Tampa 928s

Murf s-3 kit retrofit issues
85
We installed Murfs Stage-3 kit and it seems to be running very rich. I know the S-4 FPR is much higher so I have an adjustable one set at 50 Lbs with relay bypassed. Now it will just die while at idle or with throttle I can get it restarted but need to hold open the throttle.
The stalling seems to be like the key was turned off. The possible items of interest that were messed with were the fuel pump and Inj relays and the injectors. I ran into this issue a while ago with an injector wire shorting. Seems like two unrelated issues but need to get the richness sorted out I don't believe this would cause the car to stall. At idle it reached 14 or so before it stalled but it was run you out of an open garage rich.
Any feed back?

robot808

Did you try Murphy? The Packers game will be over soon...

Shane

Do you have the donut on the MAF?

Did the kit come with a premapped chipset?

Tampa 928s

Yes he recommended the 50 lbs on his way to the game yes donut and yes chipset!

Tampa 928s

85 S/C
Looking at the manual it shows Fp on pass side with vacuum line attached. My replacement regulator has no vacuum port but the damper does. I remember an error on the manual is this correct set up?
Stock FP is 39 S4 pressure is 55 would I set this back to 39 and not be concerned using the 42 lb injectors in the stage 3 kit?

Shane

As long as you don't hit maxboost for too long a time frame. That is what got my headgasket running the stock pump and stock pressure with 11psi boost. The 42lb injectors can feed a lot of fuel, and keeping all of them fed was why Tim and Mike suggested I change up to an 044 and/or bump the pressure up.

All of my dampers and the reg have vacuum ports, even my adjustable FPR has a vacuum port.

Tampa 928s

I am running about 6 lbs maybe a good idea to replace the FPR with my stock one and see what happens. I am still looking for it I put in a safe place and cannot find the darn thing.
I added the FPR freebie, but it does not have a vacuum port. The strange thing is the Lm-1 shows stoic but getting gassed out of the garage.

Tampa 928s

I was incorrect about the vac line to the FPR changed out to the stock one, replaced FP and Inj relays starts then just shuts off Super charger hose disconnected.

Tampa 928s

Data logger shows inj duty cycle pegged at idle.

John Speake

Almost sounds as though it is running in limp home mode, or your O2 sensor is bad..

Tampa 928s

85 don't believe it has a limp home mode worked fine until we installed the stage 3 kit!

frankle951

Hey, hope you find the issue, Im thinking of buying a supercharger, don't know if Murf or 928Motorsport, is the better bang for the money, with no issue ??????

John Speake

Which means you've learnt something new today :-) Worth double checking the connector...... also try disconnecting the O2 sensor..

rgs944

Yep, every known Red 928 known to man should be Supercharged. If you want the fewest issues I believe in going with a low boost kit. That will give you plenty of usable street power and with good reliablility.

frankle951

Thanks, low boost sound good, less issue, my 86 928S will get the kit.