Lizard928

probably not that many,

but you also have to take into account that the factory tuning isnt near the limit at all, with alot more ign advance (may require higher oct fuel) and a better fuel map you could see substantial gains through tuning, and more efficent when cruising on the freeway

kjurkic

HMMM My last reply didn't get posted...lost in space somewhere

To clarify my goals:

Modern EFI system so that I can optimize the fuel delivery, and because I don't mind tinkering. I can also move to newer, better, *less expensive* injectors; I don't know if L-jet supports this.

I have plans to add some form of boost a year or 2 from now, so having the MS in place, and already having practiced with it, one less "X" factor to deal with.

21st Century V8's are getting 30+MPG while still cranking out 300HP (friend has new Mustang GT that accomplishes this). I didn't buy the 928 for fuel economy obviously, but I see no reason I shouldn't be able to come close to this with modern controls.

There will always be debate about OES components vs aftermarket, and there is always the "if it ain't broke, don't fix it" truism.

I don't want to get into a project that will leave the car stranded for weeks or months, but I also would like to get the most efficiency I can out of the system.

I don't plan to cut any existing wires, and will run a complete parallel harness if necessary, and keep all the original pieces for a roll-back option.

I want to thank all of you that have replied so far. The more that I can absorb before diving in, the less likelihood I will have to repair a major screw-up (such as a blown engine from too lean a mixture)

Regards
Ken

BC

And its fun.

plastex

I am going to go with the Megasquirt in my 83' 928 that is going to be supercharged as well. I did the CIS conversion on my 76'911 (Turbocharged). With the MSI you don't need any crank trigger. On my 76 I ended up using the MSD Timing computer to control spark and the MSI for the fuel. It was real easy. You will definately need the Wideband O2 sensor, specially if you SC the car. Even if you don't SC the car the Wideband sensor is nice because you can fine tune the car.

My only question is whether I will be able to use the Injectors and plumbing for them?, on my 76' I had to make Fuel rails since the CIS injectors are different.

There are a few of un on Pelicanparts that have done the conversion on the 911's if you have any questions as well.

Oscar,
Akron, Ohio

BC

I like the idea of new fuel rails because they are shiney and big.

Peter F

I know of at least two cars converted here in Sweden, one was equipped with a complete after market system for both ignition and injection and was super charged.(there is a thread on Rennlist with some pictures)
Here is a link to the other which only had the injection system changed.
There is a couple of pics (unfortunately for most of you the text is in Swedish ).
928 CIS to LH conversion

/Peter

Jim bailey - 928 International

Perhaps the 300 hp of the mustang has something to do with three valve heads,variable cam timing, and variable flaps in the intake as well as a zillion hours on the dyno ! The list of things to consider BEFORE changing the injection is typically a rather long one. Like compression , camtiming , ignition timing, wires plugs...then maybe all the rubber , hoses intake boots ,vacumn then put some miles on it to see how everything works ,what you actually have and THEN work on "upgrades".

kjurkic

*bling**bling* oooooooo shiney!

kjurkic

I didn't figure on getting as good numbers as the mustang; I know that there is whole lot more to it.

I have a laundry list of small jobs to do before the MS. I am just doing the homework, research, planning right now.

K

Jim bailey - 928 International

Enjoy the journey the 928 can be a wonderful hobby.

kjurkic

Thanks.

I already enjoy the expressions of jealous co-workers :->

Believe it or not, it was my wife who said "buy THAT one" from a picture she saw.

Regards,
Ken

Raceboy

I converted Euro 928S LH-JET to VEMS standalone with COP ignition and results are very nice. We smoked stock Euro S (both are autos) and I tuned the car to have really good economy: the best was 7,7-8 liters per 100km. That is NOT achieveble with LH-Jet.
I was more than happy to ditch those clumsy dual distributors and make a new harness to get some level of decency under the hood. Old, dirty, stiff and ugly wires are not exactly an eye-candy

Mike Simard

Raceboy, how's the VEMS to live with? Is it still a little buggy and being developed or would you let your grandmother drive a VEMS car cross country?
I'm thinking of using it, I've used megasquirt but feel that develpment has reached a crawl and VEMS sounds like it's well developed. Just to have COP ignition would be a dream, what COPs are you using?

Raceboy

I'm using VAG COPs and once installed, there's absolutely NO problems whatsoever. My friend who is not good in tuning drove the car almost all winter as a daily driver and we have here -30 degrees Celsius. Started everytime and worked ok.
Here's a thread about the VEMS install on 928: https://rennlist.com/forums/928-forum/296704-starting-stand-alone-install-on-86-4-7-a.html

sublimate

Doing fuel-only is pretty easy.
Here's a good page on doing ignition too:
http://www.diyautotune.com/tech_arti...on_control.htm