and want to keep it simple since I have no smog. I also want to keep the shaker hood (my favorite part of the trans am). I already have the long block but dont have the PCM, fuel pump, injectors, harness, etc. so i figured carbureted would be cheaper and easier. Bore size would be 3.935? Isn't a 383 LS1 stock bore with a 4" stoke?
Thread Starter
Launching!
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your car made 480-490rwhp? my alternative was to sell the ls1 long block, get a LQ9 408 with L92 heads but im just shooting for low 11's in this street car. would a ms3 work well to the 7000rpm or would the extra 37 cubes affect the stated 2300-6800 rpm range?
Last edited by Fast 95 Z28; Apr 22, 2011 at 06:42 PM.
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Powerwise you will be handicapping the engine with (relatively) crappy 241 heads and a (relatively) low 10.1 compression ratio. The extra cubes probably won't add a whole lot of top end horsepower, although the torque curve should look better.
TECH Senior Member
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are you going to use the edelbrock intake ignition kit?241 aren't really bad ,but try to find some 243s.get a custom cam from Patrick-G .I have never seen a 500hp sbc with a dual plane intake.I have one on my 427 sbc.
Thread Starter
Launching!
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i'm going for the 10.1 compression to run 91 octane and not race gas. compressions more crucial when you don't have knock sensors. do you guys think the engine should make 500fwhp?
Thread Starter
Launching!
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A factory stock LS2 is at 10.9 and will run on 91. Any tuner should be able to work around detonation. I would stay closer to 11:1 and at least run 243s or get the 241s ported. IMO a 383 with a set of PRC LS6 heads and an MS3 cam on a 112LSA would make a killer street engine. Would probably hit your goals.
What do you have already?
What do you have already?
Thread Starter
Launching!
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i have the long block and 241 heads. the long block i bought was from a 98 z28 with 100k miles. it came with a new alternator, water pump, and coils for $1000. im not sure if the engine has an LS6 cam in it already since the guy had yellow springs on the heads (LS6 springs if im correct). i found the 241 heads from a 2004 gto with only 17,000 miles on them for $150. I need to buy the rotating assembly.
TECH Enthusiast
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IMO, I would get a set of l92's which are relatively cheap. But the matching edelbrock intake, use the MSD ignition system.. You can make 500 pretty easy, with lower compression though you will need to have a fairly aggressive cam. I would lean towards the 11:1 side on compression, still pump gas friendly but will make a bit more power.
l92 heads will not fit ls1 5.7L bore!! with my experience you cant go cheap on the heads if you want good results
241 heads will be good for 380-400hp 243 will be in the 400-420 stock heads unported some people will dyno a little more and some a little less 6 speed trans will dyno more then auto also why are you going cab you can get a harness and computer for about 350 fuel injection is the way to go!!
241 heads will be good for 380-400hp 243 will be in the 400-420 stock heads unported some people will dyno a little more and some a little less 6 speed trans will dyno more then auto also why are you going cab you can get a harness and computer for about 350 fuel injection is the way to go!! Last edited by 09camaro383; Apr 23, 2011 at 06:36 PM.