3100 UIM on 3400 LIM

[3400beretta]

I tried searching, I can't seem to find the answer, will an older ('94) 3100 uim fit onto a '99 3400 lim? The reason I ask is Im trying to make my car pass emissions, and we welded up the egr passage on my 3400 manifold. I have a 3100 sitting here and before I do all the work of pulling it off, I thought I'd ask. Also the '94 egr is the same as a '93 and earlier digital egr correct? So I won't need an adapter?

[bszopi]

No, it will not work. If you look, the 3100 upper has 12 bolt holes and the 3400 only has 6. And, they aren't in the same locations. And then is a chance that since the 3400 lower has such bigger ports that the 3100 upper may not cover the ports completely - ie, huge vacuum leak.

[3400beretta]

Thankyou. The engine is not at my house, or else I'm sure I would have noticed the different number of bolts. Lets hope anyways.

[IsaacHayes]

A 3100 UIM from 2000+ (I think 1999 too) is the same design however as the 3400 and will work. But the older "small port" 94-98 won't.

So you'll need a large port manifold and an EGR adapater for which ever year you go with. Check out the store here and look at each adapater to see the years.