Boost Indexed Fuel Regulator

hombre

Nitrous
Joined
Dec 31, 2006
Messages
1,021
We've tuned my IC SC R3 to .82 lambda (12 AF) to give a bit of cushion against detonation at max boost of 14 PSI (7000 RPM). IMO, by using a boost controlled fuel pressure regulator, we can lean that out to the 12.5 - 12.8 range which will result in slightly more power.

Modern boost indexed regulators (FMUs) can maintain true 1:1 pressure at idle (where my SC boost is zero) but are completely adjustable in their pressure curve to give as much as 12:1 fuel pressure at max boost. Another upgrade for FA R3s. :D
 

R34ME

.060 Over
Joined
Aug 5, 2006
Messages
197
Nice piece of kit hombre pig9r my understanding is the IC kit comes with 255 ltrph pump and larger injectors, i already have a walbro GSS342 in my tank, injectors to follow. I am sure hombre will enlighten us......
 
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hombre

Nitrous
Thread starter
Joined
Dec 31, 2006
Messages
1,021
Did you have to replace the stock fuel pump?

Nice piece of kit hombre pig9r my understanding is the IC kit comes with 255 ltrph pump and larger injectors, i already have a walbro GSS342 in my tank, injectors to follow. I am sure hombre will enlighten us......

For FA apps, I highly recommend replacing the stock fuel pump with the Walbro 342. It does not come with the TTS SC kit, but is now recommended by them for the IC SC. You simply cannot tune this level of boost without a higher volume pump. The stock pump just can't supply the huge increase in fuel needed at higher RPMs. The beauty of the Walbro 342 is that it's a perfect "drop-in" replacement for the stock fuel pump. It's also twice as loud as stock when you turn the key... a nice "in your face" clue that this ain't your momma's R3 anymore. :D

I was so impressed with the performance difference that the larger volume pump made, that I began exploring these FMUs (boost indexed regulators) as well. This one is not submersible, and the stock regulator will have to be removed from the system (in the tank). You need to be able to adjust the boost/fuel curve on the FMU so it must be located outside the tank. I'll keep you updated on my choice and installation.

ps. R34ME, remember to upgrade your MAP sensor with your turbo installation (see other thread).
 
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