SMTCapeCod

That's it, thanks!
And the other one I cited is listed Here

Products-> UTCIS-> UTCIS-PT

Imo000

It only becomes a problem if you constantly keep constantly revving or keeping the engine near redline. Since these smaller turbos will run out of steam before the redline it will keep him form taking the rpms too high anyways.

I’ve helped a buddy install a turbo on his NX2000 (turbo system came off 1st gen Ford Probe GT) and the turbo is a little smaller than what the engine needs so it runs out of steam 1000rpms before redline. We could notice this when looking at the tach, otherwise you become used to it and naturally don’t rev it past the peak. This car, with the home build turbo system, is still very strong for a 4cyl. Good enough to run 13sec in the ¼ mile.


These turbos that are going to be used, are off a 2.2L Mazda engine or off a Chrysler?

Fabio421

But why intentionaly use undersized turbo's. From his post it seems that he hasn't bought them yet. I was just adding some insight so that he is a better informed shopper.

Imo000

I think it comes down to cost. If these turbos are OEM, from a regular production car, then they can be found used for next to nothing (~$100 or less). This is a budget buil, just like mine was, and if he you can get the entire system built for under $1500 it will be a very cost effective project. Look at it this way, he can get 80% of the performance for fraction of the of a custom turbo system. I’ve built my SC system for under $1000 that produces around 400FWHP. Sure there are others with stronger, nicer, faster setups than min, but I haven’t seen anyone that was cheaper!

michael j wright

Terra in your firdt post you were saying that all cis systems use lambda controll- they don't - my 82 euro has K-basic wich means no lambda - no o2 senssor and no ecu. you can check yours to see if it has o2 sensor or a valve near the fuel dist that looks like a electronic injector - wich is actually the lambda controll- if these are missing the chances are you have K-basic. Have fun with the project!

SharkSkin

That's right -- There are CIS variants, K-jet(like mine & Micheals) and K-Lambda which has a Lambda circuit added -- sometimes during the federalization process, sometimes for other reasons.

dr bob

I did a bunch of mods to my Saab turbo, CIS with the lambda system. Ended up building a "brain" from scratch when the old one died. Original was all analog stuff, BTW. Barely north of something you could build with Radio Shack parts. But the opportunity was there so a breadboard version then a finished went in. There is a lot of tunability in that analog system, since the control pressure can then be easily adjusted for various conditions... like LOTS of boost. Had no trouble upgrading the turbo and wastegate to make 325 wheel horsepower comfortably with the improved engine management. Relatively cheap too.

I would stay away from messing with the airflow measurement stuff. As much as we think the swinging-pancake and the barn-door flow sensors are "bad", they aren't. The hot-wire sensors do the mass corrections for you, the MAP systems take a lot of effort to get just right, and both really need a digital brain. Meanwhile, the baisc CIS 'sensor' just needs to stay clean and be driven regularly to keep it functioning as designed.

The Saab warm-up regulator was offered in an altitude-compensating version that made mixture bias under boost quite simple. Might be worth searching for one of those. It cured about half of the high-boost lean conditions on its own.

I also changed out the fuel pump to a higher-pressure unit. I still have a new spare in the box, sitting on the shelf in the garage if you need it. Yours for postage. It's the in-tank pump, don't know how that will work on the early 928 as far as fitment but it flows plenty enough for 400+ HP. PM me for part number if you need it.


I had a home in the Sierras at Mammoth Lakes, and regularly made that 347 mile trip in less than 4 hours very early in the morning. Leave OC at 4am, in line with skis on when the first chair opened at 8. Only one episode with enforcement, when the cruiser couldn't go 135 up the grade on 395 north of Bishop to keep up... Blew up a cop car, $75 ticket, GREAT day of skiing. Not so immortal these days though. ;(

RicerSchnitzzle

I read on K-jet.org that the CIS came with the ECU, however I made the mistake of assuming ALL CIS came with the ECU. My car has no brain or O2 sensor, no Lambda when federalized, yet has CIS. Makes life easy, as I can make manual adjustment a little at a time untill fuel needs are met. And they are basically free. Not going to do any valve body mods unless still lean after other easy fixes are done.

I would like to upgrade my fuel lines. Does anyone know the thread and pitch for the CIS and Injector fittings?

Line's I'll be using are standard 3AN, so I would need a 90* adaptor from 3AN to the DIN threading. (Some NPT are clse enough to DIN to work) Would end up looking like the 928MS upgraded fuel lines. Premade braided lines with fittings are $15 to $20 each. With 8 to buy it will be under $200. With another $50 for adaptors, it should look nice and be very functional with an improvement in ID. Not as nice as the 928MS drag car lines, but still more than needed on the 928. It will also match the lines for the nitrous except they are slightly larger at 4AN.

michael j wright

Terra, I would highly recomend this book -you can get it at 928int