Quote: Originally Posted by Maverick H1L The most expensive thing on your list would be dished pistons because the 2.8 pistons would create a compression ratio WAY too high for proper use. Not only that, but you'll need to pick up some pushrods, a crankshaft trigger, and do some work on your existing brackets to make them fit. Then, when you have everything together, you need to get equipment to modify your stock computer chip(s) so you can run the "new" engine properly. For example, I have a set of small-port 3100 heads from a 98 Malibu in the garage. Since my 3.1 already has 12cc dished pistons, I don't need to replace those. . i have just been looking stuff up and checking prices before i do/buy anything. so quick questions-all the 12cc dished pistons i can find are for different sized motors. do i need to find one for my specific motor or does it not matter. and if u have any idea, do you know what site would be better to look on then ebay

For the 3.4 block you need 3400 FWD v6 28.6cc dished pistons, otherwise CR will definately be too high(I looked it up).

For reference, there are several types of 3.4 liter engines: 1) 3.4(this refers to RWD when used correctly) 2) 3400 refers to FWD versions, and then 3) 3.4 DOHC, which is dual overhead cam variants.
1. Block, ideally with no top end, or lower end, but still with a cam in it and timing chain, reluctor wheel and such, but unfortunately the cheapest will probably be to buy a whole setup, and then try to sell the top end and pistons, the crank would be fine to use, 3400 fwd, or 3.4 rwd crank shouldn't matter, though the 3.4 would be slightly better because it wouldn't have the added rotational weight of a DIS trigger wheel on it.
2. 3400 pistons
3. crank if the block doesn't have one
4. ECM, I imagine that either a 3.4 or 3400 ECM would be fine, but I am not certain
5. wiring harness, I'm not sure, you would have to look into that
6. 3500 cylinder heads, 3400 would also suffice, but 3500s are a little bit better
7. 3500 intake manifolds, once again, 3400s would work but 3500s are better, a 3500 LIM will not work with 3400 heads, however with modification a 3500 UIM can fit on a 3400 LIM. Neither 3400 manifold will fit 3500 heads I believe.
8. Throttle body, fuel rail, FPR, and injectors, appropriate to whichever set of intake manifolds you have. Going to want the injector harness as well.
9. Gaskets, I'm not sure if you need gaskets for the bore size of the 3.4 or 3500, but probably the 3.4, definitely the 3.4 if you use 3400 heads, and probably still buy 3.4 HGs with 3500 heads, but double check. Make sure to get metal HGs, and metal LIM gaskets, the rest don't really need to be metal.
10. ICM and igntion coils, and if you have emissions you'll have to setup EGR somehow, if not I advise a block off plate and disable the code.
11. Exhaust manifolds/headers, spend the cash for headers IMO, not sure which ones will work though.

That's the bulk of what you need.

Just get a set of stock 3.1 pistons. That's all you need.

ONLY if you keep your current block, 3.1 pistons will NOT work in a 3.4...

1. 3.4 AND 3400 have the same crank. The DIS 7x trigger wheel is cut into the middle of the crank. You're better off getting a 3.4 short block as this will have provisions for the 7x sensor by the starter mount that the 2.8 and 3.1 RWD don't have.
2. Definitely 3400 pistons, or order a set that has a 24cc dish instead of 28.
3. Already went over the crank. However, to add something, you will need an oil pump drive from a 3.4 or 3100+.
4. Neither of those will work unless you can find an ECM from a 93 3400 OR 3.4, both of which are DIS and OBDI, the 16149396. 3400 DOHC ECM has DIS with SFI (this is the one I will be using, the 16196401), and the 94/5 3.4 has that screwy OBD1.5 and needs a flash reprogrammer and not a chip, because the chip is not removable.
5. Get a harness from a 90-92, or you might be able to keep your stock harness and add a couple of connectors for the DIS to it. You won't be able to keep your distributor.
6. You can get either 3400 or 3500 heads, but the 3500 heads have bigger intake valves. However, you can get the 3400 heads machined to accept the 3500 valves (.06" difference between the valves).
7 and 8. Get the entire manifold set (manifold, plenum, fuel rail) that goes with your cylinder head choice.
9. Log onto eBay and look up a seller called mizumoauto. They are currently selling the GOOD late model head gasket kit for around $60. This saves you some change.
10. Yes, you need the entire DIS coil pack setup, WITH CONNECTORS plus about 2" of wire on the connectors. You will also need the wire for the 7x sensor, which runs between the ICM and sensor.
11. Pretty much all of the headers available for our V6s won't work with the newer heads. You'll need to find something out for yourself. I've heard that the RKSport headers will work, but they're REALLY expensive.

well as of now, cant find any 3.4s at the junkyard or on craigslist. but i have a few months for the snow to melt before i start doing anything. 2.8 hybrid sounds more appealing anyway.

but thanks for the info guys. youve given me a lot to think about and more motivation to keep the 6 =D

quick question..would i need to stroke my 2.8 to a 3.1 for 3100 heads?

from reading recent posts i dont believe so but i just want to be sure.

No, but you WILL need to get dished pistons, as the ones you currently have are flat-tops and you're basically cutting the size of the combustion chamber in half (28.6 cc vs 48 cc).

If you have to change the pistons, change the crank too, it's really not that much more work for an extra .3l of displacement. Maverick do you if there is any other car that would have a RWD 3.4 other than a 93-95 F-body? I'm trying to look around but it doesn't seem like I'm going to have much luck.

You won't find any. AFAIK, the only other V6 engines GM used in 93 were the 3.1 FWD, the 3400 DOHC FWD, the 3.1 iron head FWD in the Lumina van (seen one of these weirdnesses in person!) and the like, the 4.3 in the S10 and Blazer and other trucks, and the 3.8/3800. For 94-5, the 3.1 FWD, and the iron head version were axed, being replaced by the 3100 and the 3400. I could be wrong about this, however, but I'm pretty sure the 3.4 RWD was only in the F-body.

Not sure about the change in crank to the 3.1 crank requiring notching the lower end of the block ever so slightly, either... Someone will chime in on this.

Are they hard enough to find that I'm better off staying with the 2.8/3.1, especially if I were to ever need another block?

That depends on your budget. Sure, a junkyard engine may be hard to find near you. However, there are usually a number of short and long blocks (without coverings for the long and only the block and rotating assembly for the short) on eBay and the like, some with free shipping. And, then, of course, with an even higher budget, there is the GMPP HT 3.4 crate engine. However, these aren't cheap...

Personally, I think it would be GREAT if someone were to come out with FWD to RWD engine mount kits.

Where can I find one of those?

One of which? The HT 3.4 may be able to be bought through a dealer, who will probably not give you a decent price. Check S10 sites to find out if anyone knows where to get some otherwise (the HT was designed as an upgrade to the 2.8 for the S10/Blazer series).

I would save the money up for a whole new engine, either an LS1, or a crate engine from edlebrock.