3400/3500 top end swap on a 2.8

[Tonglebeak]

Ok thanks for showing me that.

Just an update: I got the heads from BigJoe (very nice condition I must say). I got a 3400 plenum off ebay. It came with a throttle body and a couple of sensors I believe. I'll get pics when I find my camera...

ALso got the lower intake manifold and the exhaust manifolds+xover pipe.

So I've pretty much got the engine parts set. I just need to figure out a downpipe for the car, as well as the other tidbits on that hybrid website (different hoses and such). I also need to figure out how I'm going to get the linkage setup for the throttle body. Also need all kinds of bolts, and all gaskets.

It's coming together...

Oh and I forgot about the camshaft. I've heard that there's a company called Delta Cams that can make an equivalent of a Crane 272, for half the price? Has anyone had experience with these guys?

And finally I'll need a chip tuned for the top end, the cam shaft. Anyone know if it's also possible to tune the chip to use the 3400 injectors (I already have them, came off an engine that only had 80 miles on it)?

[3100 MPFI]

Ok thanks for showing me that.

Sure. Anytime.

Just an update: I got the heads from BigJoe (very nice condition I must say). I got a 3400 plenum off ebay. It came with a throttle body and a couple of sensors I believe. I'll get pics when I find my camera...

The throttle body should have the IAC (idle air control valve), and the TPS (throttle position sensor). If you use the stock 2.8 wiring harness, you will need to lengthen the wires for them. As long as you shrink wrap them, they will be fine.

ALso got the lower intake manifold and the exhaust manifolds+xover pipe.

So I've pretty much got the engine parts set. I just need to figure out a downpipe for the car, as well as the other tidbits on that hybrid website (different hoses and such). I also need to figure out how I'm going to get the linkage setup for the throttle body. Also need all kinds of bolts, and all gaskets.

You need to go to a junkyard and find either a Cutlass Ciera, or a Buick CENTURY with the 3100. You can get the parts off of it, and see how it is all set up. You can get the hoses new from a parts store (which I recommend). As for the downpipe, your best bet is still getting a downpipe from a Ciera or a century 3100 and using it.

It's coming together...

Oh and I forgot about the camshaft. I've heard that there's a company called Delta Cams that can make an equivalent of a Crane 272, for half the price? Has anyone had experience with these guys?

Have not used them, but be sure you do NOT get a 3100 camshaft. That will be for ROLLER LIFTERS. You will need to get a 2.8/3.1 camshaft that is for the FLAT TAPPET lifters.

And finally I'll need a chip tuned for the top end, the cam shaft. Anyone know if it's also possible to tune the chip to use the 3400 injectors (I already have them, came off an engine that only had 80 miles on it)?

It depends on the 3400 injectors. If they are the fat ones that look like the ones you have now, then yes. If you have the skinny ones that the newer cars use, then probably not. They might throw in too much fuel, and seeing you are basically going to have a 2800 it might flood your car. You are best off using the stock 2.8 injectors and programming them to fire longer, or even getting 3.1 or 3100 injectors. I would get the 3100 ones myself.

[IsaacHayes]

If you get a chip tuned for the larger flow rate you can use whatever injectors you wish.

[Tonglebeak]

Alright, so tuning will be everything then...

BTW, will my stock 2.8 valve covers bolt onto the heads? (hopefully i'm not mixing up my terminology here).

[3100 MPFI]

yes they will, BUT you do NOT want to use them.

In your 2.8, the oil filler cap is mounted to the LOWER INTAKE, but in the 3100, it is mounted to the FRONT VALVE COVER. If you use the 2.8 valve cover, you will not have an OIL FILLER. Also, the PCV valve on the 2.8 is mounted to the REAR valve cover, but in the 3100, it is on the FRONT valve cover. If you use the 2.8 covers, then you will not have an OIL FILLER, and you will have issues with your VACUUM lines.

Here is a comparison. Also the breather line is different. It goes to the front valve cover on the 2.8, but to the rear valve cover in the 3100. I will see if I can get pics of them.

[34blazer]

or you can get a hole saw and install an aftermarket oil filler cap

[3100 MPFI]

Why do that when you can just get the parts from a junkyard for less than the price of the hole saw, and even the new filler cap, that already has what you need.

Here are some pics for comparison.

FRONT OF ENGINES:

3.1 MPFI (same as the 2.8 MPFI in all of the important areas)


3100 SFI:


REAR of the engine:

2.8/3.1


3100

[34blazer]

some people like the older gen2 vc's i guess

[3100 MPFI]

I have a soft spot for the GEN 2 in general. That is why there is no forboding doom..... er..... I mean PLAN on doing a gen 3 swap in my 1990 STE. I think I am going to keep it a 3.1 MPFI.

[Superdave]

Is it really that much of a challenge to route a hose to the rear VC on a gen3 engine for the PCV and just use a funnel to fill the oil through the little hole in the front Gen2 ?

That was my plan



They do fit, not sure on clearances to the rockers with a large cam though...


The only reason GM put the PCV on the front valve cover was for easy access, with the gen2 engines it was a major PITA. Flipping that hose around will give you an easy port for the FPR as well, if you guys would like i'll toss the top end back on my engine and route the lines so it would all work fine.

[ForcedFirebird]

Holy crap, that's a looong filter, Dave, lol. What do the kids call that WAI?

[Superdave]

Holy crap, that's a looong filter, Dave, lol. What do the kids call that WAI?

Lol!

It came off of a local guys Mustang, it's a real K&N, got it for $10 used. Flows MUCH better than the dual setup i was using before.

I'll be running a 3.5" intake tube down into a cozy spot below my battery tray for next year...

[IsaacHayes]

Hahaha Dave is filter crazy!

Dave, does the hard coolant neck coming from the pump to the heatercore on the gen3 clear the gen2 covers? I don't think it would. Those covers I wanted to use with my plenum too.

[Superdave]

Mine's been hacked up pretty good but iirc the neck snapped down into the timing cover ok, just needed to be turned a little for the hole to line up.

I'd like to get rid of that line completely, gonna try to make something for that next spring.

[3100 MPFI]

Are you talking about removing the metal line that goes along the underside of the valve cover? In the W-bodies, it had that line, but I didn't want to use that in my Cutlass Supreme. In the W-bodies, I think it goes across, then goes to the heater core under the throttle body. The part under the throttle body, also had 2 little inlets/outlets that attached to the throttle body.

I got this one off of a 3100 Cutlass Ciera. It has the heater neck going towards the front of the car like the older W-body GEN 2 engines do. I just hooked it right up, and when I got the factory oil cooler, I tapped into it. I know the Ciera also got one that has an extra outlet on it just for the oil cooler (I am looking for that one still).

Don't know if it is exactly what you are looking for, but thought you might want to see it.