Inliners International Forums General Discussion Blown and Injected Buick turbo for my 250

Ty sir!

I've decided to let the ecm control my timing.. especially retard during boost and such. What initial and total timing do you guys recommend for the inline 6?

Can you tell us more specifics about the engine like compression, cam, fuel type you expect to run, etc...

72 Chevy pickup. All stock, .30 over rebuild. Premium fuel... most likely going to set up a water methanol kit later.

Hei distributor mechanical advance locked out. Vacuum advanced not used.

I had the same turbo so my Nova but it would not clear the shock tower. Now I am going a different route.
Still draw through for now.

Scottyd, You are my hero. I quit on my TBI/Turbo/292 because the computer end just kicked my butt. I'd like to know all the details. I built a Megasquirt and it worked but I got lost in the laptop part.

Yours sounds great and I'd like to follow it all the way to the road. Thanks!

Beater, which TBI unit did you use? Im doing an intake for one now and am curious.

Were you doing a draw through TBI or blow through?

I have but 1 question (at this time)... will the tbi enrich enough?

I was using the draw through turbo form an '81 Firebird. The TBI was from an '89 350 with injectors from a Big Block for extra fuel. There is a link to pictures on page 1 of this thread.

Cool. Draw through with 85 or 95lb/hr injectors should be good for 300-320HP or so.

Beater, My setup is using a 16196395 ecm from a mid 90s GM Pickup. Wiring harness from the same. I'm using a Moates ostrich to emulate my chip, and to tune.

Don't let the wiring intimidate you, for the most part if you grab the harness as complete as possible from a donor it only takes 3-4 wires to hook up and make it run. Distributor reference, switched power, constant power, grounds.. A lot of the wires eventually will come out the harness not needed and the ones for sensors will only work in their proper location. Its still good to know whats what and why.

As of now I am using a 4.3 throttle body (same as a 5.7) and 4.3 injectors.. I am just now to the point of data logging so that I can start a tune for actual boost.. the stock 4.3 equipment is a great fit so far for my 250 for normal driving easy not hammer down running. But it will not be enough for 10psi boost

That said there are a few different options for more fuel while keeping it TBI, bigger injectors and an FMU style regulator to raise fuel pressure based on boost reference (supercharger guys seem to like this) A 2 bar map sensor that will allow the computer to see boost in a tuning software (I'm using tunerpro) OR to keep it down and dirty adding an extra injector or fuel solenoid that is actuated by a Hobbs style pressure switch at a preset psi (boost reference)

The only thing about adding bigger injectors that i don't care for is that most likely you'd lose some low end drivabilty and tuning similar to jetting a carb ultra fat.. So i am leaning towards tuning for cruise the BEST that i can using my 4.3 stuff and then supplementing fuel for boost with an extra injector.... lots of possibilities here..

You can even use a nitrous system fuel solenoid to add the fuel and change the solenoid jets out to add or subtract fuel keeping it a little simpler, but i think i will use a cold start injector and have it pulse off the engine along with the other injectors with a boost referenced regulator to raise fuel pressure as boost rises BUT... then again I am still deep in thought about it all!! And i might change my mind tomorrow lol TIMING... is what the computer is really gonna be useful for.. and what is really stressing my nogan.

You could also add a methanol injection system when you are boosted.
I use this one. http://www.alkycontrol.com/

I had to take out fuel in the fueling tables. The Alky control can add a lot of methanol.
I also use Moates, code 59, & Tunerpro RT but not the ostrich, this one http://www.moates.net/apu1-autoprom-package-usb-version-backorder-til-122414-p-54.html?cPath=64

http://www.code59.org/index.php?wwwRedirect

http://tunerpro.net/

MBHD

Great point Hank. I've actually been researching using e85 vs methanol for that purpose.. the consensus on which works better seems mixed. But e85 for less than two bucks a gallon (right now anyways yay!) Seems like the way to go...most definitely is a consideration. I almost sprung for that same moates unit but idk that I'll be burning chips anytime soon and i already had a aldl cable so I went with the cheaper Ostrich.

http://forums.turbobricks.com/showthread.php?t=73061


Here is a great read

In 2008 efi-diy and I did a demo at the Inliners picnic at Bonneville. We used his megasquirt and a TBI and stock harness from an '89 GM van. We put it on the 270 GMC in my '53 Chevy pickup. We had it running in less than an hour. We had a bad vacuum leak under the TBI (no one had a big allen wrench) and the fuel pump kept blowing the cobbled fuel line apart. I ended up with all of that stuff except the MS. So I built one. That's where it sits today. The Idea was to run it on the 270 with no turbo until I learned how to tune it and then switch it to a 292/turbo for my '68 flatbed. I'm into a couple of other projects now but will get back to it someday.
2008 DEMO
TBI DONOR

Pretty cool stuff beater..I really dont know about the megasquirt stuff. I did look into it and my opinion is with a setup as simple as a TBI and for a fuel injection beginner like myself its overkill. There's a lot that can be done with the gm ecm. The one I chose can even be used for multiport fi with a couple of mods... which some day I will do.

Ha! You were part of that?? I've heard the story and it comes up from time to time when ever going to Bonneville or some other car event, about Megasquirt'ing some vehicle out in the field like that.

Tuning for drivability in general isn't very difficult. I can get a vehicle running and driving with megasquirt fairly easily, but I am far from being a maximum performance tuner. I can keep the fuel rich and the timing conservative though =)

A lot of what we had was just temporary for the demo. A small tank with a return line in the bed, a harness with all the wires and a couple of mods, and very iffy throttle set up. We had planned to drive it a little but the vacuum leak and the fuel line coming off ended that. It was very windy and getting dark. My friend Vic and I had never met Marc before. We had planned it here on this site. We prepped the truck from Marc's instructions. The truck was from Nevada and the TBI, harness and MS from Canada. We did get it running. The fun part was putting the carb back on in the dark. Some kind soul loaned us a flashlight or we would have never gotten done. At that point it was Vic, the flashlight guy and me. Everyone else disappeared.
We were actually setting it up this summer so if Marc had time we were going to do a permanent conversion. Maybe next year.

Initial timing, no boost, as much as you can get away with. 12 degrees?
Under boost, 10 PSI, approx 14-20 degrees, like I said before, what ever you can get away with., just do not detonate it.
My estimates are with running 91 minimum octane.

Add Xylene or toluene to get a boost in octane.
http://www.gnttype.org/techarea/misc/octanebooster.html

MBHD

Sounds like a good start for initial tuning.... I will go with the ol less is more mentality until i get this thing further down the road.

Already contemplating a mpfi setup..