pvillesmith

I've got a 2002 ls1 put a 224/228 .534 .537 on a 112 lsa also 1.85 rockers dual coil lunati voodoo springs good to .660 .......problem is I flatten out on the dyno at 4K tuner says he doesn't know why I don't either any thoughts?

HCI2000SS

iTrader: (2)

Sorry, but your tuner doesn't sound to bright lol. Are you running stock injectors and fuel pump?

pvillesmith

Yes to both its actually in a 04 silverado with the stock intake/throttle body on it

A.R. Shale Targa

iTrader: (2)

Please tell me you're NOT using the stock pushrods ????

ws6fitz

He would be fine with stock push rods with a cam only setup. Yes it would be ideal to have chrome molly ones but this shouldn't be an issue here.

The question is what length push rods are you using?

A.R. Shale Targa

iTrader: (2)

I stand corrected...you are absolutely right !!!! He would be just fine to 4000
rpms !!!!!!

ws6fitz

I ran mine for 3 years. Car made over 400 to the tires and ran consistent 11's.

Know others that have done the same. So that 4000rpm crap is inaccurate as I was spinning to 6600.

A.R. Shale Targa

iTrader: (2)

Maybe you got lucky...just because people reuse TTY head bolts doesn't
make it right. Valvtrain harmonics is somewhat scientific. Did you have hollow valves ? What was your cam lift, lobe profiles, etc.? Were you running
beehives with 300ish pressure ??
I mean there are plenty of factors that can contribute to the OPs issues. His
rocker choice is usually used for a bit more lift and power for the guy who
doesn't want to change the cam. The more aggressive aftermarket cam lobe
really kicks a valvspring when that higher ratio rocker arm is used. Now that
he's approaching 580-590 lift and has valvsprings known for 380-400 open
pressure...there simply is no way I'm buying that his pushrods are not the
weak link in the equation. Plenty of drag racers have lightened their valve-
trane parts over the years, but always found that too small (diameter) or too
thin a wall thickness push rod always created deflection which acts like a mec
hanical rev limiter.

ws6fitz

Lift on my cam was more then what he was running. He said he was .53x. I was at .560. The cam he is running is relatively small and would make a great street cam. As for springs I was running Patriot Gold springs that were good to .650 lift. I also used stock rockers and this could be his concern using the ratio that he is using. I'm not at all saying it isn't a possibility that the PR's are the problem here, but I don't that that's the issue. My guess is its the large rockers and he is getting into some valve float, hence why his power is falling off the table at 4k RPM's. I don't see at that power level the stock PR's being the problem, but for the $100 it would cost to get CM pushrods that would be something I would do before I went and put different rockers on the car.

ds98formula

iTrader: (3)

Can you do it? Yes. Should you do it absolutely not.

OP can you post the Dyno sheet. Also find a new tuner if he can't at least help you narrow it down.

garygnu

too much valve spring for that cam,if you ask me .how many miles on the motor ? .you didn't need 1.85 rockers ,should have got a cam with more lift .pull the valve covers and inspect the valve train .

Holloway5

Invest in some good push rods. Also check fuel filter, if it's never been changed before

Fotis

iTrader: (2)

couple issues i see here
#1 ur tuner guy is not the best, look around on here for someone in your area, If you in GA try Vengence Racing. Mike is really good, never done me wrong.

#2 the pushrod would not be the cause of your issue here, all though it would be ideal to get some harder ones... mostly to be safe since stock has a history of bending at high RPM's with some after market cams

#3 the most likely reason for your issue is probably the injectors/ fuel pump. you can find some LS1/LS6 injectors pretty cheap on here. and you can use something called a "boost-a-pump" or since u got a truck its easy to just get a after market more power full pump.

#4 get some good plug in your car, not really the cause of the problem here for if ur looking for every last HP go buy 2004 Z06 NGK plugs.


also one last question why did u got with the 1.85 rockers and not the 1.7... what was the point of that, unless u did indeed replace the push rods with after market ones? am i missing something here?