Vlocity

Hi,

I didn't want to further hijack anyone elses injector thread. This sure has been a popular topic this week.

Short version is that I am picking the 36 #, because my model year 85 ecu will not handle the 42# at idle and the 30# that are in there now have to be run at some pretty high pressures.

I have found several sources.

First are the RC Engineering at $78.00 each. I don't know anything about them, they look like they would work.

http://thmotorsports.com/rc_engineer.../i-150536.aspx

Next are Marren Motor Sports, they have a good reputation and I have used them before to balance and clean injectors. The down side is there is no groove for the rail clip. But that would be any easy fix. $49.00

http://www.injector.com/specs/0536.p...92d67e0fdca60c

Last is Lucas injectors ....at about $39 each. Found on Ebay. These have the injector clip slot, but I don't know anything about Lucas.

http://cgi.ebay.com/ebaymotors/8-36l...mZ320205669784

Anyones experience or recommendation would be appreciated.

Thanks,

Ken

Abby Normal

I used my fuel rail as a jig to mark the injectors and grooved them with a dremel tool so the new body style 36# would accommodate the clips. It took about a half hour to do all 8.. I would not run these injectors without using the clips.

I've never used Lucas injectors and was advised not to by a tuner. Some one else said do not use Accel also.

There are also some high performance Ford/Bosch 36# Blue Top injectors. They are the old body style and equipped to handle the standard clips we have on our cars. They're getting harder to find however they are a great injector for the price also.

Leslie 928 S2

Here's one choice.

Accel Injectors

You must use the Porsche O-rings to install.

There are plenty of other choices, but these are known to work.

Leslie 928 S2

Abby, who said not to use Accels? They were prescribed for us originally by Doctor Injector, and are great injectors. They have caused us no trouble whatsoever after two years.

Glenn M

Can the ford F87E-375 white top injectors be used?

http://www.fiveomotorsport.com/Parts...E-DB23lb_8.jpg

Thanks,
Glenn

AO

Ken-

Not sure why you think 42# won't work for you. The 42# Injectors will work on the 85/86 cars. I've seen it first hand. Shane's Murf kit uses 42#. I believe the issue is that there is not a pre-defined 42# injector setting in the Sharktuner S/w for the 85/86 cars, but you can set it custom if you want.

123quattro

All the GM 3.8 supercharged engines used 36# injectors. That could be another good source of some cheap alternatives.

Leslie 928 S2

Hi Glenn, they do fit....however, word to the wise, we had a poor experience with that particular vendor's products. I'd steer clear.

We are on our second set of 36 # Accels, with which we are very happy, and they also have the groove needed for the S4 fuel rail clips.

PorKen

The custom entry allows for a selection from 12.6 to 99.1, in fractional amounts. (This changes the cranking pulsewidth, three code constants, and populates a 9 cell flow lookup table according to coolant temp.)

Not sure why >42# would be a problem? IMO, the LH2² SharkTuner manual is not as well researched as the LH2³. For example, the manual warns to tune the base map for 14.7:1, but this is cut and paste from the 2³ manual. LH2² doesn't learn or remember, so you can tune the whole map for 13.2 (which I did) or whatever you want, and the O2 sensor will pull it lean when cruising.

You can also use the custom rate if you up the fuel pressure. I found I was 100% injector duty after 6200 rpm, so I put in a '87 S4 regulator. Using the calculator below, I put in a SharkTuner equivalent of 29.3#. This was too lean, but 28.7 gave pretty much the same AFRs as before, but now it max'es out at 85% injector duty at 6500rpm and a 13.2 AFR (12.4 = 89%).

http://www.rceng.com/technical.aspx

24lb inj. at 3.8bar/55 psi is equivalent to a 29.3 lb injector at 2.5bar/36psi

AO

BTW, depending on your HP goals the 36# may not be big enough.

At 6300RPM at 9psi, yesterday I logged 80.4% injector duty cycle. Granted I was a bit rich at 11.4 AFR. When I was using the 30#, I was running out of injector quite early. 36# might just make it, but won't leave much room for sure.

Glenn M

Nice calculator link. Looks like 42lb injectors are sized pretty well for 500 crank hp.

Glenn

IcemanG17

http://www.fiveomotorsport.com/Injector_SetsMODS.asp

I bought a set of 19lb stock replacements from these guys...they carry tons of injectors....they have just about everything from stock up to crazy HP....

PorKen

I get 31.27# with a stock S4 fuel pressure?

CHP = 500
#Inj = 8
BSFC = 0.45 (4 valve, 0.5 for 2 valve)
Duty = 0.80
PSI = 55

31.27# @ rated 45PSI/3bar


This is what I'm shooting for with my S3 w/X-pipe + '87 S4 FPR.

CHP = 380
#Inj = 8
BSFC = 0.45
Duty = 0.80
PSI = 55

23.76# @ rated

http://www.rceng.com/technical.aspx

Rick Carter

Porken,
I think that calculator doesn't take into consideration the power needed to run the SC.

PorKen

Doh! Woulda never thought of that.

Glenn was right, at .60 BFSC.

(Hides face in NA shame. )


CHP = 500
#Inj = 8
BSFC = 0.60
Duty = 0.80
PSI = 55

41.69# @ rated