High boost w/ alky opening valves?

[Roc87]

There's a couple of us here in Alb. that have installed our SMC kit and on both cars at high boost it seems like the valves are floating. I don't know how many miles is on his, but mine has 133,xxx and valve covers have never been off. When the car is cold (water temp up though) it runs high boost fine (24 - 25 psi) but once the car is fully warmed up (Running for 1/2 an hour or more) it seems like valve float at anything over 21 -22 psi, once the boost does get over it falls back down(Like the car is "falling on it's face"). Badboy86gn2's car is doing the same thing. We aren't experiencing detonation either. I'm using NGK UR5 plugs gapped at .032 and they have less than 200 miles on them, using denatured alky w/ WD-40 squirt of 5 seconds, low timing chip (19Degrees). Mine has new boost lines, and the actuator and the solenoid are fine.

I'm thinking that since the car has that many miles it might have EXTREMELY weak valve springs and the high boost is seeping past the valves. Anyone have any ideas? Am I on the right track? Thanks for the help!

 

[1badTTA]

Sounds believable to me, I had to replace my springs at 37,xxx miles due to a different cam (very mild) and lifters and the biggest culprit being a high volume oil pump plate. The valves would start to float at about 4500 rpm and car wouldnt even shift into second without letting off since it couldnt hit 5300 to save its life. I dont think it is the 133,xxx miles but the 15 or so years that have weakened the springs and now you have added more power and boost and it revs quicker than the springs could handle. HTH

 

[DonnieShort]

Definitly valve springs. Change them out and it will seem like a different car.


Donnie