My 3100/3400 hybrid build...need advice...

[karateguy62]

Well I have a 95' 3100 V6 and Im doing a 3400 top end swap. I have the following parts:
3400 throttle body
3400 Upper intake manifold
3400 to 3100 EGR adapter
3400 Lower intake manifold
3400 Heads
3400 roller rockers

I plan on having the manifolds and heads ported...What else should I do to the engine since I will already have it torn apart to this point??? And if possible could links to the parts be included? Im not missing anything off my list am I? Thanks for the help.

[karateguy62]

alrighty got some views but no responses...

[sharkey]

is the motor out of the car??? if it is, may aswell throw a cam in it. iirc, miltzy makes a cam for the gen 3 motor.

[Azrael]

Don't forget new gaskets (especially the revised LIM gaskets) and headbolts.

Swap the headbolts for ARP studs if you plan on tearing the engine apart again in the near future since they're stronger and reuseable. The part numbers for those are somewhere on this forum.

[karateguy62]

The engine is in the car....I havnt started on the project yet but I might end up getting a whole 3400 to swap eventually...but i was thinking new valve springs? I dont know pushrods? are there other things that should be replaced that will help performance?? Also can I keep the same pushrods...ive heard from some I need different ones, if so how do i find out which ones I need?

and yes the revised gaskets will be a must!

[ihatemygrandamg]

If your getting the heads done you should get some ls1 or ls6 valve springs also.

[SappySE107]

If you use a steel cam, you need to do something about the iron gear on the oil pump drive/distributor drive. Cammotion doesn't recommend using the stock iron gear as that will cause problems.

"This melonized steel is required on all crate engines and roller camshafts that are made made of steel. If engines are assemblied not using this gear it may affect your engines warranty."

Thats the GM part for a big block using a steel cam. I haven't found anything for the 60V6 engines yet. I would go with a regrind over a steel cam right now unless someone else has a part we can use.

[karateguy62]

If your getting the heads done you should get some ls1 or ls6 valve springs also.

Know where I can get some from? What exactly will this do for the car? What about pushrods?

[SappySE107]

What kind of porting are you talking about? What powerband are you wanting from the engine? The springs depend on your cam and how high you are going to spin it. GM sells the LS1 springs pretty cheap and those are a good upgrade for a stock cam. If you go with a regrind or a billet cam, you will need to measure your pushrod length needed with a checker. You will probably need to make one as I haven't found one for under 6" length yet. The LS6 springs are stiffer (you need the yellow ones, also knows as the LS2 springs now). Lingenfelter sells them in sets of 16 for 65 bucks. You will need different seats/seals for this though. The Comp springs I have on the store here are in between LS1 and LS6 springs, and will work with the stock seat/seal set.

[karateguy62]

As far as porting just opening it up to breath better...Im not touching the cam right now....just the heads up!

So what other mods should I consider? maybe 180 thermostat? I really dont know at this point...since I have this 95 obd crap I dont even know what I can do to see the best results from just a top end swap...I just want a little more pep out of this engine for now till I do something drastic later down teh road...

[karateguy62]

will changing the springs or pushrods even do me any good then since the cam will be stock?

[ihatemygrandamg]

Well even with stock cam I would get better springs with ported heads. But there are soo many options you can consider when getting headwork done. Mod wise are you looking for advice on top end parts or performance parts in general for the 3x00?

180* is fine, I always ran much cooler after but I also have a reflashed pcm with many parameters changed to help that. Also, the 60*v6 store has 1/2 intake spacers for not much more than felpro uim gaskets. I have them and my uim stays much cooler.

[karateguy62]

Mostly just the top end parts....since i will be tearing apart the top end only as of now I figure while its apart i should upgrade as much as possible....with the 1/2 intake spacers do you still need gaskets??? Is the only benefit of having them keeping the UIM cooler?

[SappySE107]

I am out of them right now though I hope they get made again soon You don't need gaskets with them and yes, its benefit is to keep the heat from soaking into the plenum.

[karateguy62]

alright anyone else have some mod ideas??