I'm currently driving a 4th generation 3.4L powered Pontiac Firebird. I've noticed quite a few differences in the response of the motor, the powerband, and the general performance of this particular car. I figured I'd write this to inform people on the differences between the 3.4 in a 4thgen and a 3.4 in a 3rdgen. First off, The 4thgen 3.4 has less lowend grunt. I would assume this is do to ignition and intake differences. The 4TH 3.4 intake setup has shorter runners which should push the curve higher in the RPM band (it does). In comparison, the 4TH 3.4 has more power middle to high RPM than at low rpm- The 3RD 3.4 (utilizing the 2.8L intake manifold/plenum & distributor), Provides MUCH more power lower in the RPM band than the 4th 3.4. However, the 3rd 3.4 seems to run out of steam up high in the Band. The middle RPM band of the 3rd 3.4 seems to have quite a bit more power as well. I hope that was decently explained (Who knows ) As for general performance, I would say that the powerplant with 2.8L induction makes more power (According to my backside). The car I am driving has the Y87 RPO code.
Now, for the FEEL of 4th VS 3rd, The 3rd has more visibility, and to me is much more comfortable to drive (4thgen seats seem too low to the floor). The steering seems less responsive, but somehow tighter (???). The Car feels heavier (don't know if it is), It reminds me of driving my old Monte. That's pretty much it, not as comprehensive as I would prefer, but I'm a poor writer. I can answer questions, but overall, I'd say the 3.4 in a 3rdgen is a much better idea...too bad GM didn't make it sooner.

 

Thirdgen's are lighter than 4th gens, and considered to be the better handling car out of the box. This is based on the top models though.

But its no contest, 4th gens have the more comfortable ride, I believe this is said because the 4th gens have coil-over shocks, so don't need such stiff springs. Less shock is transfered to the chassis as the suspension travels, creating a more comfortable ride.

Thirdgens are lower, and usually have better aerodynamics (firebird mainly).


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Take the above info as you want, its based on information I have read on this board, and others. As well as my own experiences with 3rd and 4th gen F-bodies.

My opinion is not fact.

 

For more low end grunt & off the line, it looks like 4th gen 3.4 cars had 3.32 geears, while we have 3.42. Maybe not that much diff, but it all counts.

 

I am not a fan of the 4th gen. Only the Firebird looks good. Even then its better be a black 6 speed or forget it. I think they started losing touch with the design in 91-92 with them funky noses. Though the Firebird some how got turned around. 4th gen aro is fugly.

 

I dont mean to sound dumb, but when did the 3rd gen have a 3.4 in it? I have a 1992 which is obviously the last year of the 3rd gens and it has a 3.1

 

We've been swapping them in.

 

"I'd say the 3.4 in a 3rdgen is a much better idea...too bad GM didn't make it sooner."

sonner as in in the 3rd gen instead of waitin till the 4th. 91-92 could of had it.