Firebird with GNX setup?

[Spoolin Hooligan]

Now granted i got this info trolling a Mustang forum that came up when i googled something else. But someone on there said that Pontiac made a firebird with the "GNX" engine. Now pardon my ignorance if this is true. I really dont know anything much about TTA's except they share the same drivetrain as the GN.

 

[jarredsoon]

I think the intercooler on the TTA is the same as the GNX. I know the TTA has a cross drilled crank and different heads & exhaust manifolds compared to the GN.

 

[pacecarta]

the 87 gn (turbo regal) and gnx motor only differed by the turbo, the intercooler fin count and the chip
that said the tta and the gnx are far from being the same
the two engines though they share some of the same parts like block (109), timing cover intake plenum fuel rail and injectors ... other than that they arent even close

PAS was responsible for building the TTA motor for pontiac and although its based off a buick 3,8 intercooled motor its unique enough that its a pontiac motor as they paid for the research and build as well as the packaging into the fbody

the tta had different heads (from fwd car ) , different valvecovers, rocker arms and headers due to heads ,
the tta block though it was a 109 block it differed from the GN-GNx 109 as the tta was also cast with SG1 on the side
the TTA internals had a crossdrilled crank ..the gn-gnx did not get that crank
the tta pistons were different from the gn-gnx to fix the compression because the fwd head cc was different than the gnx 8445 head

the tta had a totally different oil cooler from the regal .. the regal routed oil through the brass radiator oil cooler , the tta had a std f body radiator that only had trans oil cooler so they routed coolant from the radiator to the oil adapter , the TTA oil cooler also relocated the oil filter to fit the chassis and had an oil pressure gauge mounted on a special oil cooler adapter nut that held the cooler adapter to the oil pump
the tta intercooler had the same fin count as the gnx but used a differnt intercooler shroud
the tta received the same turbo as the Gn and other turbo regals

 

[tta983]

As far as the boost goes, the TTA had 16.5 lbs of boost stock. The orifice in the "y" at the wastegate hose was .040 and the one in the turbo regal was .050, the oil filter is also different from the GN or GNX.

 

[JP112_89]

Thanks Paul! Another thread saved...

Joe

 

[notacarlo]

The suspension on a GNX was vastly different.

 

[pacecarta]

The suspension on a GNX was vastly different.

i have to disagree

the suspension on the gnx was different than the gn but the gnx and tta (all f body 82-04) was very similar ,

both are solid axle torque arm setup

they differ in packaging due to the rear axle and difference between the f-body and the g-body.

no upper control arms so it used torque arm to prevent axle rotation. the tta rear had provisions for a torque arm to bolt to the center section. the gnx had to add a rear cover to attach a torque arm.
the tta anchored the torque arm at the trans crossmember . the gnx added a cross member.
coil springs mounted on perches on the axle tubes.
mono tube shocks.
lower trailer arms (they are actually the same parts )
panhard bar to keep axle centered.


on a note the tta did not get an 8.5 rear center section or the 3.42 gearing of the regal ,
TTA had 3.27 9bolt which was a different rear than the std fbody 10bolt 7.5"

 

[Jan Larsson]

the 87 gn (turbo regal) and gnx motor only differed by the turbo, the intercooler fin count and the chip
that said the tta and the gnx are far from being the same
the two engines though they share some of the same parts like block (109), timing cover intake plenum fuel rail and injectors ... other than that they arent even close

PAS was responsible for building the TTA motor for pontiac and although its based off a buick 3,8 intercooled motor its unique enough that its a pontiac motor as they paid for the research and build as well as the packaging into the fbody

the tta had different heads (from fwd car ) , different valvecovers, rocker arms and headers due to heads ,
the tta block though it was a 109 block it differed from the GN-GNx 109 as the tta was also cast with SG1 on the side
the TTA internals had a crossdrilled crank ..the gn-gnx did not get that crank
the tta pistons were different from the gn-gnx to fix the compression because the fwd head cc was different than the gnx 8445 head

the tta had a totally different oil cooler from the regal .. the regal routed oil through the brass radiator oil cooler , the tta had a std f body radiator that only had trans oil cooler so they routed coolant from the radiator to the oil adapter , the TTA oil cooler also relocated the oil filter to fit the chassis and had an oil pressure gauge mounted on a special oil cooler adapter nut that held the cooler adapter to the oil pump
the tta intercooler had the same fin count as the gnx but used a differnt intercooler shroud
the tta received the same turbo as the Gn and other turbo regals

Spoke to Bill Owen about the SG1 blocks and he told me that is just the designation that they were cast at the Saginaw foundary line 1 so no difference from any of the other 109 blocks.

Also with regards to the cross drilled crank, Bill were involved in the returns and quality claims and the crossdrilling was simply an update done that brought down the warranty claims drastically.

Buick (well BOC really) built the TTA engines to the PAS specs but was originally put together and developed by Buick/Pontiac and Bill Owen was instrumental in that whole project.

 

[charlief1]

How much smaller was the combustion chamber on the TTA versus the GN?

 

[BEATAV8]

good thread

 

[2QUICK2B6]

chassis: front MacPherson strut
rear live axle, 3.27:1 Borg-Warner "Australian"
limited slip with torque arm
sway bars 36mm front, 24mm rear