350swapped87

I swapped the 305 out of my 87 trans am, I also moved from the tpi to a carburetor. I'm wondering if anyone has wiring diagrams for this kind of set up? I installed a MSD distributor and ignition controller.
is it possible to run this engine without the ECM?

Tuned Performance

iTrader: (92)

You can run without a ecm, but what transmission are you using?
Didn’t the msd come with a schematic?

OrangeBird

iTrader: (1)

I figure I might as well start off by telling you that eliminating the TPI don't get a lot of love around here, so if you get any negative responses at least you'll know why

Now, since it's your car to do with as you wish, time to answer and ask some questions.

Yes of course it's possible to run your engine minus the ECM, cars ran without ECMs for what, 75 years or so before electronics took over? If your carb and ignition are both designed to run without an ECM you should be about 99% of the way there, with the emission controls being the only other engine consideration. I know the EGR is one of the first things people who do carb swaps like to eliminate, again; your car your business, just mentioning it because it was originally run by the ECM. Of more importance is; Does this car have an automatic transmission? If yes, the torque converter clutch (AKA "Lockup" converter) is controlled by the ECM and that will need to be accommodated by a stand alone TCC control kit (Summit Racing & such sell them). Another big consideration is the fuel tank venting VIA the charcoal canister, yet another ECM function that won't work right without the ECM, or some modifications. I think what I'd do there would be to duplicate the system as used on a mid 1970s F body, which purged the canister without using an ECM (it used a "TVS, Thermal Vacuum Switch" and such to get it done). One way or another, you will need to properly address the fuel tank venting/canister purge issue lest ya spend the rest of your days smelling fuel and or dealing with potential fuel starvation issues (common when a carb swap ends up with the canister removed and the vent line deliberately blocked off).

As a bonus, it is frequently asked if the gauges will still work, the good news here being that the ECM is not in control of any of your gauges, just make damned sure to leave the "VSS buffer" in operation lest you loose your speedometer.

So there, you've now got some stuff to think over and investigate, I wish you well on your journey...

OrangeBird

iTrader: (1)

And again, TP beat me to the punch, , while I was typing out my long winded post....

Tuned Performance

iTrader: (92)

lol, I kept the response short to beat you to the punch 🤣

Firechicken82

Gonna need something to control the fuel pump in the tank and IDK if you can make the pump pressure work w a carb or not, I don't do anything w carbs. Now the computer controls the pump. I suppose you can make a switch that controls a relay. I'd just go with one of the modern EFI systems. They work great and are pretty easy to instal.

Tuned Performance

iTrader: (92)

Ops controls fp relay or can rewire the fp relay to accessory power to control it.
but putting back the tpi would be a better choice 😂

vorteciroc

Honestly keeping the TPI System to use on the OP's current Engine would be a mistake.

The GM "Fast Burn" Cylinder Heads being used flow far more than the TPI Manifolds can support.
I have not touched a set of those Cylinder Heads in over 15 Years...
But I used to get a good 550 to 600 HP out of them with 383 to 396 Cubic-Inches.

There are limited Options for Intake Manifolds with a Vortec Bolt Pattern...
And the Best Performing Intake Manifolds use a 4150 Model Carburetor Flange.

The Highest Average HP and Highest Average Torque has been shown to be produced by the Edelbrock "Vortec" Performer RPM Air-Gap Manifold.
I would ideally use this Intake Manifold with some sort of EFI instead of a 4150 Carburetor.

A Four-Barrel Throttle-Body that places the Fuel Injector nozzles in the Base-Plate would be a simple solution for those that do not do any Fabrication...
And still want something that performs decently (compared to a conventional GM TBI Design System).

Port Injection (One Injector in each Intake Runner) with a Four-Barrel Throttle-Body (Injectorless), or an Elbow and a Mono-Blade Throttle-Body would be ideal.

In terms of running the Engine with a Carburetor and Electronic Ignition...
No Electronics are required except for the MSD Components that are being used for the Distributor.

Fueling (Pump and Regulator) can be Mechanical or Electric...
But for NO reason needs to be Electronic.

I try to tell everyone to avoid assembling a "Dead-Head" Design Fuel System...
Go with a Return Style Fuel System, even with a Carburetor.
There is a Return Fuel Line already, from the TPI System.
A Return Style Fuel Pressure Regulator is all that is needed instead of a Standard Fuel Pressure Regulator.

The Fuel Pressure Regulator will be placed in the Fuel System after the Carburetor or Throttle-Body.

Tuned Performance

iTrader: (92)

where did fast burns come into the chat ?