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Discussion Starter #1
I'm making a little over 375 rwhp on pump gas after upgrading the intake, headers, exhaust, cam, porting the heads and dyno tuning the car. I've heard that going to a higher flow Mass Air meter, bigger Throttle Body and aftermarket Manifold yield very little return on N/A cars in comparison to the total expense, which is close to fifteen hundred for the parts. I've heard that you may see a gain of 5-10 rwhp in the higher rpm range. Aside from a power adder, where else do you/ can you go?
 

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More aggressive cam, free-er flowing heads (Airflow Research), underdrive pulley (ASP, MTI, SLP), different temp thermostat (Hypertech). Not sure if you changed the cats with the exhaust upgrade, but these can be exchanged for more free flowing ones (Spintech and Dynomax).

Composite Intake Manifold (FAST LSX)...seems to yield different results on different cars...anywhere from 2-28 rwhp...yes a big difference. Consensus says that the more bolt-ons and airflow upgrades, the better it works...which is logical because there will be less bottlenecks. Expensive for the gains though (unless you're on the higher end of that spectrum.
 

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If you have a local race engine machine shop you can talk to them about what they would suggest to do with the LS1 to supply the rwhp that you want to obtain. You could bump it up to 450rwhp with a few thousand more or if you have an extra $20,000 you can end up with a 1,000rwhp with a roots huffer...but I would suggest you install a good scatter shield and roll cage just in case. Hahaha
 

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Discussion Starter #5
Thanks guys. Not sure I want to go with bigger heads or a crazzier cam considering that I just shelled out for both the cam and heads I have now about a week ago. I wanted the car to be a daily driver that would pass emissions. I do have hi-flos with the 3" exhaust, but I have an exhaust cut out system that lets me go open header at the touch of a switch. The three things I was pondering were the Fast LX with a bigger throttle body and a bigger Mass Air Unit, but I just don't know if those things ($1500) are going to produce vs. the cost. From what I've read, the fuel system and drivetrain don't like much more than 400 rwhp if you're going to drag the car, so I've ruled out a power adder for now. If I were to go with the manifold, I'd probably go with all 3 intake upgrades, but I'm just not sold on the validity of the gains. I've heard that gains can be very dissapointing, but I'm sure the right setup would benifit, just not sure if my setup would and it's a sizeable chunk of change after the mods I just shelled out for.
 

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Have you run the 1/4 mile yet? Do you think you could beat an 03-04 Cobra with those mods? Yea I have heard an underdrive pulley helps and they arnt that expensive.
 

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Discussion Starter #7 (Edited)
According to the shop that built the car, the setup I have is good for 12.70s on a full bodied Goat, depending on traction. On another board there is a guy who ran 12.72 with 390 rwhp, which is similar to my 375 rwhp when you consider the type of dynos we used, Mustang vs. Dynojet. Dynojets generally yield higher #s, or you could say Mustang dynos are more conservative, however you wanna look at it. In any case, 390 all motor rwhp on a Dynojet equates to a 12.70 car. Add Drs or slicks and the number stars dropping. Compare that to the Cobra 1320 ET numbers to answer your question.
 

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Discussion Starter #9
My specs are in my personal profile, just click on my name. The 224 lift intake and 224 lift exhaust Comp Cams Cam and Cam Kit I have will pass the emissions sniffer test...supposedly.
 
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