hybred

been reading up a little on the cis system. i have a 80 euro m28/11 and plan on a rear mount set up. the boost i'm familliar with as this will be my 3rd custom turbo build. the cis i'm not. i'm also not looking to make a 10sec. car here. but would like to see 400rwhp out of it. i was planning on swapping out the euro set up for a us intake and throttle body, upgrading to larger injectors and boost ref. regulator with larger pump. running the whole mess on megasquirt. i did a search on the subject and found that it is possible to obtain the power i want out of the cis. anyone care to share some insight on what can be done to the cis?

kary4th

I bought a book by Bosch on CIS a while back. It's very interesting. I found it on eBay for around $15. I'll get you the title, if you're interested.

tammons

First thing I would suggest is ditch the CIS system and get and aftermarket EFI you can tune.
Beyond that you at least need to up the fuel and retard the spark under boost.

They do make a boost retard unit that would work.

You could trick out the cold start injector, but it would be tough to control the fuel from that.

You could try a rising rate FP reg.

You could also add a couple of injectors that only operarte on boost with a seperate controller.

I gave up trying to turbo the CIS system. Dont forget to add some S4 brakes.

Imo000

Just a word of caution, the 928 ignition system has something that for some reason fries the boost retard MSD boxes. While getting exact instructions from MSD, Mark Anderson toasted two of them .
I have two sitting on the shelf casue I don't want to risk frying them.

Airflite40

I have heard that the Euro engines are not good candidates for turbo due to their high compression (10:1)

Also, I dont think that 400rwhp will get you a 10 sec car in a 928. Arent 10 sec supras like 700hp??

tammons

All the better reason to go EFI.

I can talk from experience since i ran one TT car for about 2 months without spark control, you need it. To dodge problems without spark control you have to retard the ignition which kills off boost performance and gas milage. The 928 spark curve is too conservative and really needs more initial advance anyway. I had my last turbo car set up with an aggresive spark curve off boost and it really wakes the car up, helps the turbo spool up faster etc..

SMTCapeCod

Or you could just switch to an MSD ignition running at the full 12V instead of OEM 6V...
Hybred, you can look at my install if the need arises.

As for spark, M21Sniper claims 50 degrees or so, but I think he's also at 8:1 compression.

Aside from the stuff you're trying to swap, bear in mind that I"m a happy dumping ground for spare CIS (and other) parts you dispense with.... You'll probably want thisat some point too: Fuel Injector specs

SMTCapeCod

By the way...if you want to get really creative, someone some time ago fitted a corvette throttle body/Maf (I think) to the front of the 928 intake plenum...

First post of the thread is here:
https://rennlist.com/forums/showpost...30&postcount=1
(More for nostalgia than anything else- not recommending).

hacker-pschorr

I'll have to agree with this - unless your plan is to gut the car down to sub 2,500 pounds. Not even sure 400hp + 2,500lbs would hit in the 10's.

sublimate

His original post said:

hybred

thanks sublimeate... allready have a 10sec. car it won't go around corners well tho lol... i guess i'll wind up going with the megasquirt after all. after thinking more about it, it's just an all around better idea. i've set up two turbo cars. the first with blowthrew carb and the second with megasquirt so i'm familliar with the set up. it controlls spark and fuel. tammons, thanks for the insight as well. i also thought about running an extra injector (s) on a hobbs switch to come on a set point under a set boost but don't know where i would put it. i wouldn't want to try to run fuel threw the intake that was designed to flow air only. think that's asking for trouble. i agree. think megasquirt (stand alone) is the best option to do it right. the last thing i want to skimp on is fuel Airflight40, yes 10-1 is kind of high for boost but it really depends on how well the combustion chamber works. for instance imports work well on higher compression as their combustion chambers are more efficient than say... my mustang i just built. there is also one universal band aid to fight detonation..... alcohol/water injection. it's going to be my best friend. don't think i'll have many problems as long as i keep the intake charge cool.
smt, with going the megasquirt route i'd be using msd. probably a 6al again. wish i could find the extra coin to go with the 7 series looking forward to having you stop by thanks guys for all the help out. i guess there's no such thing as a free luch eh? stand alone it is...

Lance J

Get the 12v mds coil. and call Chris @ turbokraft and order a $625 digital Wur that is Map based. so you can tune it on a dyno. they will be up grading to WBO2 pretty soon. that will get you as close as you can get with out ripping out the cis and going the 3k plus route of EFI.

Lance J

If you wanna go the efi route and save some money. Buy all the l-jet fuel crap, get 85 nissan injectors or 914 d-jet injectors which larger than the stock l-jet injectors. for the ecu buy a "749" out of a 90-93 pontiac sunbird turbo or gmc cyclone or typhoon turbo truck. Email bill Shaw he can order and mount in your new ohm resistor and injector drivers so the ecu can run 8 cylinders. Download the Freescan software for free (data logging) , and TunerPro for free (tuning) . Buy a Motes Chip, wire everything up. Your gonna need a GM TB. because it has a TPS and IAC already to go. thats mounted in place of the STock TB but a little further back.Your imputs for your ECM are: TPS(gm),IAC(gm),Engine speed (green wire on the Fuel Dizzy), Coolant Temp, Air temp sensors(gm), ect..... Anyway Look up bill shaw's website "749 ecu 928" he can guide you i may have miss some things but thats the general route. it can be done for 600 bucks if you shop around and you have full tuning

michaelathome

The early callaway 944 set-ups ran a stand alone and used an extra injector on the fuel rail to accomplish the extra fuel delivery. Sloppy by todays standards but it worked for them. For more reading on the 944's see this link. On an early I can't see why you couldn't just double the set-up.

https://rennlist.com/forums/showthre...light=callaway

There are a few turbo 928 owners on the board that may also help you with the set-up.

<Turbo Flame Suit On!>

Michael

SMTCapeCod

I thought they were a couple months away from production on the WUR? I'm waiting to learn more about the design and its capabilities...and fearing its price tag...$625 isn't bad though.

Widebands are great for monitoring and for driving engine management systems, but often don't fair too well when in storage or going through periods of dis-use...which seems likely given the intent of the design here...