7th Injector Setup

[SGO930]

Hey guys. Looking to see if anyone can identify a source for a 7th Injector Setup or may have a complete setup that they had removed from their car. Interested in acquiring this for a project I'm working on.

Thanks.

[RarlyL8]

7th injectors are a bad idea. The fuel is not distributed properly to the cylinders causing some to be leaner than others. I suppose if you just dump a bunch of fuel in the engine may not get hurt but it is not optimal.

[smurfbus]

I have that cold start injector behind a button just for testing purposes or limp home mode for air leaks.

[SGO930]

Have heard that same concern. Not sure how this will ultimately play out with the project but still interested in locating one if anyone has any leads. Thanks again

[copbait73]

Yes, I have the Miller-Woods Controller called TurboGroup Fueler. Sold and used on many boosted Porsches in the late 80s and early 90s.

Fuel distribution can be a problem however everyone running a flat 3.0, 3.3 TURBO or 3.2 N.A. has the same problem with dry air distribution so they are just whistling past a graveyard to think otherwise. Unless one does an EGT survey and adjusts each individual injector's fuel flow they have mixture/distribution issues also....it's the nature of production manifolds. Use ITBs and the problem may be limited unless the inlet manifolds from the CAC isn 't perfect.

I know one high volume V8 Diesel engine which finally got a different injector in one hole three years after the start of the run to fix a similar air distribution issue.

I run a 7th injector on my 2.4L CIS turbo. PM me on my Fueler box.

[Tippy]

Yes, I have the Miller-Woods Controller called TurboGroup Fueler. Sold and used on many boosted Porsches in the late 80s and early 90s.



Fuel distribution can be a problem however everyone running a flat 3.0, 3.3 TURBO or 3.2 N.A. has the same problem with dry air distribution so they are just whistling past a graveyard to think otherwise. Unless one does an EGT survey and adjusts each individual injector's fuel flow they have mixture/distribution issues also....it's the nature of production manifolds. Use ITBs and the problem may be limited unless the inlet manifolds from the CAC isn 't perfect.



I know one high volume V8 Diesel engine which finally got a different injector in one hole three years after the start of the run to fix a similar air distribution issue.



I run a 7th injector on my 2.4L CIS turbo. PM me on my Fueler box.

Ditto.

Was quite shocked when a couple of Pelicanites posted airflow variances on the Carrera 3.2 intake.

Huge % swings from runner to runner. Not comforting when I tune for boost knowing I probably have a cylinder in the 13's.

[copbait73]

I hope I did not sound argumentative with Brian. That was not meant.
He and I have talked of the need to do EGT and CHT measurements on these engines for this reason. I have an aircraft 6 cylinder EGT for this work.

On a related note a long time local Porsche mechanic has a dyno and has done extensive work to equalize CHTs. Unfortunately he is a bit of a curmudgeon and is holding his findings very close.

[Tippy]

I hope I did not sound argumentative with Brian. That was not meant.

He and I have talked of the need to do EGT and CHT measurements on these engines for this reason. I have an aircraft 6 cylinder EGT for this work.



On a related note a long time local Porsche mechanic has a dyno and has done extensive work to equalize CHTs. Unfortunately he is a bit of a curmudgeon and is holding his findings very close.

MegaSquirt Pro has capabilities of individual cylinder fuel + timing control.

[RarlyL8]

No argument detected just another point of view, which is good.
It's all relative, these engines can live in stock form for 100K miles before a rebuild so there is enough cushion built into the per-cylinder fueling. It's the mods and boost that make me nervous about the 7th injector. If you haven't balance your AFRs or EGTs between cylinders by adjusting the fuel head then you are adding another layer of un-tuned fueling to the mix. The important part is to know what's going on with your engine when adding power.

[copbait73]

Originally Posted by Tippy

MegaSquirt Pro has capabilities of individual cylinder fuel + timing control.

Better yet, the single feature making modern production engines of high power density possible is knock detection, sorely missing to most of us. As much as we love our air-cooled engines they are dinosaurs. Even Porsche abandoned their continued development 20 years ago.

[Tippy]

Yep. I held off due to a lot of talk of false readings due to the inherent noises the air-cooled engine makes.

Believe this thought is slowly diminishing as more and more folks are using it.

[kenikh]

DFI is a magic bullet that just wasn't ready in time to save these motors.

[Ronnie's.930]

Originally Posted by kenikh

DFI is a magic bullet that just wasn't ready in time to save these motors.

I've always wondered "why not" considering direct fuel injection has been used for many decades in diesel engines and so forth (aka - hardly "new" technology).

[wjfk32]

Yes-I have a 7th injector set-up 911SC. Old School HKS-Set-up.. It has worked for me.. Alex/930 and others who have seen my car run are in 911 tech forums know it goes pretty good ..Engine has approx., 30,000 Plus miles.. Currently the engine is out due to a broken head stud.. I have 7006-MSD-6AL-& Epoxy coil-1bar spring-Andial Intercooler-SCsport cams- 915-KEP lightweight clutch pkg-AFR gauge-blah-blah--.. Plummed in the intercooler...as you can see.. Should go with Meth instead..Oh-well
Have done a roll on (Mex) with a lot of bad ass cars.. Last was a 991 turbo walked me in 4th..not that bad...