EFI DIZZY DOES WORK WITH CARB! Now I have 2 much fuel pressure

[whiteponygt98]

Yup, that's right. You read it. The only part of the fuel injection wiring that I removed was the complete injector harness. I left the stock dizzy and pulled the spout. It started right up. Now I have a new problem. I have a malory return style regulator and I can't get the fuel pressure lower than 10psi at idle. Even with the set screw removed completely??? Any ideas? I think i'll just go ahead and order a holley red.
Brent

 

[QDRHRSE]

Wow. I never knew. Does that mean that you left the computer plugged in? All emissions stuff like O2 sensors still connected? The distributor advances and everything???

 

[whiteponygt98]

Everything is plugged in except the spout for the timing advance. It is pulled so that the timing is locked out. I shouldtry putting it in and see if it advances right, but i have to figure out this fuel pressure thing first.
Brent

 

[jrichker]

Sure it will work, BUT you have no spark advance and are locked at whatever advance you set the last time you installed the distributor.

The computer uses the signals from the MAF, TPS, ECT, ACT, & MAP/Baro to determine spark advance. Now with no MAF or TPS, it thinks you are at idle, or in limp mode. If you car was speed density, there is even less data for the computer to work with, it depended on the TPS and engine RPM to set spark advance.

Some education on EFI is in order here. Here's a book that will get you started with how the Ford electronic engine control or "computer" works.

Ford Fuel Injection & Electronic Engine Control 1988-1993 by Charles Probst :ISBN 0-8376-0301-3.

It's about $20 from Borders.com see http://www.amazon.com/ . Select boo...very good, and I found it to be very helpful.

 

[matty50racer]

I am using a Walbro 155 pump and Mallory regulator and can't get my fuel pressure any lower than 11 pounds at idle but it does drop to about 9 pounds when I am on the gas and haven't had any problems with it like that. Unless your floats are sticking at 10 pounds than I wouldn't worry about the fuel pressure.

 

[Js5ohLX]

Sure it will work, BUT you have no spark advance and are locked at whatever advance you set the last time you installed the distributor.

The computer uses the signals from the MAF, TPS, ECT, ACT, & MAP/Baro to determine spark advance. Now with no MAF or TPS, it thinks you are at idle, or in limp mode. If you car was speed density, there is even less data for the computer to work with, it depended on the TPS and engine RPM to set spark advance.

So, in theory, you could hook up a tps to the carb linkage, and since it is sd, just hook the rest of the sensors up, and you would still have a timing curve. Even if it was mass air, you could probably pipe up a sensor to an air cleaner and go that way, it wouldn't be 100% accurate, but I think the maf is only really picky for the fuel curve. I think that is a pretty cool idea.

 

[Michael Yount]

Richker's right - the computer controls advance; without it, the only way to make the efi dizzy work is to lock in the timing at one setting. If it's a racer, that'll work. If it's a street car, it ain't gonna be too nice. And the computer bases more than just fuel calcs on the maf and tps readings. Without them, even if you used the computer for timing, it would make bad timing decisions. If this is a street car, you really need to get a dizzy with mechanical advance, or a stand alone electronic unit to control timing with (MSD, etc.)

 

[88306stang]

my car is converted to carb and i on;ly run 61/2 fuel presure i have the holley red pump and holley regulator with 1/2 fuel line and have never had any problems also put a sump in the tank

 

[whiteponygt98]

I know I will have no advance. The timing is set at 30 degrees locked out. But, this is not a problem. My buddy has a 360 duster and it is a street car with the timing locked out with no problems. This is mostly a drag car but does see some street time. I'm going to leave it like this and see how it performs at the track. I'm not the only person not running a timing advance am I??

 

[89lxcoupe]

you need to lock your timing to at least 35 - 38 depending on your setup i ran 38 with ported 289 heads and stage 1 cam and 650 dp !

 

[Ray III]

If you car was speed density, there is even less data for the computer to work with, it depended on the TPS and engine RPM to set spark advance.

I don't think this is correct; the engine will run with the TPS unhooked. Fuel and timing is determined by manifold air pressure and engine RPM (hence "speed density"). The TPS tells the computer when a change is occuring, so it can immediately compensate instead of waiting to pick it up through the other sensors.

Back to the original topic... don't jimmy rig the thing just because you can. Rip out ALL of that EFI crap and get an MSD ignition.

 

[jrichker]

See http://www.cranecams.com/?show=promo&id=17&PHPSESSID=c1c68e849abba706c6334c7f83e326ee to fix your problem the right way.