CalSpeedPerformance

iTrader: (64)

Hmmm im a ls1 guy that has done about 50 heads/cam setups on ls1 cars, tuned a few hundred cars and dealt with about every problem ive read about but I cant seem to find the missing horsepower in this setup


It dynos 342 rwhp locked converter with the following:

PRC 5.3 Stg 2.5 heads milled to 59cc
234/238 @ 111 custom camshaft
fast 92/92
stock 10 bolt with 4.11
locked converter 4l60e
7.4 pushrods
prc double gold valvesprings
obx longtubes with true duals

timing at 28 degrees no knock retard, 13.0-13.2 a/f everywhere.

The car runs well but back to back on the dyno puts down 80 less rwhp than another car with the similar setup with a smaller cam on same dyno, same day.


Any ideas? I figure ill run a compression check on the 80k mile motor first....but after that I cant find a thing wrong with it.

Jditlfm

iTrader: (26)

I would do a leak down instead of a compression test. Did you log the trans slip counts during a run to make sure the TCC was not slipping under a WOT Pull? The TCC could just be junk.

CalSpeedPerformance

iTrader: (64)

Tranny isnt slipping at all...even calculated the rpm vs mph on the dyno to make sure.

I'll leak it down at same time as compression test.

hellbents10

iTrader: (10)

I have had vehicles with trans issues rob power. Like stated above it could be the TCC or it could be inside the trans.

CalSpeedPerformance

iTrader: (64)

Im pretty sure the tranny is fine..ive sprayed on it with 150 on top this weekend and it worked like a champ. Its a fresh race built tranny and edge 4000 stall converter that ive had no issues with

sedanman

iTrader: (10)

I would do a comp. and leak down test.

john563

iTrader: (17)

I hope you figure it out...I have those same heads and ported fast 90/90 and my cam is almost exact 232/238 6xx 6xx 111lsa+2 and a A4 too,and put down 435rwhp 407rwt..Hopefully this gives you an idea where you should be..Good luck I hope you fin d the problem

bad95killer

peace

sschkade

iTrader: (7)

Which injectors are you running, and @ what % duty cycle are they?

Magnet

iTrader: (36)

sounds stupid, but are you sure the TB is opening all the way or there isn't something in the way of pushing the pedal all the way down?

CalSpeedPerformance

iTrader: (64)

42lb green tops, They consistantly run up to 56% duty cycle at the top of 3rd on dyno and 1/4 mile pulls. Also the MAF lb/min max is 45.5 at 6500rpm, MAP kpa 100.

CalSpeedPerformance

iTrader: (64)

We thought the same thing and checked full throttle, 100%. Ive also changed plugs/wires/fuel filter etc since with no change.

ls1toy

i recommend a leak down test