Adjustable Fuel Pressure Regulator

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Stealth_xr
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Post by Stealth_xr » Tue May 20, 2008 12:25 pm

well for whats its worth. I've got my bbk set at 27psi at idle on the rail MY bbk is advertised 35-70 psi. ITs fuctioning with out problem. Above 35 at idle it breaks up underboost( might be time to amplify the spark) but i'm only running at 12psi boost right now and just getting her running again. I really need to invest in a wideband and an EGT before i start getting deep I'm also running the old stanger cfi 46lbs injectors. I haven't swapped the pump yet( i have one tho ha ha).

Amacar
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Post by Amacar » Tue May 20, 2008 1:52 pm

Jim D,

I have no secrets, I'm just a Newbie trying to learn. My Dyno results (approx, as I don't have the papers with me) are (at the rear wheels):

With 3" exhaust, front mounted intercooler, gutted and rotated upper, ported lower and Forge bov: HP 174, Torque (I'll have to check)

With addition of Walbro, big VAM, PE: HP 208, Torque 215

I still running the stock air box with a K&N filter and an additional cold air inlet. This week I will be swapping in a K&N cone through the fender. Maybe this might help lean it out?

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Stealth_xr
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Post by Stealth_xr » Wed May 21, 2008 7:25 am

I don't think it will help to lean it out. The fpm/fpr will. I don't know about the PE but i do know the LA3 likes to run rich as hell.

aviatorpa23
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Tks for the numbers

Post by aviatorpa23 » Wed May 21, 2008 9:43 am

AMACAR: Tks for the numbers - I'll post the 87 dyno numbers in a month or so, it will not have the gutted intakes or the walbro fuel pump at that time. JD
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jkxr4ti
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Post by jkxr4ti » Wed May 28, 2008 4:51 pm

I was going to try the CFI Regulator route but then i found this on summit's web site:

accel fpr

Its hard to beat that at $58 with the same range as the bbk and kirban.
Merkur....Its German for Mutt....Mustang, Saab, Volvo, Lincoln, Contour, Cummins... and the list goes on.

Jeremy Kemp

1988 XR4Ti Chestnut Brown/Spice Leather
MC2 Coilovers and Bushings, Contour Rims and Rotors, Ported Motorsport Head, Cosworth 4x4 Intercooler, Holset HY35 Turbo, 80LB Injectors, Megasquirt2 EFI

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deathbypsi
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Post by deathbypsi » Thu May 29, 2008 5:29 pm

My $.02

Get a wide band of your own. The single best thing you can buy for your car hands down.Having your a/f ratio off by just 1.0 will make huge power differences. I would not recomend playin with an adjustable fuel reg without being able to see what your a/f is doing. You ever done a headgasket on one of these yet?You might be soon.

In my experiance it is possible to get this tuned in pretty good if you do it right.

If you are at 12.6 at 6k/wot you are too LEAN. You need to raise the fuel pressure to get it back down to around 11.5-11.8 range.
The reason its so rich down low is from the VAM door being sucked open to early,you can help lean it out down low by tightening the vam spring to put more tention on the vam door so it will not open as and so fast before you hit WOT. It will take some playin with but it is totally possible to dial this in way better than it is now.

If raising fuel pressure doesnt richen it up at WOT you could be beyond what the injectors can flow or a possible fuel pump issue.
Brian R.
86 SVO

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