jrogers

Hello Rennlisters,

I did some searching, and really cannot find a clear answer, so I am looking for some opinions on how to proceed. I have an 87 930 that I have had for 10 years or so. It has around 90K miles, and currently works well. It currently has the following mods:

3.4l P&C
CIS
Euro fuel injectors
B&B exhaust
Tial Wastegate
K27HF turbo
1 bar spring
High flow air cleaner (can’t recall the product name)
Probably 2K miles on rebuild
Dyno’ed at 397RWHP
Good AF ratio, but rich at idle

I am considering putting some dollars into the motor this winter, and I am looking for some guidance. I would like as much power as is reasonable for the cost (maybe 10 - 15K budget), but is still reliable. I would like more low end power, and it bugs me how rich it is at low revs right now. Reliability and drivability is important to me, that is why I have stuck with CIS up to this point. Should I go to EFI, or are there other well developed mods that would allow me more and reliable power?

Mark Houghton

You've already got a nice build! For the money you've budgetted, I would put 964 cams and appropriate valve springs in there, convert to EFI, put a set of headers on, and dual plug it. And you may want to consider flame ringing the cylinders to hold that boost in, and going with ARP or Raceware engine studs and rod bolts to hold everything together. Oh...and meth injection so you can safely run 1.0 bar (or even more).

Disclaimer: I have done none of these mods. With what meager funds I have at my disposal and the parts I already have on the shelf, I will most likely call it good when I add the SC cams and DIWUR to my build.

Mark H.
1987 930, LSD, B&B shortneck Intercooler, K27 7006 turbo, Tial WG, Kennedy Stage 1 PP, HKS boost controller to 1.0bar, Boost recirc manifold delete, BL adjustable WUR w/boost enrichment delay, LC-1 AFR and G3 analog gauge, Greddy boost gauge, MSD6AL and 8762 boost retard ignition, K&N cone air intake, Fabspeed dual outlet muffler

RarlyL8

I'm going to guess that your fuel head has been adjusted for more flow but the WUR was not matched to it or to your fueling needs. This would solve the rich idle issue.
For $15K you can go EFI but that's about it. I wouldn't do it unless you have a known proven competent tuner that will support the system or you can do it yourself.

jrogers

Thanks for the info. I don't think I did anything to the WUR. I do have a euro fuel head, but I don't know that I ever heard about a different WUR. Can you give me more details on this or a source for it. I think I went with SC cams as well for better bottom end, although I remember pondering the 964 cams. I also have a B&B larger intercooler. The details are slowly coming back to me.

What is the best EFI product out for the 930 these days? I would like to do some research on this to see how reasonable the product is to work with for a do it yourself type project.

CaptainCalf

Jim, I'm building an 87 930 now and plan to go EFI with a Carrera intake manifold. My heads & cylinders are at the machine shop receiving fire rings now and the head's intake ports have been bored out to 40mm to match the Carrera intake runners. I haven't decided on an ECU yet, but there seems to be a lot of folks around who have used and like Motec. However, Rarly8 is right. Find a successful tuner and go with the system he recommends and stands behind...

Good luck with it and show us some pics when you get a chance...RC

Strygaldwir

Did you do anything with your compression? I'd give that a slight boost as well as twin plugging and corresponding timing change. EFI is great, but when all is said and done, might eclipse the budget, unless you intend to do a whole lot of it yourself. You might also consider Electronic Ignition. Tends to be more reliable and easier to tune.