Ispeed

Yes, but E60 M5's are a dime a dozen, and will be pretty expensive to service/own and the prices will keep going down. A 928 will always be a special car.

killav

I can vouch for that. John's (Soontobered) cousin owned a 2002ish M5 with the V-8 and manual trans. He let me drive it from his place to mine a couple of years ago-about a 10 mile drive. He really let me wring the thing out.....that car was quick, the transmission was like butta, handling and ride were superb. Couldn't image what the V-10 pulls like.....and Andy's GTS is even above that.....

hacker-pschorr

What's your point? There are a lot of cars far more expensive than either of these that are slower than a stock Corvette.

What's with all the kill-joy's around here lately?

GregBBRD

Last time I talked to Andy, he hadn't had the engine much past 5,000 rpms, which I can fully understand....there's a "learning" curve with this vehicle.

The times that I stood on it, while tuning, really got my attention. Between 5,000 and 7,000, things happen really quickly. The tach is literally a blur, in second gear. Third gear gives you more of a chance to see the tach, but by that time, things are moving past the windows fairly quickly....and I needed to watch the road.

It's pretty easy to "bounce" it off the rev limiter, if you aren't paying attention.

FredR

Andy,

Impressive numbers on the dyno- with torque peaking at/around 6k must make that motor beg to be thrashed. Enjoy!

Regards

Fred

Jon B.

Because...

You people don't read anymore? We aren't allowed to answer questions?

I'm all for the 928. I do DD one after all. I sold my Corvette for my car and I don't regret it one bit. I wish I could afford what Andy has into his GTS, and I would MUCH rather have it than any M5.

dprantl

As I saw a grey S2000 this morning on the way to work, I don't know why but I got this post on my mind. Too bad for him, he tried his best. On a highway on-ramp where two lanes merge to one just as there is a moderately sharp right turn, then the merge lane continues on the highway for almost 1 mile before turning into the next exit. I let him get in front from the light, then at ~50mph I down-shifted to 3rd and pulled to the left lane. He was already pulling pretty hard, but I saw the black plume of smoke so I knew he went to WOT. After 2 seconds I was in front of him just as the turn began. Wow, the 928 handled the turn at WOT absolutely flawlessly. 6,800RPM and shift to 4th, on the highway now and hold it until ~6,200RPM in 4th, he was 7 - 8 car lengths behind now. I'm not boasting, just having fun

Of course, this all just happened only in my imagination.

Dan
'91 928GT S/C 475hp/460lb.ft

m42racer

Been away for sometime travelling. Just caught up with this thread and realised it was the same engine as in the previous thread. Man it sound awesome.

So the power is there, how is the throttle response? What are your impressions of the EFI system and how it works? How was the programming and its use? There are a ton of different systems out there, but not many used on 928's. You said you were going to make some changes, was it easy? If the power is there, something must be working well with that awesome engine.

GregBBRD

Might be best to get Andy's thoughts, also.

I think the car runs like a stock 928, when cruising around. I could never tell that there were ITB's on the engine...it's just like it had a single butterfly.

The Link system is really nice. Very straightforward and easy to figure out. The downside to it (and actually to any injection system that you start "fresh" with) is that there are a lot of different tables that need to be addressed and figured out, for the car to run smoothly and act like a "stock" vehicle.

We did full throttle fuel and timing, on the dyno....and that takes quite a bit of time to do properly. Neil is very careful about tuning and not killing the engine. Once the engine was in the car, then I did the remaining tuning...with a few phone calls to Neil.

The most important thing that I learned is that tuning takes serious time.

Charley B

Always the master of the understatement.

(sorry for the slight editing)

m42racer

Its good to hear other opinions on these aftermarket systems. I suppose reading what you said, it does come down to the people involved in the tuning and the systems are only as good as thise using them.

andy-gts

No problems at all with the tuning done by greg....the big cams with the auto idles nice and throttle response is very crisp from 1 to 2 k then immediate there on up! Idles at 1000 rpms in park and in d,3,2, down around 675.....very nice.!
I really havent hooked up my computer with the link g4 extreme brain yet but will soon . I need to get a reliable battery for my laptop first , finish some carpentry for my daughter etc....

m42racer

Greg,
I'm interested in hearing your thoughts on the EFI system and the tuning. I have 2 of these systems on two engines at the present. I was never around during the tuning, but have had changes made since and each time the system worked perfectly. So I'm kind of biased on the Link as could be expected. But its always good to get a clean opinion by someone who has also used it. There are so many EFI systems to choose from out there, some really good and some just OK.

The question would be, would you do it again, would you use it again and is it a good choice for these engines?

GregBBRD

The hard part of any engine development is....the development.

I needed to do some serious engineering, for this project to come to fruition. Initially, we were faced with a lack of camshafts that were appropriate and had to solve that problem. We then had some "cylinder head flow" development work to get through, when using ITBs. Next came the oiling problem that we found on the dyno, at high rpms. Tuning, although requiring significant time, was relatively easy to figure out. Hooking this engine up to the automatic transmission and making the engine idle correctly with the automatic transmission and making the transmission shift correctly was very difficult and very time consuming. (One example of this: Porsche "reduces" the igniton timing when these engines shift (to reduce torque) in the stock application. I realized that with the increased torque, this would be a necessary thing to retain, with this engine. Making that happen took serious engineering.)

When all said and done, this was a pretty difficult project and it "sucked" up a lot of developmental hours.

However, now that it is done and all of those items are figured out, the next one will be much easier. I have a "base line" Link program, now. Although it is for an automatic, it will be close to correct for other high output applications, with minor "tweaking".

Do it again?
Certainly.

Use the "Link System"?
Absolutely.

Appropriate for these engines?
Easy to understand. Easy to make changes. Easy to accomplish what you are attempting to change. Yes, it is a good fit, with these engines.

cobalt

Do you know what mode the M5 was in and did you have more than one run with it?

I played with an M5 with my turbo and the first two times I pulled like there was no tomorrow the last run he gave me more run than I imagined in return.

The M5 has 2 power modes and if you are not in the power mode you have around 350bhp available. Huge difference when in power mode and not something you can switch on the fly.

Not saying you aren't fast but if you caught him off guard you might have felt as though you had more on him than you did. I am sure he figured he didn't need to power up for an older 928 but I could be wrong.