Fastest928

The MS is simple and works really well!

Anyone who can successfully program an engine mgmt system for all around use, similar to the factory programming, in 100 hours....is fooling themselves. You are off by 2 digits!

We have achieved over 550 rwhp wtih the stock setup and custom intake, but drivability is still not a no brainer...still take many hours of dyno work.

Any engine with HP peak in the 6500rpm range cannot be successfully tuned with the ST and stock electronics.

marc
survivor of tuning 928 with DTA, MOTEC, FAST, MS and others

mj1pate

Hello Marc....

Not having tried any of this (and reading between the lines), it looks like you're suggesting that extracting extraordinary HP from near stock engine essentially makes the car a track car, maybe needing a trailer to transport it way from the track(?)

Have you had a project focusing on tuning a stock engine for near stock performance with MS? How did this turn out? Did you have drivability issues in this situation?

Thanks

Mike

BC

Mike, maybe your question would be best asked here: www.msefi.com A Car is a car, even if we are aficionados of one or another. Alot of MS specific info there.

Lizard928

mj1 pate, getting the basic AFR dialed in across the rpm band really isnt that hard to do, it is getting the accell enrichment, cold start, hot start etc which can be fun trying to setup.

John Speake

Hello Marc
Can you explain what you found ?

Vilhuer

When Louis made decision to use what he uses was ST available as viable option? Would he make same decision now?

John Veninger

Maybe should have stated 100's, but 10,000??

John Speake

I hope Louie will join this thread, but the SharkTuner was not available when he made his ECU choice.

He told me he would have used the ST, and I know he has spent many, many hours tuning his 928 from scratch - and he has his own dyno !

For his type of setup we could probably have allowed for a MAP sensor for airflow, or even the type of throttle switch with a variable resitance vs throttle angle.

We have always said that we will adapt the ST to customer reuqirements.

SwayBar

Unless you're totally into this type of thing and truly find it fun and rewarding, it is simply not worth the time with a low-horsepower car as it will take 100's+ of hours just to come close to the all-around driveability of the stock system. If the car were pure-track, then this would not be an issue.

As for high-horsepower 928's, the threshold for the stock system with the SharkTuner appears to be 700 crank horsepower as the SharkTuner 'only' supports a max-size of 42 lb injectors.

With that said, just how many 700 crank horsepower 928's are out there? And of those few, how many of those will go for more? Not an appreciable amount in either case.

Vilhuer

This is not a problem at all based on what I have seen Niklas do.

SwayBar

Are you implying that the SharkTuner can support injectors greater than 42 lbs with some software tweaks?

If that's true, then I think there is an issue where 42 lb injectors are the largest available with a 16 ohm resistance, or something like that...

Vilhuer

What injectors 951 people use? 56 or something like that. I can't remember what Niklas has said about larger than 42 but I'm sure its doable fairly easily. John should know I'm sure.

Besides, there is always option of raising fuel pressure. Fow limit of Super MAF is other limitation which can be worked around if need comes.

NickT

a question of ignorance... Whats the difference between the regular MAF and the Super MAF?

Vilhuer

Its true that 42 seem to be largest possible injector which works in 928 directly. But there are several workarounds for this. Easiest is to raise fuel pressure. If 42 is good for 700 hp in standard S4 pressure I think close to 1000 hp should be possible with RRFPR. Still not enough? Use larger injectors (need different driver, most likely doable but idle will start to suffer as injection time gets too small in low rpms) or add other set of injectors side by side (need some system to trigger them, most likely doable without too much difficulty).

Super MAF is not limiting factor either. There are several workarounds for this too if really needed. Nick, check John's previous messages on what Super MAF does.

If fuel map rpm range spacing is problem in SharkTuner and there are not enough cells up high in range its possible to move them from lower down to allow more precise adjustment in high rpms. Obvious drawback is little worsening drivability in low rpm range. I think there is same problem in all systems which use 16x16 map. Rpm range can only be spit into 16 parts. In 928 stock system what SharkTuner supports most cells are used in low rpm to make normal driving easier.

I think there are several more pressing problems than LH and EZK tuning when building 700+ engines for 928.

John Speake

The SharkTuner is able to support injectors up to about 66# without idle being adversly affected.

Just select "custom" in the injector size in the "Parameters" screen.