GregBBRD

I have almost zero confidence in any rear wheel dyno results. They can be affected by too many things. I use them only for direct comparisions, on the same day...or in the same week, at worse....and never try to compare results from car to car, much less dyno to dyno.

Heck, even here in Orange County, engine dyno results vary from DTS dyno to DTS dyno by 40 horsepower on a 350 horsepower small block.....what numbers do you want? Take it to a different dyno....you will get what you want to see.

The dyno we are using is absolutely the "tightest" dyno in the area. I like it to be conservative. It's way fun when someone with less power smokes someone with more horsepower.

I've watched too many 600 hp supercharged "rockets" get their door ***** sucked off by 400 horsepower naturally aspirated engines to even count them....and I love it.

Here's the reality: I know what I did to the heads. I know exactly how many CFMs each port will flow. I know exactly how many CFMs both Mark and Joseph's heads flow. It isn't too tough for me to calculate the potential differences/results. It's pretty much just a simple math problem, once you know that information. Running the engine on the dyno is more breaking it in, calibrating the fuel injection, and running experiments.

I was not unhappy with the power results. I was not thrilled with what I saw regarding some of the experiments we were running. I learned more, in that one dyno afternoon, about oiling issues with the 928 engine than I've learned in years....just when you think you know quite a bit and have it all figured out....you find out that you know absolutely nothing.

Enough said.

GregBBRD

Link. Great stuff, very reasonably priced, for what it does.

I like it so much that we will be making up looms for "turnkey" applications.

928mac

MMMMMMMMMMMMMMMMM SIMMMAAARRRDDDDD

btw gREG, . . . nICE CHEVY

GregBBRD

Turns out that the headers tuck "in" too much to clear the "post" on a DTS dyno. The spacers just allow the headers to clear. Yes, it will "skew" the power results...but only by a few horsepower.

As long as we have to use them, we are going to put in pyrometers for the next dyno test, in a couple of weeks....if we have time.

Right now, we are "applying" what we learned in our "experiments". After some changes, we will return to the dyno.

The engine did not get hurt...we were being very conservative with timing, as I mentioned...but we absolutely would not dare to go beyond 6,000 rpms...there is no doubt it would get "hurt".

LT Texan

Love the picture of the engine in the bed of the chevy truck! Must have turned a few heads!

TrackDays247.com

Lots of TME here.
Time
Money
Effort

BC

LINK G4 extreme? Great unit. Only think I think it lacks is a load based fuel trim - it has individual cylinder trims, but only global percentage changes, last time I checked.

Landseer

Now I understand better Andy's recent concern about flexplates .

IcemanG17

x1,000,000%

this is cubic $ territory.....the last thing you want is a custom built engine that grenades in 10 hours of less.....

Mongo

Ya that would not be a pleasant sight let alone sound..

Rob Edwards

I think the engine is about the last thing that Andy's going to have to worry about grenading....

andy-gts

Man that video is nice , thanks for doing that.

Greg actually stopped the dyno session before any tuning actually took place as he saw something he wanted to address.....but just seeing the process was way cool. I now see the advantages of the engine dyno., as there were no ignition maps or fuel maps for the new system. Greg had to start real conservative.
I wish I had a 5 speed as the cams he had made could have been wilder and still drivable but I am happy that the best will be under the hood.

Now I have to get with Tim Dey, the godfather of 928 ORRacing and start learning.......

andy

m42racer

Andy

Really nice. It must sound awesome in person.

Ah, Link G4 EFI. Good choice. I know this system as I have this on some of my engines. It's no wonder Greg is going to offer this for 928's.

So there's more in this engine to come if you never rev'ed to the limit and the timing was not mapped yet. Pump gas must make it fun. It's agood thing the Link EFI has kvnock control.

BC. Re check the software. In fact I think G4 from the very beginning has had individual Cyl trims with full 3D maps for each cyl. What do you mean by load based fuel trim?

Iwanna928

Andy You must be one happy boy! Awesome! I only wish. Goodluck learning how to drive that beast. Should be a BALL!

BC

Hey M.

When you have sequential fuel on the engine, each cylinder will get its own squirt - we know that. The reference that I made is that when each cylinder is in need of a slightly different fuel map, such as in a moderate length runner single-plenum individual runner application like this:

http://www.erik27.com/todd/turbo/index.htm

Some cylinders may need more fuel than others in certain loads and rpm ranges, and less in others.

As far as I know, there is a map for this cylinder trimming, but it is via a percentage change over the entire rev range, and not on a load/rpm form.

If you look in the software we can find this out. When my friend todd (who does the work in the pictures I posted) asked the VIPEC and LINK guys last year, that was the answer he got.