Throw $$ @ 3100? Or go 3400?

[flyhigh2chill]

Just a few questions… I’m lookin for ideas, opinions, whatever… My 96 GA 3100 needs a new LIM gasket. (whats new) She's got 92000 miles. I have a ported TB and upper and lower IM, intake, exhaust etc. I’ve been thinking about dropping in a 3400. Or while things are torn apart, should I go a little farther like cam and heads on the 3100? Whats the best value? Either way I’m going to need pcm work as well. Probably go DHP. I’m fairly familiar with the mods available for GA’s. Just want to hear others ideas!!!

[IsaacHayes]

cheapest is 3400 heads/intake manifolds. or just manifolds but make sure you have roller rockers or you'll have to clearance the LIM. I'm putting large 3400 intake manifold on mine, alogn with a 3500 upper. If the motor isn't damaged from coolant in the oil it will run for another 100k if not more. Depends on how far you want to go. I'd say swap intake manifolds as you'll have to take em off anyways and put a metal felpro gasket and you'll likely never have to take it apart again.

But if you want a fresh 3400 you can go that route too but it's more extreme.

[sharkey]

depends on what you want to and are able to do. swapping a motor takes a lot of work and a place to do it. if there is no damage to the motor from the coolant, keep the 3100.

what i would do is put a 3400 or 2000+ 3100 top end on it. the large ports will help it breath better. id also do a 3 angle valve job, ls1 springs, and even get em ported if your able to. a 3500 plenum would be a good idea aswell.

[IsaacHayes]

I almost went with 3400 heads, I woulnd't have the rocker issue (i dont have roller rockers) and have a bit better flow with the larger valves. But the cost would end up being more than a whole 3400 so I just went with the intake manifolds. Gaskets add up the cost in addition to parts.

If you do the whole 3400 top end, you basically have a 2000+ 3100.

[PCGUY112887]

The 3500 upper intake is a good idea as well as noted above... only bad thing is a new TB from here is just so damn expensive (for a TB that is, great product though). And I don't know of any other TB's you could pull from a yard that would work for cheaper.

[IsaacHayes]

On here the TB adapter will accept a stock TB as well as the 65mm unit. That's what I'm doing. You gotta cut your own TB gasket out of thin card board or use silicone RTV for a gasket though.

[flyhigh2chill]

Thanks for the replies guys! So is the stock 3400 manifold going to flow much better than my p&p 3100 manifold? Should I p&p the 3400 to make it worthwhile?

[MMGT1]

Thanks for the replies guys! So is the stock 3400 manifold going to flow much better than my p&p 3100 manifold? Should I p&p the 3400 to make it worthwhile?

P&P is ALWAYS a good idea

[Azrael]

The 3400 manifolds, untouched, will outflow the old small-port 3100's even if they're ported.

[blackbombshell95]

I bought my 2003 3400 from a buick redevois for $200 with 32k miles.

[flyhigh2chill]

A few more questions. I have the (m) vin number. does my 96 3100 have roller rockers? Also do I need the second design IM gaskets with push rod guides or not? I want to get my parts together before I tear it apart!