Well I am new to this board. I am curently looking at my options to my next project and I got some questions about turbo charging a SL6. Its would a 225 in a short wheelbase van.
The frist one is 3.8L electronics seem to be a good start, but wouldn't you need a turbo computer?
I thought about using a 2nd gen turbo supra electronics. Has any one tried this or is there to complicated?
What pistons have had good results?
Can stock valves take the heat?
For turbos I thought of using a large turbo .
IC from a cummins diesel.(or something else very large)
Custom intake.
Forged turbo pistons with 7-7.5:1 compresion.
15-18psi of boost.
Electronics would be the hardest part to achive the amount of boost that I want.

As for what computer to use, there was a particular GM ECM (I can't remember which models it came on, and I'm not sure it was the 3.8 Turbo) that used an EPROM system and can handle boost. How to reprogram it is very well documented, and I heard from a guy on another board who is using this to control a turbo Honda Accord (which irritated a lot of Honda guys that he's using GM parts!) that a GMC Syclone computer program would be a good starting point. However, the roll-your-own MegaSquirt computer is so cheap - and intended for tuners - that it may be your best bet. There's been some talk of it in the Engine forum here, in fact, and I think somebody here (Lou?) may be running it on a slant six. I don't know much about the 2nd generation Supra computers being very tunable at all.

A large diesel turbo would be a very poor choice for a slant six. Bigger isn't better, necessarily. A diesel truck turbo would probably take too long to spool and may never even deliver full boost. I recommend getting a copy of <i>Turbochargers</i> by Hugh MacInnes and <i>Maximum Boost</i> by Corky Bell. These books do a good job of explaining how to size turbochargers. A too-large turbo is an even more problematic tuning issue than a too-large carb.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

FYI, I have been running the laptop-programmable MegaSquirt for about 4 months on my '64 Dart with only one minor problem that was my fault. The kit comes with a 2.5 bar MAP sensor that will work with up to 1.5 bar boost (about 22 lbs).

I like this computer, and the parts/kit are only about $200.

Search "megasquirt" on this site and you'll find a lot to read.

I'm with Matt on the turbo too - don't get one that's too big.

Cheers,

Lou

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Home of Slant6-powered fun machines since 1988

Hi everybody, been lurking but I had to chime in on this one

Skip the Supra electronics, they are very limited in what you can do without adding a ton of very expensive piggy-back stuff, some of which is no longer even available. The AFM is very restrictive and switching to speed-density is also an expensive proposition. By the time I had my Supra running well at high boost I had more money into aftermarket band-aid electronics than I did in the rest of the car! This is one of the reasons I now own the Duster.

I guess I didn't chime on this one when it was first posted because I hadn't had enough turbo time to be real sure that my set-up would work well. But now, with well over 1K miles on it, I can report that you can run an '84-'85 Buick turbo using the same EFI computer (ECM) and basic set-up described at http://slantsix.org/articles/dibiase_ef ... ersion.htm The only changes I had to make were to use the turbo Buick injectors and '84-'85 turbo MAF sensor. I'm running 8lbs of boost with this set-up. I am planning to eventually try using the '87 turbo ECM because it has some nice additional features, but for now I'm having too much fun driving this thing! http://hometown.aol.com/bbobbias/page1.html
Bob D

Hi Lou,

I just purchased a 65 Barracuda, and I am planning my modifications. What is your megaquirt set up? I am looking at a custom tube manifold, and multiport. Are you running throttle body? What do your VE tables look like?

Thanks

Greg

Greg,

For now, I am running TBI, and I expect the fuel map to change when I switch to MP-EFI - hopefully in the next 6 mo. Check out this thread first, and I can add updates as needed -

http://www.slantsix.org/forum/viewtopic ... megasquirt

I can post a fuel map if you like. Check out this site for info on the MS computer - http://autos.groups.yahoo.com/group/megasquirt/

The main advantage of MS is its cost, and that you build it so you know how to fix it if it goes wrong. If I had lots of money to spend, I would have probably gone with Electromotive or Haltech. The MS crew will hopefully soon have DYI spark control/DIS kits as well.

Cheers,

Lou

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Home of Slant6-powered fun machines since 1988

Hi Lou,

Thanks for the background. I have been lurking at Megasquirt for a few months now. I am just getting off of Active Duty with the Army, and I needed something to keep me sane the last couple of months. I have always wanted an old Mopar, and the combination of a Slant 6, Megasquirt, and a turbo are right up my alley. So your project sounds very similar to what I want to do. I have to fix the brakes and steering on this car before I do much else, but any tips, tricks, etc that you can pass on, I would appreciate.

How come you haven't posted on the megasquirt success stories page?

Thanks,

Greg

Greg,

I'll keep things updated as much as I can. Moving next week, so hectic times.

They should have put me on the success stories page and I was on there at some point... Have to look into that.

Lou

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Home of Slant6-powered fun machines since 1988

As for a /6 Turbo project, what's the best source of pistons and rods that'll live in this environment, and would I have problems using the later model smaller chamber head.

I just re-read the articles and didn't see anything, but I could be overlooking

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"When applied at precisely the right time, Ignorance is a powerful tool, usually even surpassing knowledge" E.J. "Michigan Madman" Potter.

If you will be running about 10 psi or less, you can live with stock internals and any head you like. Be careful with fuel metering and timing retard, of course.

I love that EJ Potter quote - cool dude.

Lou

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Home of Slant6-powered fun machines since 1988

Lou, I want to take you up on your offer of posting your fuel map. Heck, any calibrations you can send would be great. I just read the roms howell gave me and I want something to compare to.