Need help tuning a 408 with hpt
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From: Clermont, FL
Need help tuning a 408 with hpt http://www.hptuners.com/forum/showth...2276#post52276
just looking for a second & third set of eyes in case im missing something.
Thanks
Bill
just looking for a second & third set of eyes in case im missing something.
Thanks
Bill
If hes running stock springs with that cam, hes got big problems. The stock springs are good up to like 525 lift, not 600+. I would use double springs with that much duration and lift. Got a dyno graph?
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From: Clermont, FL
sorry, im not a big believe in dyno's 
you can feel & see(via the scan) something is up. And yes, im fully aware that if he's running on the stock springs he's gonna have issues...this would be the second person to have come to me with a large cam with stock springs. Last one was a TRak cam...640 lift on the intake...hmmm yeah i think springs might be in order 
thats the price I pay for not building their combo for them I guess.
you can feel & see(via the scan) something is up. And yes, im fully aware that if he's running on the stock springs he's gonna have issues...this would be the second person to have come to me with a large cam with stock springs. Last one was a TRak cam...640 lift on the intake...hmmm yeah i think springs might be in order thats the price I pay for not building their combo for them I guess. A dyno will show what the problem looks like from a HP stand point. You cant tell if something mechanical is wrong with some sensor scans. You dont have a sensor to tell you the valves are floating 
My scans and tuning looks good, but this was an old dyno I had...
My scans and tuning looks good, but this was an old dyno I had...
Thread Starter
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From: Clermont, FL
looks like its valve float...owner just came to pick up the car & we discussed things further & he's pretty sure its just the stock springs since he only bought a built shortblock so he just used his stock 98 heads.
