IntegraVTEC

iTrader: (4)

Currently I have a 98 TA with a 110K mile stock bottom end with a new oil pump, 232/234 .595/.598 112+3 LSA Comp Cam, Ported LS6 heads that have been milled .012" and using .041" head gaskets. I don't have PTV clearance issues due to the valve job on the heads and a medium sized cam. I have a crappy stock LS1 intake on it still but do have pacesetter lt's and ory running into the stock exhaust piping back to a magnaflow muffler and out the back with some nice tips. The car is a 6spd and is tuned as good as can be with what it has. My question is, how much power will a fast 90 or LS6 intake pick me up on this setup considering I have ported heads and a hefty cam already. Is the LS1 intake choking me up alot? Also with this setup should I be maxxing out my stock 28.6 lber's? My Injector Duty Cycle is in the 128% range and is leaning out in the higher RPM's. I didnt think I should be maxxing out the injectors and I think it could be the fuel pump crapping out on me since it is stock, but that will be addressed. Just tell me your guy's thoughts on this setup.

InchUp

iTrader: (2)

As an obvious observation, you'd do well to read up on injectors.

http://www.injector.com/faq.php

IntegraVTEC

iTrader: (4)

I'm aware of how injectors work, the 128% duty cycle is what is happening during the datalog's. The Injectors are going static because they physically can't provide anymore fuel. But the duty cycle will naturally go up if the fuel pressure is falling. The main reason I am blaming this on the fuel pump is because of the VE table. It looks linear up to 4400 rpm's and then jumps almost straight up 10-15% within 400rpm's. With my head/cam setup this should not occur and leads me to believe that the fuel pump has reached it's max at that point and starts to drop fuel pressure in which case the injectors must open much longer to supply the right amount of fuel at a lower fuel pressure. Another indication to me is some funny humming going on in the trunk area!!!

FlashLCD33

iTrader: (8)

I believe stock injectors should be alright for your setup, but it wouldn't be a bad idea to replace them in the near future.

Hook up a fuel pressure guage, see what kind of reading you're getting.

And yes, with a h/c car a stock ls1 intake is limiting. You should see nice gains going with a LS6, and even nicer gains with a FAST.

jstero99

iTrader: (1)

I agree with the intake upgrade not sure how much more power you will gain but the LS6 intake will definitly improve your setup. I also would put a fuel pressure gauge on and see what it is doing. You will see a dramatic increase with fuel demand when the power enrichment table takes over when you hit a certain rpm but it usually takes over before 4400 rpm but that can be changed during tuning for whatever rpm you want it to so if its not your fuel pump thats something you can look into but you might be on the right track with the pump because I have similar set up and my stock injectors are nowhere close to 100%.

IntegraVTEC

iTrader: (4)

I am going to get a fuel pressure gauge and see what it's doing. I have a set of Flex fuel injectors out of a 05 avalanche which are rated according to the HPTuners file they came out of 35.7 lb/hr injectors which are right at 7 lb/hr more than the stock 28.6's. As for the fuel in the tune goes I am running open loop with no o2's for right now so the afr is being commanded from the open loop f/a table which I have set to command 12.96:1 afr above 75kpa and power enrich is set to come in at 2500rpm above 75kpa as well but commands a 12.8:1 afr for a little safer afr for the compression hike I got with the heads and thinner head gasket. I also forgot to mension that I am running the car using the 98 2bar SD enhancement but I am using a 1bar sensor that has been recalibrated in the engine diag. tab to see the 1bar. It ends up working just like a 1bar SD enhancement. I'll check the fuel pressure and get back with you guy's on it, if it holds good fuel pressure the whole time then I will be swapping these flex fuel injectors in the car with the jumper harnesses to see if they help any.