No power under boost

[hbsky]

I bought at TTA recently and the car seems to have no power transmitted to the wheels under boost. After building up around 2-3 Lbs of boost the car vibrates and increases as boost increases. I have tuned the car to no avail, also checked tranny mount/bolts and torque convertor bolts. I also strapped the engine down in case of a bad motor mount. During normal driving at any speeds, there is no vibration, only under load/boost. The car has no KR at 15 lbs, only under shifts. I put the car on jacks with foot/e brake on and there is no vibration. Any ideas?

TIA

James

 

[BoostKillsStres]

You might want to go thru all grounds on the car and make sure they've cleaned and retightened and see if you can find someone in your area with one of the ignition testers to make sure your not missing under load. What do the plugs look like? What gap are you running?

 

[hbsky]

You were right Mark. I never think to check the obvious first, but I had a bad plug on cyl 4. I never thought a misfire could cause that much vibration. Amazing.

Thanks.