BrianG

Thanks very much Daryl, Mike and Jim. This is coming together nicely. One last fuel system question, if you would.

If you look at Rich's '85 car with the custom fuel rail logs, you will notice that he deleted the fuel dampeners. I plan to use the same logs. What is the consensus on the need for the dampeners?

BrianG

Next issue......... The '86 throttle body I got from 928 Int'l does not have the Closed/WOT switches on it. I'm not sure I can even see where they would mount.

I gather I need them?

Does anyone have a picture of the throttle body with the switches mounted?

It would help to decide what bits I need to order.

heinrich

You need the S4's.

Ketchmi

Uhh Mike, the ARRFPR does indeed decrease fuel pressure...I have run as low as 25psi on the 89' with one. (with 30# injectors of course)

mspiegle

The BEGI2025 unit that 99% of the SUPERMODEL kits use does NOT decrease fuel pressure. IT IS IMPOSSIBLE.

The unit works in tandem with the existing fuel regulators. The ONLY way you can decrease the fuel pressure is to reduce an in-line restriction. Since a restriction is already imposed by the stock regulator - it is physically impossible for the BEGI RRFPR to lower fuel pressure. It can only increase the fuel pressure by adding more in-line restriction.

Please do not confuse people on this thread.

Jim_H

I'll get you one, Brian. I don't think the dampeners are required but hopefully somoene else can chime in to confirm

BrianG

Are you saying that the mounting will be intuitive?

Wanna bet!!

mspiegle

You need the throttle switch from an 85/86 car if you don't want to do any modifications. You may use an S4 switch if you drill a hole through it (VERY carefully) and mount it backwards. The reason is because the throttle opens differently on an S4.

mspiegle

You can only use the S4 switch if you physically modify it to mount backwards on the throttle body.

Jim_H

Thanks for that Mike. I didn't remember use the S4 switch

mspiegle

The fuel dampers are REQUIRED. They are there for a reason. Fuel injector pulses will screw around with the fuel pressure. You may find yourself running lean in certain cylinders if you leave these out. As each injector opens, you get a drop in fuel pressure. The damper eliminates this.

Jim_H

Just get the 85-86 switch.

mspiegle

Just for clarification, regarding fueling requirements for the '87+ cars:

The ONLY kit that may run without 30# injectors for an '87+ car is the basic 4psi stage1 jag/eaton kit. For anything more than that, USE 30# injectors with 85/86 regulators.

CMW

Yep

FlyingDog

Mike, the BEGI is an FMU. An RRFPR will reduce fuel pressure like any fpr. Also, Tony is running 24lb injectors with more than the basic 4psi kit. IIRC, his 30lb injectors wouldn't idle right, but at least one was bad.