New engine swap plan: GM 4.3L V6

[jk651]

So after being talked out of swapping in an S38, I have finally come to terms that it's too expensive to get the power I want out of my M62 and that a non-BMW engine is the only realistic route for the power I need. However, instead of doing the LSx engine swaps that seem so popular, I have decided that a turbo 4.3l is the way for me to go. Their commonality with the classic Chevy 350 engine means that pistons are cheap and easy to find in any compression ratio I want, the Vortec heads flow very well, the compact size of the engine means lots of room under the hood for a turbo (or two!), and I already own a donor engine from my offroading Blazer, which is getting a 383 stroker. I have a t25 turbo laying around from my Buick Grand National phase, and fabricating the exhaust is going to be the hardest part. I do need to buy a transmission, but that shouldn't be too difficult to find. My biggest worry is getting as much of the stock BMW gauges and electronics as possible to work. 600 HP should be easy, 850 with some massaging. I know some of the GMC Typhoons are pushing 1100hp, but I don't have my goals set that high. Also, there will be a considerable weight savings.

[jakermac]

I've thought about that on more than 1 occasion as well. Is the V6 aluminum block? I like the idea of the rearward weight shift of a short V6. You could even pull off a T5 tranny if it stayed NA.

[jk651]

It is an iron block. GM bowtie did offer a performance aluminum block for a while but they were quite expensive and now discontinued I believe. Also, it was intended for dry sump only and had no provisions for an internal oil pump.

[sweetcorn360]

I don't see why you couldn't get everything to work. I've done the ls2 swap and have most everything working, don't care about everything though. I've seen other guys do complete functioning conversions. The turbo setup would be sweet and you might be able to avoid the steering shaft problem we see on the e36. I'll be looking forward to see what you come up with. Ask questions if you need help with sensors, somebody is bound to know.

[jk651]

I know I will figure it out, but I haven't really seen a tutorial for the LS swap, I don't know how to interface the GM ecm with the BMW electronics, wiring, etc. I'm not overly concerned, but I've never done a swap of this nature before. I did an M50 into an e30 once, but that was a lot easier because it was a BMW engine into a BMW, they were both 6 cylinders, and I had the help of Zionsville Autosport/ Project Orca. Will the tach read correctly since I'm putting a 6 cyl into a v8 car? Those are my sort of concerns. I'm guessing the OBC will not work afterwards. Fabricating mounts and stuff will not be a problem, that's the kind of thing I find fun.

[sweetcorn360]

The ls1 ecu you can change the tach out put. The ls2 you can not, so we use a dakota digital converter to change signal. If your ecu can not do this then the dakota will.

Speed sensor comes from the diff on the e36, I'm guessing same for you.

Our water temp for the gauge, we install a bmw ect sensor on the opposite head that gm didn't out their sensor in. Must likely they will have different resistor values so this is important for agood gauge reading while the ecu gets the right readings from its sensor.

If you have oil pressure, you will need to do similar... add a bmw sensor.

what year/model are you doing this to by chance?

[gunmetalgreen]

[QUOTE="sweetcorn360;27609689" what year/model are you doing this to by chance?[/QUOTE]

I also am interested, pictures??

[EMC]

I think someone recently started this swap in an E36, but quickly stopped because packaging was a mess. Hopefully, you have better luck in the 540i. It would be a pretty cool swap to see up and running.

[Fender13Bender]

I've had a 4.3...it's nothing to write home about. They leak everywhere, and they have lots of little problems. Sure, they'll run forever on anywhere between 2-6 cylinders, but they just plain suck.

[1ofakind71]

I am in the home stretch phase of putting the GN swap in my e36 and it has been quite an adventure, as I don't think anyone has done it in the e36. I did fire it up just to make sure everything was correct but I haven't broken it in yet. A 4.3 shouldn't be too hard to do especially if you have the fab skills.. good luck with your swap, I will be watching out for your progress.

[undr8dempire]

Good for displacement, but the motor is mediocre IMO. I realize with boost it has potential, but I'd prefer a 3.8L GM turbo over the 4.3L

[09bmw335i4me]

So I'm looking for an update to any of the Buick transplants especially in an e34. Just bought my $300 92 e34 sedan project car and very interested in the GN swap concept.

[TH3 Shifty]

Might as well do a standard 350 V8 for the same cost. The 4.3 is weak, any aftermarket stuff available and the 350 is the complete opposite. TONS of aftermarket easy to make power and simple engine to fix

[Tim Mc]

Very few folks pursue GM 4.3 liter V-6 for performance.

[TH3 Shifty]

the only 4.3 worth a damn was the Syclone/Typhoon 4.3 turbo engine... but even that engine was poor without serious upgrades.. ive had 3 typhoons and all required major updates

[jrode34m5]

Good for displacement, but the motor is mediocre IMO. I realize with boost it has potential, but I'd prefer a 3.8L GM turbo over the 4.3L

the 3.8l supercharged than came in the pontiac bonneville? Is this engine better than the 4.3l. ? interested in any info about this engine. thanks

[TH3 Shifty]

Weak. No aftermarket support. Only 3.8 that has a good base and good aftermarket support is the 3.8 turbo found in the Buick GN and Turbo Type Buicks

[putnampunk]

Did this get done in the end? I lost my M62 engine and tempted to get a GM v6 or v8 in there for Lemons