1970 pontiac 400

[Irishbmx]

Ok I've been reading threw alot of the stuff and am interested to see if I can make this work.
The engine is a Pontiac 400 same bore/stroke as a sbc 400 but completely different engine I am planning on making my own throttle body intake with fuel rails based closely to the LT1, I am also planning on throwing a turbo on the engine.
So my basic question is will one of these systems work for me, which one, what else would I need, and what problem might I run into?
If anyone's built a similar system could you provide me with details or links? Any information is appreciated.

[Matt Cramer]

Sure, you can get this working; I did a conversion on an engine that was never EFI myself (Chrysler slant six). The biggest questions to determine what ECU you need:

1. What would you like to run for ignition?
2. Are you going to use a PWM or stepper idle air control valve?
3. Any special features you need the ECU to do besides fuel and spark?

[Irishbmx]

Sure, you can get this working; I did a conversion on an engine that was never EFI myself (Chrysler slant six). The biggest questions to determine what ECU you need:

1. What would you like to run for ignition?
2. Are you going to use a PWM or stepper idle air control valve?
3. Any special features you need the ECU to do besides fuel and spark?

I'm not sure on the ignition or the idle air control (but I do wanna do one)suppose I will have to research it more unless someone has advice on it.
as far as other features just the ability for the turbos besides fuel and spark and hopefully timing, I am very new to this have never tryd anything like it.

[Bernard Fife]

Irishbmx,

The simplest option may be to adapt a GM 7-pin HEI distributor (like this: http://www.megamanual.com/ms2/GM_7pinHEI.htm). You might have to find a 400 Pontiac 4-pin HEI distributor and modify it to fit the 7 pin module (the 7-pin module has a slightly different bolt pattern and different connectors than the 4-pin, but it is likely possible to swap them).

The best option might be to adapt the Ford EDIS system (http://www.megamanual.com/ms2/EDIS.htm) with a crank wheel, module and coils. This will involve some fabrication for the crank wheel and sensor, though. There are a number of people selling EDIS system on eBay, etc.

On my 406 Chevy, I have a 900cfm Holley 4bbl TBI unit as a throttle (but used with port injection), this comes with a GM style stepper IAC (http://www.megamanual.com/ms2/IAC.htm#stepper), and bolts onto a standard 4bbl manifold, so it's pretty handy. But there are quite a few PWM valves out there too (the ones used on the Ford's with TFI/EDIS seem the most common, and may be adaptable to more situations than the GM unit).

Lance.

[Irishbmx]

thanx lance that will help me with the research, I was also thinking I could buy just the distributor from the eddlebrock efi kit and maybe use it? Not sure if that would work.

[Bernard Fife]

Irishbmx,

That distributor should work. You will want to find out everything you can about it. Most of what you will need to know you will be able to figure out by looking. For example, is it 8 tooth, or more, and is it a VR sensor (2-wire), Hall sensor (3 wire), or optical sensor, and does it have an ignition module or does the ECU control the spark.

It may very well be based on a 7-pin HEI module (8 teeth, VR sensor, internal module), as these are common, cheap, and known to work well in aftermarket applications.

Lance.

[8974Ollie]

HI, Irish BMX

I too am building a MegaSquirt controlled EFI for a traditional Pontiac engine, how ever it will not be a turbo engine. I have a 455 going in a 79 TA. I am using the Edelbrock Victor EFI manifold with an Accufab Throttle body to retain the shaker scoop on the TA. Save your money don't get that Fancy EFI distributor, A stock HEI can be made to work. As Lance indicated it is very easy to adapt a wasted spark EDIS ignition. If you need a 36-1 trigger wheel I have some for the Pontiac harmonic balancer. For my ignition I will be using the EDIS control Module and COP.

[8974Ollie]

This is a link to Performance Years board, discussing EFI and Pontiac engines.
http://forums.performanceyears.com/foru ... hlight=COP

[Irishbmx]

Awesome thanx Ollie! I hope that guy gets that set up working cause that's what I was planning to do turn a pontiac into a beefy cracked out ls1 only I am making the intake with a forward facing throttle body to.

[krisr]

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