KrisW

iTrader: (5)

"Also got rid of the cruise control and heater bypass to make things a little neater "

AAAHHHHH!!!!!

What about those long roadtrips? heheheh Anyway, it looks great!

firstfirebird

iTrader: (3)

OK, got the 3.1 block back in for test fitting the headers...



Put some spare 3x00 heads and manifolds on...





Just wish the materials were here, I would have started them today

forkvoid

iTrader: (1)

I bet dropping that block in was the easiest one you've ever dropped, since it's missing the whole bottom end(or at least the pistons), due to the low weight.

grimmcs

iTrader: (1)

Speaking of headers............

Any word on my set?

bmxerboi221

Ive got a question... Ok with the 3.4 block, 3400 heads/intake/fuel injectors/pistons, 260 grind cam, and the 2.8 ecm with this hybrid run smoothly? I mean I know it might have like a small lope or whatever because of the cam but is like the idle going to be really jumpy or should it sit and stay in one spot while idling? Also which head gaskets do i need? Sorry not trying to hijack thread or anything just figured this might be the place to ask. Thanks

redlinex

Wow nice work there, i was originally was just going slap a turbo on my 3.1, but now im considering a 3.1 or 3.4 hybrid with a turbo , curious about something though, exactly what was the process you went through from switching from a distibutor to what you convert to? coil packs? and how did u manage the ecu with that swap? and did u use the 60 degree crank, rods, and pistons out of either a rwd or fwd block?? (well same spec internals that came normally with the 3.4), basicly what im trying to find out could i just pick up a 3.4l block out of like, lets say a 93 to oh 95 maro with its stock interals(upgrading to forged of course for boost) and slap the 3400 intake and heads on there, and switch to coil packs and be good to go?and im sure id have to splice some wires for the ignition change though huh?
oh btw was that a aluminum block u used? looks all nice and shiny lol

bmxerboi221

You will need to get pistons for a 2000+ 3400 i believe in order to have the right CR, but since your running a turbo you might want to look into the 3500 topend. It flows better than the 3400 and i think you can be safe running it with the 3.4 rwd pistons (cr is a lil high but some people want that) As far as the ignition stuff goes search for a thread call "switching to coil packs" or something like that. It should be fairly easy just a few wires to cut and splice

forkvoid

iTrader: (1)

Nope, it's just a standard 3.4L iron block, painted up very nicely. Matches the aluminum heads very nicely, giving it that "all aluminum" look.

redlinex

but i thought i read somewhere(i think it was in this thread, not sure)that the 3500 top end wouldnt fit on the 60 degree block, just the 90 degree block, did i read wrong? and can i find the 3400 top ends basicly on any late 90's to early 2000's grand am gt and grand am prix? just to get my info right before i go searching through junkyards for top ends.

forkvoid

iTrader: (1)

You've got it backwards. The 3500 is a 60* engine. The 2.8/3.1/3.4 is also a 60*. They fit.

firstfirebird

iTrader: (3)

The 3500 top end won't fit on a 2.8 or 3.1 because of the bore size.

A 3.4 block and 3500 heads will give you around 11.5:1 SCR, if you change that to 3400 pistons you get around 9.1:1.

The DIS swap has been posted with a diagram.

auto-x1990RS

ok, so from what i understand from this, is that i can't swap on 3500 heads onto my 3.1??? there isn't even a way to make it work???

grimmcs

iTrader: (1)

I don't believe you can bore out a 2.8 or a 3.1 to the 3.4 bore size...safely. So no there isn't any way to use the 3500 heads on a 2.8/3.1. Your best bet, if you want to do a 3x00 head swap is find some 3100/3400 and get a P&P done to them.

I knew it was something with the bore/chamber size.

firstfirebird

iTrader: (3)

The problem is the chambers on the 3500 heads will hang over the piston bores

curtalert89

im wanting to do this swap in my 88 camaro 2.8, i have a 3.4 block that in looking to get.to start out with mine im doing the 3.4 swap with the 2.8 accessories, there is a local salvage yard that has a couple of 3100's and one 3400, which heads would be better or are they the same. can you guys give me a list of all the stuff i will need to get to do this swap. and is there a way to swap out the intakes and plenium from 2.8 to a 3400 or 3500 without changing my harness?

Dakota W.

Has anyone suggested a Grand National motor?

fasteddi

iTrader: (2)

Thats a 90 degree motor so it would take a good amount of fabrication to make it work.

KrisW

iTrader: (5)

and Pontiac took that suggestion and put the Turbo Trans Am into production for 1989 with a special builder!

Anyway, it technically doesn't count as much of a hybrid since it was sanctioned by GM hahahahhaha.

I'm gonna do it anyway though!

Maverick H1L

iTrader: (8)

Need the top end from either a 93-99 3100, 00+ 3100 or any 3400 (same top end with different numbers on the upper plenum). Including heads, intakes, fuel rail, ignition coil assembly and bracket, and make sure you get the right EGR valve to match the intake. Also need to get a set of headers for the exhaust as the 3x00 won't fit.

As far as the harness, if you have the square IAC plug, you need to swap both the IAC and TPS connectors, the ignition module wiring, the oil pressure unit connector, and lengthen the fuel injector wires. The wiring for the throttle body will need to be made longer and probably run with the fuel injector harness. You can also install a single-wire connector from an oxygen sensor onto the dash coolant temp gauge/light wire and use the 3x00's 3-wire CTS. You will need to keep the wiring for the 7x sensor (in the side of the block by the starter) but lengthen the wires to go to the new location for the ignition assembly (assuming a 3.4).

KrisW

iTrader: (5)

Did firstfirebird ever get this thing going? I'm searching the forums for a different thread now...

firstfirebird

iTrader: (3)

No, I sold the motor and it never evolved into anything.

I have sold parts to a few guys that have done it with success, but not in 3rd gens.

right now we are swapping a complete 3500 in a 3rd gen and wrapping up a hybrid build in a 4th gen, though.

firstfirebird

iTrader: (3)

Put a 3400 top end on a 3.4 (stock RWD pistons) and your compression will be extremely high.

There's a customer in Tampa Bay area that used 3.4DOHC pistons and 3500 top end (12.6:1) and he runs on pump gas with the heavy cam and of course good tuning.

The heads on a 3100 and 3400 are the same after 2000, so go for a late Grand AM at the wrecker.

As far as I know, the TPS and IAC will plug right in (at least they are the same on my 'bird as the 3400). The fuel lines will need extending and/or adapted since the FWD fuel rail and the chassis lines are both female quick disconnects.

The front timing cover has to be modified for the LIM t-stat housing to clear.

The 3.1/2.8 accy brackets can be used for the most part with some re-drilling of the mounting holes, but the alternator may have clearance issues with the FWD valve cover. I had to make a new steel bracket for it to clear. The 3.4 brackets work a little easier, but if you are keeping A/C, then the lines and wires will have to be moved to the passenger side and the 3.4 compressor to be used.

The ICM wires should reach fine, just take them out of the loom on the 3400, I know the 3400 wires reach just fine if you mount the coil packs like the 3.4 has them.

The throttle cable will need to be longer and you will need to figure out a way to make it pull from the front.

The FWD doesn't use a 3 wire CTS, or it would be easier. There is a CTS from the iron duke you can use that has 3 wires, the 3400 uses a 2 wire for the PCM and a single wire for the cluster. It's just as easy to tap the head or t-stat housing and use the sensor that's on the 2.8.


If you would like lower compression, you can use 3500 heads, or swap the pistons to 3400 pistons.

Here's the hybrid we are working on now. Ig nore the Accell coils, they aren't going on the build. The customer provided them and were just stuck on there for the pics.

kmcn47

sub'd

fasteddi

iTrader: (2)

For the compression factor. 3400/3100 heads/intakes on a 3.4L block/pistons will net high compression. But a 3500 heads/intake will not?? I got lost there. Thanks.

KrisW

iTrader: (5)

I'm betting that the 3500 heads have larger combustion chambers, which drops the compression if used with the 3.4 pistons.

34blazer

looking at ~11:1 on the 3.4 iirc

fasteddi

iTrader: (2)

With the 3.4 pistons/ 3500 heads? Or the 3.4L pistons/ 3100/3400 heads?

34blazer

with the 8cc iron head pistons, 3500 heads. the 3400 heads would put compression in the 12's

firstfirebird

iTrader: (3)

3500 heads, .060" HG's and 3.4 iron head pistons make 11.56:1 if the heads have never been shaved.

3400 heads have much smaller chambers and will net you far more, and the iron head gaskets (.050") give better quench/squish but are over 12:1.

Maverick H1L

iTrader: (8)

1. Yes, I know. Never said anything about 3400 top end on a 3.4, just the 3.1 as was assumed above.

3. Already said that.

4. Not on my 87. Had to swap out the broken connectors to use the 3.1 throttle body with IAC and TPS. 2.8's IAC is a square connector, and TPS is a flat connector, both with pins similar to that of the O2S. Same setup as I've seen on other 2.8s at yards.

7. Go for a throttle cable from a mid-90s Grand Am. I think it has the Quad4 in it (at least that's what I'm assuming the intake was from that was in the back seat). It's like 4 feet long.

8. Tell that to the 3-wire CTS I got in the manifold from a 98 Malibu. And the harness for the same I got the pigtail out of.

firstfirebird

iTrader: (3)

4. My 'bird's a 90 with 3.1, plug was the same.
7. Yeah the cable was that long from the GP as well. I usd the TrailBlazer cable in the 'bird, but with the TB adapter in the 4th gen in the pic above, it was too stretched and was afraid it would kink.
8. Didn't say the duke was the ONLY 3 wire, just that it works. I found it easier to re-tap the blocked 3500 passage for the RWD sensor.

KG427KG427

iTrader: (1)

Does any do the work on something like this in California I want a 3.1 to 3.4 build I would pay PM me!

Great read and great work.