BigMoneyP

My friends car had a melted piston @13psi and now swapped out the longblock and placed a 10psi spring in there now. The p28 ECU tuned with Crome was tuned at 13psi. We checked for leaks and couldn't find any. We're using the GE vaccum manifold with the wastegate vacuum coming from one of the vacuum holes. With the 10psi spring we are only getting 8psi (constant) with some blue smoke during boost. Do we need to tune this on the dyno again to reach full boost of 10psi or is there something wrong with the car and not the what the ECU is reading? We called his tuner and he told us we just need a new tune and we should prob see 10psi... which didn't seem right, so any help is appreciated.

BigMoneyP

We weren't sure of the timing that was used for tuning, my friend believes it was at *13, so we set it there with the timing light.. Idle is around 600-700 and car feels very slugish before boost. Could the timing be the problem why it isn't reaching full boost? Thx

Soccerking3000

yea make sure the timing is dead on you might be off a tooth or something...

ccivic

Hmm.. if this is a competent tuner, he should have made sure timing was set @ 16degrees. This is what all Honda maps are based off of. If you can't verify what the timing was when the car was tuned, don't beat it until you have a laptop and a wideband hooked up to it to verify that the car is running right and to make changes where needed-- it should be pretty easy to tell then.

BigMoneyP

Car was boosted at 13psi with a 3 bar map sensor. It was so long ago that the tuner doesn't really remember what mine was tuned at but my friend recalls 13 on the dyno. Good point though, we'll prob just take the car to the dyno this week.