3400 headers on a 3100

[fire beast]

I have heard of some problems clearing the firewall on a Grand am when you try to swap 3400 headers onto the 3100 engine in the pre 99 style. can someone confirm this or not? because headers would be nice to upgrade......

[bszopi]

I can confirm that they will not clear the firewall in L-bodies or J-bodies, but as far as N-bodies go, I can't tell you. One of the quickest ways to tell if its an absolute no go would be to look at the routing of the stock downpipe. If it goes under the steering rack, they won't fit. If it goes over the steering rack, there is a good chance that they will fit, but not 100% until you try it. Take a look at your stock setup and go from there (feel free to post what you find out here).

[Canada]

As similar as the 95-98 GA's are to the Beretta chasis.....I am more than willing to bet they won't fit.

[vsop4me3.1]

how much bigger are headers compared to the stock exhaust manifold? I got about 4 inches from the heat shield to the firewall

[bszopi]

Well, here is my world famous (ok, maybe not the whole world...) picture comparing the stock Beretta rear manifold profile with the S&S headers profile. Yeah, there really is that much of a difference!!

[vsop4me3.1]

prior to putting headers on what would I need to upgrade? would I need an additional fan?

[v6h.o.]

hehe that pic IS world famous!

[ikessky]

I know a guy who tried them on a '94-'95 Achieva and they did not clear the firewall...........

[Anonymous]

I know a guy who tried them on a '94-'95 Achieva and they did not clear the firewall...........

Then how exactly did he get them on?

[ikessky]

He never did. Guess I should have said "tried to fit them in a".

It's not magic making them fit though. A decent exhaust shop should be able to cut/bend/fabricate them to what you need.