strudel

What I have: '79 930, twin plug, Andial intercooler & fuel enrichment, stock heat exchangers, DP muffler, K27 turbo, Tial 46mm waste gate, gruppe b cams (?). I have Euro heat exchangers I will be putting on. The p/o put in a new/rebuilt fuel head, injectors & fuel accumulator. I would appreciate opinions and suggestions on the following items:
compression test: 130-140.
the a/f under idle and normal driving is 11.5-12.0/1.
I did 3 pulls from 2500-6500, went from 11.5 to 13.5 at the top end.
full boost at 3800-4000 rpm.
hot start problem from being flooded. A temporary fix was to shut off the fuel pumps when starting then turn them on after it started.
I'll do a leak down when I pull the motor. I don't plan on tracking the car and would be happy with 370-400 hp.

Is the rich a/f caused by the Andial unit? What's the fix.
How do I get full boost earlier?
Any opinions on the hot start problem?

Thanks,
Harold

jhunt@huntinter

Is the fuel head still black? If so you do not need the Andial for those HP numbers.

nathanUK '81 930 G50

Sounds like you need a modified fuel head from Imagine Auto. Probably the reason for running lean in the higher RPM is that you have the andial fuel enrichment over compensating at the lower rpm when on boost. What was the AFR on full boost at say 3500rpm and say 6000rpm ?

Earlier full boost is helped by using the GHL or B&B type headers.
Also a Imagine Auto S type K27 turbo will come on boost earlier, 300rpm I was told than a non S K27.

strudel

jhunt: yes the fuel head is black.

nathan: I didn't get full boost until 3800-4000, a/f was 12-12.5, at 6,000 and above it was 13.2-13.7.

nathanUK '81 930 G50

You could turn up the andial and see if your above 6000rpm AFR moves with the 4000rpm AFR. If you get lots more fuel at 4000 and very little more at 6000 it would seem you need a modifed fuel head as you are out of flow.

I bought a USA modded head, Stephen says they flow better than a modded euro head & I can keep my stock part in a box.

You could always buy a second hand USA head and then send him it for the rebuild with modification.

Was your power target at the wheels or crank ?

strudel

I'd like mininum 350 at the wheels.
It seems like I need to address the too rich at idle/normal driving (which would explain the louisy gas milage) and the lean high end.

senna21

I'd think with a Euro head and enrichment he'd be fine at higher RPM. Maybe the Andail isn't functioning properly.

I was under the impression from Bruce Anderson's book that the Euro exhaust manifold/headers was much better than the U.S. and about as good as any aftermarket header system.

jhunt@huntinter

Not if he has the stock US "79 exhaust. It is the worst of the bunch.

The fuel head should be fine without the Andial enrichment for the HP numbers he wants.

JBL930

I believe that even the euro headers are inefficient, they are too long and that's why the turbo spools up so slowly, the shorter B&B or 9m headers are shorter and therefore increase the velocity or something, they were using the only decent turbo available back then too which is just awful by today’s standards, I believe the 3LDZ originally came off a ship engine , and to make real use of an up to date turbo you need up to date headers to match. I'm not a mechanic remember so don't tear me to shreds

Chet 930

I had the same fuel head and Andial on my 77 930. Question........how much boost are you running? Whats the CO at idle? It sounds like your fuel system is set to compensate boosted conditions at the sake of practicality for the street. The set up you have should be more than enough for what you are looking for without having to shut fuel pumps off etc. How it even starts without the fuel pumps on even for a few seconds is interesting. The injectors need a certain amount of pressure to open and you would have to have fuel past the injectors for the motor to start. Could it be a bad cold start valve?

strudel

I went with the euro exhaust to retain heat.
DP muffler has a 3 7/8" inlet & 3 1/4" single exhaust, pretty free flowing.
Boost is Tial .08 spring, but goes to 1.0 according to the boost gauge
A/F is 11.5 @ idle according to the LM-1, no c/o info
If the motor doesn't start the first few times I turn off the pumps (switch on dash). As soon as the motor starts I turn the pumps back on. The motor will run a few seconds with the pumps off.
Didn't know if the hot start problem is related to the WUR or cold start valve.
I was going to have the WUR rebuilt. Not sure if I need the modified fuel head. Also not sure if the Andial enrichment is working. I switched it form minimum to maximum while driving and didn't see any noticable changes in the a/f (LM-1)

nathanUK '81 930 G50

JBL is right about the headers, the euro still suck compared to the shorter design like the GHL's, B&B etc. But with stainless steel the heater output will be reduced compared to the stock euro's.
370bhp at the wheels is a lot more than the stock euro 300bhp at the crank, I'm sure the car will run fine without the fuel head mod but you will get a much better fuel curve with the modded head. the andial will cause more fuel to be injected whenever the car is on boost and does not sense rpm at all.
Of course CIS will never be as accurate as going EFI and getting a totally flat fuel curve is impossible.
For me EFI is just way too expensive, I just want to be safe when on boost so the fuel head mod is a compromise.

strudel

Sounds like removing the Andial unit and getting the fuel head mods is the way to go. Yes, the EFI would be nice, but too much money.

JBL930

You still get heat with the aftermarket headers, it might not be as hot as stock but believe me if I have the heat on full in my car it dries my eyes!! Those headers are holding you back my friend, they are totally inefficient for the power and response you want!

nathanUK '81 930 G50

JBL,
I was wondering how much of a difference the SS headers would make, are your stainless steel ?

Strudel,
Don't remove the Andial until you are happy with everything, you can turn it off on that adjustment ****.
When you are happy you could put it on ebay

I see in another post you are going to get your WUR rebuilt, I would get it made adjustable at the same time, a guy on here called Brian can do this for you.