3.4 / 3500 Hybrid Build W.I.P.

[60V6Bird]

Okay. I'm done being a noob, and ready to take the plunge into my first 60*V6 engine build.

Let me kind of introduce myself. I've been lurking here a bunch, reading what I can and trying to take in as much as possible, however I still have a bunch to learn. I have a 1992 Pontiac Firebird that less than a few thousand miles ago I swapped a remanufactured 3.1 into it. (All stock.) Well, I'm really looking to finally start building this car how I want. I plan on roadracing and auto crossing the car, which is what leads me to stick with the lightweight and unique 60* platform. Here are my goals.

• Naturally Aspirated.
• At least 200 HP to the wheels, however I wouldn't mind having 220-240ish if the extra work wasn't that far of a cry.
• Some sort of aftermarket ECM, one that either I can teach myself to tune, or one I can easily have dyno-tuned. (Megasquirt I'm thinking?)
• It needs to be Reliable and Streetable, my two biggest concerns.

After trying to have hope that I could meet my goals with a simple iron headed build, I realized it just wouldn't happen. From reading and research, my best bet seems an iron block 3.4 from a Camaro/Firebird, with a 3500 top end, much similar to ForcedFirebird, however I want to stay naturally aspirated.

Before I go out and buy a 3.4 shortblock and start, I'd like to ask for input from all of you knowledgeable people. What do you think? What would you do? How hard is this all really gonna be? I'm not the best fabricator, but I'm sure everyone here will be willing to support me. I'd like to have everything new in the build, IE block stripped to nothing, acid dipped, new cam bearings, main bearings, etc. What should I look for in a 3.4 block? Basically all the noob things like this. I plan on posting my pictures and progress here, along with the many questions I'm going to have, so that I can not only help myself in this journey, but anyone willing to follow in my steps.

Thanks in advanced!

[ForcedFirebird]

Right on!

If it's a complete rebuild, start looking for a motor that at least turns over, and go from there. I paid a little much for my shortblock, but it came out of a running car. Still needed the crank to be polished and ALL new bearings, but I got a good deal on a 3.1 crank from ARI that someone had and never used (with Clevite bearings).

My build is N/A, so youu could actually do the same type of build with stock heads (ported) and high compression.

You have OBD1, and that can be tuned yourself, but I am unsure how to go about the DIS swap with it, Ben could probably help you there since I went with a standalone ECM.

[60V6Bird]

Quick quesitons, hehe.

Is there any difference from the 3.4 and 3.1 crank?

Whats a DIS swap?

I'm still leaning towards a standalone ECM like the Megasquirt because I think later down the road, the more options I have, the better the end result would be, and from what I hear, tuning OBD1 is a huge PAIN, however if in the end it would be easier to use the OBD1, I might do that.

[Joseph Upson]

Considering the power range you are shooting for your time and money would be better spent on a low mileage 3500, and using the money planned for machine work on the parts in the store available to help swap it in place instead. I know I'm speaking from the stand point of someone having fabricating skills but relocating the starter should not be a real issue at all even if you have to add a small angle to the block on the right starter pad area.

Modifying the mount pad to bolt the engine mount brackets to the FWD block or making adaptor plates shouldn't be that difficult especially since you will have both blocks for side by side comparison.

It seems like a much better approach to me since you are already speaking of using the 3500 intake system, you may as well get the extra .1 litre along with the additional improvements over the 3.4. The engine is already 200 hp, 220 lb/ft. with a cam and a little head work you'll have more than you've stated you would like especially if you add headers.

I've performed several swaps and I've "taken the back door to get to the front yard" more times than I care to admit. I encourage the guys on the Fiero forum looking to do a V6 swap for more power to go ahead and start with a higher performing V6 instead of trying to build the old iron head motor up to the fwd motors performance level.

Still the fwd engines are catching on slow over there, and some members are spending on aftermarket parts and engine preps far more than what it would cost to just install a complete aluminium head motor and still ending up with front wheel drive stock level engine performance.

I'm avid about this issue because I've blown a lot of money in the past from ignoring the best route to producing more power. I spent $150 on a like new 3400 short block instead of $250 for the complete engine so I could put the Fiero intake and iron heads on it and choke it down about 30 hp or more before turbocharging it.

Think about it.

[60V6Bird]

I'm open to all opinions, and thanks for the input Joseph.

Apart from relocating the starter, modifying the mount pads, and making adapter plates, what else is involved in using the 3500 in a RWD application?

What all is involved in relocating the starter, that sounds like some major block modification, I'm not sure if I'm capable of that.

Thanks for the input, and don't mind all the silly noob questions.

[ForcedFirebird]

Yeah, Joseph, I know what you mean. Just after I paid for my 3.4 shortblock, 3500's started popping up everywhere for cheap.

If you spend some money on a tubular k-member, the only thing needed for the FWD swap is a remote oil filter housing and one custom motor mount (starter stays put). Driver_10 did a 3400 in a 4th gen Fbod (he's a member here).

[60V6Bird]

To be honest, I have yet to find a 3500 at any of the local wreckers, or online such as eBay, even 3500 parts I have yet to find.

As far as tubular K-Member, I have yet to see Spohn, or UMI offer one with V6 mounts, yet would that be the one I use?

Thanks again for putting up with me guys!

[ForcedFirebird]

car-part.com is where I found them for reasonable prices.

You have to fabricate a motor mount no matter what when you use a complete FWD engine. In the future I would like to use the heads I'm building on a full 3500 and the Spohn then modify it to work.

[IsaacHayes]

https://www.car-part.com

[2.8RS]

www.car-part.com

I'm glad you posted that link.

[ForcedFirebird]

I'm glad you posted that link.

Hey, it was in post #8 (but Isaac gave me the link in the past )

I was going to call All-Pro tomorrow to order the 3500's I need, and was going to ask him about your 3.4 for you - that's why I asked if you had access to a forklift. They will deliver the motor for cheap if you have a commercial shipping address .

All-Pro used auto parts of FL = cheap running motors

[60V6Bird]

Now I'm really at a toss up here. I can't decide which to go with, a complete 3500, or a Hybrid. A lot more cost and work involved with the 3500 it seems, but in the end that'd probably be the better motor to go with, however the hybrid seems like it'd be the easiest route.

Oh boy, what have I got myself into, hahaha.

[Superdave]

Camaro 3.4 with a 3500 top end, Crane H272 cam and some headers will get you to your goal.

the 3500's power comes from the heads, it's got other advantages but the majority is the top end.

streetability is mostly in the tuning, there is no need for an aftermarket ECM, with the right tools you can tune your stock one (although you'll have to run DIS with this setup).

[ForcedFirebird]

streetability is mostly in the tuning, there is no need for an aftermarket ECM, with the right tools you can tune your stock one (although you'll have to run DIS with this setup).

How easy would it be to modify a 7730 to run with DIS?

[Superdave]

How easy would it be to modify a 7730 to run with DIS?

Not sure.. since my '7730 runs the DIS just fine


you may need to just pick up a Jbody engine harness, probably the easiest way. Although I bet it's possible to modify the stock Camaro V6 harness to work with the DIS, probably swap around some pins on the ECM connector and put in the right memcal.