Tuning a TBI pressure regulator?

I have a '95 Chevy Suburban with various engine mods (383 stroker kit, Edelbrock Performer manifold and cam, headers, adjustable pressure regulator) and would like to tune the regulator for the proper mixture. Anyone know the right way to do that?

Thanks.

Reply to
odelrio
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The regulator dictates rail pressure to the injectors, do not change the rail pressure in a attempt to change the air/fuel mixture. Raising the rail pressure causes the injectors to draw more current to function correctly and this will cause the injector drivers located in the ECU to fail. the air/fuel mixture is adjusted by increasing/decreasing the dwell and duty cycle of the injector and this can only be done by replacing the PROM chip in the stock ECU. You have several options including replacing the factory ECU with a aftermarket unit which allows you set up the entire fuel curve and the ignition advance curve as well using a laptop computer. some people are even selling a replacement ECU that you build yourself for under $200.oo and it is fully adjustable while you are driving the vehicle. Your first step should be installing a air/fuel ratio monitor (i use a MSD unit) to see if the mixture is rich or lean at different rpm's and engine loads, then you can determine just how much damn money you wanna spend on that thing ............LOL The MSD unit allows you to install 2 heated sensors and check both banks of the engine. fuel injection is cool and i almost took the plunge for a complete MPFI retrofit setup but i'm making more power with the carb.

Reply to
Mad Dog

Here is some links for ya,

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i like the Megasquirt system......

Reply to
Mad Dog

Ah, got it. So my main concern was not having enough pressure and running too lean. If the computer takes care of the mixture, then I'm okay with leaving it stock for now. So I guess the question then becomes, since the pressure regulator is adjustable, what should it be set to initially and what should prompt me to increase or decrease it?

Thanks again.

Reply to
odelrio

I'm sorry for taking so long to read the reply, raising the rail pressure will fatten the mixture because more fuel will be pushed out the injector when it's open. Try reading the plugs after a WOT run and then increase the rail pressure a little at a time until the plugs darken up to a light brown. i use a Halmeter AF-30 for air/fuel mixture calibration.....pricey but very accurate.

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-- Mad Dog

Sorry 4 invading the e-mail but i did'nt know if you still had access to the message on the server.

Reply to
Mad Dog

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