Aren't there several people running this configuration w/o drivability issues? [Maybe true, but not with pre-S4?] Has enough attention been given to get it running better with this setup that Ed and now you gave up?

 

I just got of the phone with Vems. I pulled the plug on a EFI system, no distributors and going with the 8 coil pack and a water/meth system with controler. I got everything I need I believe.

When I receive the product and start the install I will start a thread with some pics and results. They better be good or I will shot myself!

Thanks for all of your help!

Here we go!

 

You are a braver man than I am , good luck with it.

 

Thanks greg. Time will tell!

 

Is the VEMS compatable with the factory timing ring on the car?

BTW, you mentioned earlier in this thread that we are doing a MS conversion here in FL. Yes, thats true. The reason for this is because the two cars getting the MS are 16V cars that came stock with L-Jet engine management. If I had an LH car I wouldn't be doing the conversion. Good luck with your conversion.

 

Thanks Fabio. Yes they said it would work with the factory setup. Thanks for your help and input.

Kinda nervous, just going by my gut which can be dangerous!

 

Stephen,

FYI, all that car needs is a proper SharkTuning in the lower RPM ranges.

It would also be helpful to replace the Adjustable Fuel Pressure Regulator with a Stock S4 FPR to eliminate the possibility of user adjusting of the FP which is part of what is currently causing the lower RPM issues.

BUT, the main reason is that it has NOT been tuned below 4K rpms in it's curent configuration. Each time Ed upped the boost on the setup he would temporarily readjust the fuel pressure to compensate for safer fueling on the top end until I could come down and retune it for him with the SharkTuner, but we only tuned the upper RPMs and WOT per his request.

This was done on 2 occasions as boost was increased from approx 6 to 9 psi or so. On both of those occasions Ed wanted me to tune for 4k and above ONLY as that was all he cared about for the way he drove and used the car.

It was funny, I asked multiple times during multi-hour long on road tuning sessions if he wanted to tune below 4K and and that I could make it get better fuel mileage, drivability, etc, etc....he would just laugh and say he never drove it like that and wanted to concentrate on the upper powerband only for the upcoming race etc.

I would still have tuned in those area anyway, but sure as heck we would drive for an hour or more and he really never would be below 4K for me to even try to adjust those areas.

One thing I remember distinctively is that even after an hour plus of truly driving that beasty in "full anger" non stop continuously from 4k to redline over and over....the temp gauge never moved pass halfway on the gauge and the ST log files also confirmed how cool it ran...pretty amazing!

Nice ride you picked up...I would highly recommend getting together with someone with a SharkTuner 1 with the EZF option and do a complete tuning on it as it has never been done in it's current configuration. If you do that you will forget about messing with any other Engine Management system..AND you can continue to enjoy the car as it was intended, ie. driving it.

I fear if you start down the road of putting on an aftermarket system, my crystal ball tells me you are gonna have much less seat time in a fanatastic 928 for quite a while as you try to get it all sorted out.

Best of luck and let me know if I can help you with anything you need on it.

Dave

 

DR Thanks so much for your post. Since reading it I cancelled the Vems system but I still bought the Water Meth system. Then I will figure out how to get it tuned properly and go from there!

So who can tune this bad boy?

 

Dude!! Stay away from the meth.

 

I think not trying to reinvent the wheel is a good idea here.

 

You are welcome. Wise decision.

Anyone that has access to a SharkTuner 1 (preferably one with the EZF option for Igintion tuning) AND that knows how to use it and tune an engine. No different from tuning any other 928 with a SharkTuner.

I no longer have an ST1, but if you can't find someone with one near you I can arrange to get a loaner. There are a bunch of guys near you who have a lot of SharkTuner experience that could tune for you (but, I think they all have ST2s??), if not, I am sure we can work out some arrangement to get it all dialed in for you.

Cheers,

Dave

 

John Kuhn can do it. He flew down and tuned Abby's 86 turbo.

Tim Murphy can do it. I'm sure Z would like to visit the southern climes during winter.

See if you can't find someone closer first.

 

The LH-EZK system with sharktuning is VERY GOOD......when you add in the new MAP vs MAF airflow it is on par with the best aftermarket systems out there....

Mark Anderson and Joe Fan run a single MAF with dual throttle bodies on the carbon fiber intakes.....just put the MAF upstream of the dual TB's....on their cars its pretty simple.....filter-maf-TB-engine

However with a 79 things get HARD fast....since you will have to dump all of the CIS (I don't like it) and go stand alone.....it might be easier to go megasquirt vs LH....

 

To correctly tune you should modify the EZ-F and fit a 2 Bar MAP sensor in place of the stock 1 bar unit.

With the addition of a Knocklite or similar (as per Porken), connect the knock output to the available Aux input of the ST1, you can properly tune under boost. John Kuhn can do the MAP conversion, it was done on a couple of cars, including Abby's.
http://www.kuhnperformance.com/contact.php

 

Unreal what that one modification did for the entire set-up!