Are all 3100 manifolds the same?

[phat_ridegt]

^^^^^^^^^^ i konw they use dthe 3100 from 95-present right? i have a 98, will all the years bolt up? i have a chance to get one for dirt cheap...very good for porting...im pretty sure they all work but just wanna be sure...thanks guys

[bszopi]

94-99 will all be the same. The 3100 switched over to the 3400 design in 2000, so anything 00+ will be a different design.

Not 100% sure on this, but the EGR might have changed somewhere in there (96-97?) so that might also be a slight difference between some of the years.

[Manitcor]

EGR on 3100 manifolds changed 2 times, once in 96 it was still a vertical mount but the mount was for a different EGR style (an adapter can easily be made if you have a 95 or earlier EGR).

The 2nd time was in 00+ where it went to a side mount type which as far as I know cannot be adapted to the older EGRs.

for the lower intake manifold and the heads you can use any year but for the upper intake you should get a 99 or older.

[phat_ridegt]

i have a 98....so if it's a 95 manifold, will i be able to use my egr or will i have to adapt it?

[geoffinbc]

EGR on 3100 manifolds changed 2 times, once in 96 it was still a vertical mount but the mount was for a different EGR style (an adapter can easily be made if you have a 95 or earlier EGR).

The 2nd time was in 00+ where it went to a side mount type which as far as I know cannot be adapted to the older EGRs.

for the lower intake manifold and the heads you can use any year but for the upper intake you should get a 99 or older.

Actually you can mod the EGR to work. I have made an adapter plate to fit a 1990 EGR system to a 2000+ intake. I will post pics when im done. It is made out of billet aluminum stock.

[95BlackRoseZ26]

So you're saying you adapter the obd1 egr to the vertical mount 2000+ manifold? If so, I'd love to see some pics, as I'm wanting to do the same thing right now for my 3400 swap.