Few questions on 402
Few questions on 402 So I have an SLP ZL402 motor in my gto. I just picked up the car and I have no clue what is even in the thing. Its got AFR heads and seems to idle nearly stock. Anyone know what these motors were supposed to put out from the factory? It looks like a stock intake manifold as well. What cams are out for a motor this sized to be a bit more aggressive without sacrificing too much mileage/drivability.
Its got LT's into Loudmouth exhaust. And a built A4. I was not asking about the rwhp but more of what slp claims this motor makes at the flywheel. Its going to a dyno eventually. But how bad is the stock ls1 intake manifold for this application?
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weird..
But just because it idles like stock does not necessarily mean its not gonna make decent power...
on a small/mild cam 402 you will probably make AT MINIMUM, 450+rwhp with those heads w/ No problem at all..
TECH Resident
Joined: Apr 2003
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From: here, ny
never heard of SLP using AFR heads... u said u just picked the car up, from who? SLP? if so, then ask them... if not, then ask who u got it from, for the paperwork of what was done... if they don't have any paperwork, then don't even believe it has a 402... the cam that SLP used was a 224/228, .591/.600, 113lsa...
How did it idle? The car pulls pretty strong but does not seem to pulll that much more than a stock ls2 gto. I dont know if it needs some tuning, more cam, intake manifold, or what.
Somethings fishy here. If its an ls2 based setup, its the drive by wire throttle body, which won't fit the smaller ls6 manifold style cable TB (78mm).
Also, if its a 402 cubic inch motor and not just some SLP "402hp package" with those heads it ought to pull pretty hard, even with a wussy cam.
Also, if its a 402 cubic inch motor and not just some SLP "402hp package" with those heads it ought to pull pretty hard, even with a wussy cam.
Somethings fishy here. If its an ls2 based setup, its the drive by wire throttle body, which won't fit the smaller ls6 manifold style cable TB (78mm).
Also, if its a 402 cubic inch motor and not just some SLP "402hp package" with those heads it ought to pull pretty hard, even with a wussy cam.
Also, if its a 402 cubic inch motor and not just some SLP "402hp package" with those heads it ought to pull pretty hard, even with a wussy cam.
TECH Resident
Joined: Apr 2003
Posts: 859
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From: here, ny
ok, 1st, your car is a 2004?... is the block iron or aluminum? SLP used iron (LQ4)blocks on the early 402s then switched to LS2 aluminum blocks on the later models... they used the 225cc AFR heads then switched to L92 when they came out... the standard cam in the 402 was a big 250/246, then also a 236/236... they came out with a 224/228 later and also a 216/229 for the L92 head engines...
SLP
go there and click on engine packages and see how many choices/variations there are...
SLP
go there and click on engine packages and see how many choices/variations there are...
My car is an 04, Aluminum block, AFR 1630 head's (225cc, big bore, 72cc chamber). I have been on their site and the only thing that doesnt make sense is the lack of power and stock like idle.
That engine should pull hard depending on the cam. My LS2 402 (massaged AFR 205 heads) makes about 570hp and 535tq on the engine dyno.. think the cam is 236/240 on a 112 LSA
A good dyno sesion will tell you if something is wrong in regards to output.
