How to tell if your engine is GN or TTA?

[TurBo BiRd]

I have a Buick turbo engine in my GTA and am changing the lifters...Now I was wondering how to distinguish between the GN and TTA engines. I know the heads are different (FWD heads on TTA), but is there anything on the heads that would tell me if they were from a TTA b/c I need to know the correct torque spec for the rocker arms? (44 ft/lbs for TTA, 25 ft/lbs for GN)

Thanks, Bobby.

 

[Roc87]

TTA heads have centerbolt valvecovers, and use individually mounted rocker arms, the GN heads use rocker arm shafts and don't have centerbolt valvecovers.

 

[TurBo BiRd]

Then I have a TTA engine.

Thanks alot, Bobby.

 

[Quick6'n'-K.C.]

Q?? what is wrong with the lifters in the car now???

NAPA sells good lifters for our cars

BRYAN

 

[TurBo BiRd]

I got the engine rebuilt b/c I spun a main bearing and when it got rebuilt, the lifters didnt get changed so they finally collapsed. i got a set of hi revs from posotn, car should be running tomorrow.