89 TTA Knocks when it shouldnt!

[pwrhws]

Its been a long time since I posted here. Been away from the Buicks for a while now.

I have a customer that has a 89 TTA (TA49, ported heads, 206 cam, 42#inj), we recently went through the car and tidied a few things up and to touch up boost and fuel pressure adjustments also recently installed a turbo tweak chip as well.

This car knocks hard (audibly) at the hit of the throttle and after every shift (did with the reds chip that was previously installed), running 16# of boost and dialed back the timing to 15.5 degrees. AFR's are in the mid 10's..still knocks like crazy.

Does anyone have any good ideas? Ive covered all the basics, this one has me beating my head against the wall.

 

[RmvBfrFlght]

Could the owner have possibly put low octane fuel in the tank? Or possibly it is old fuel.

Maybe the shutter wheel on the damper slipped and the timing is off. Short A&B on the ALDL connector and the timing should be at 15* BTDC. There is a mark on the timing tab at that advance.

RemoveBeforeFlight

 

[dynoman]

This car knocks hard (audibly) at the hit of the throttle and after every shift (did with the reds chip that was previously installed), running 16# of boost and dialed back the timing to 15.5 degrees. AFR's are in the mid 10's..still knocks like crazy.

I would check The torque converter bolts & motor mounts . Sam

 

[pwrhws]

I will check the timing and see what I get.

I can assure that the knock is not false, its definitely pinging.

 

[pwrhws]

I will check the timing and see what I get.

I can assure that the knock is not false, its definitely pinging.

Could the owner have possibly put low octane fuel in the tank? Or possibly it is old fuel.

Maybe the shutter wheel on the damper slipped and the timing is off. Short A&B on the ALDL connector and the timing should be at 15* BTDC. There is a mark on the timing tab at that advance.

RemoveBeforeFlight

The car has a TA "balancer' on it. Im going to call them to varify the marks on it (there is more than 1). It seems as though im getting 31* (which seems like to be more than the car is actually getting). Im going to pull the #1 plug and see how close the mark is to zero.