Camaro XV

[LS7 Z/28]

Originally Posted by mikels

Mark and I were talking that we've reached point where more power is not likely to result in much improvement of lap times (never thought I'd say that.....

Mark Donohue would be proud!

[PTAddict]

Originally Posted by mikels

Controller is GM E67 and is using MAF primary control with parallel speed-density control. So I have seen what you are speaking of, but this is slightly different.

Flames are result of how quickly ramp out of PE (power enrichment) combined with spark control when transitioning from on throttle to off throttle to DFCO (de-acceleration fuel cut-off).

Non-issue from an engine standpoint - from a visual, well, it barks flames on lift-throttle transitions from high airflow.

While there are many changes I can make that could reduce this effect, we haven't had time to revisit cal since last development trips to Gingerman and now OUSCI. That and some of those potential changes would be undesirable such as how quickly power drops when reducing accelerator pedal (@ 950hp, when you lift, you likely really want to reduce power.....)

Mark and I were talking that we've reached point where more power is not likely to result in much improvement of lap times (never thought I'd say that.....). Ability to maintain fluid temps at this power level has been a challenge as well - but Mark is now able to run 20 minute sessions in any ambient with controlled temps and no drop in delivered power.

First 7.0L supercharged engine (for road racing) we did at Thomson's in 2009 made 780hp/830tq. We are now at 950hp/970tq (1010hp/1020tq on E85). Amazing what refinements can bring paying attention to the details.

Dave

It really is an amazing accomplishment making this kind of HP, pump gas, thermal management, and totally drivable. Crazy good. All on a production block and oiling system, as well.

Does the E67 ECU have any advantages over the E38 for this kind of application? Also interesting to note that you're running hybrid MAF/Speed Density - SD tuning on those ECUs is a PITA, at least with HP tuners, and I've found no discernable advantage in normally aspirated performance applications (the GM crate motor ECUs all run MAF-only as well). But it may well be that, at this HP level, that extra bit of fine transient control is important?

[PTAddict]

Originally Posted by formula88

Here's a video from the final road course session (about 1/3 into it).

It gets really wild about two minutes in .

Some really sweet driving by all and a great perspective on how hard these guys track their cars.

Very cool video. Thanks for posting.

The track looks tighter than I expected when I think of LVMS. Seems like it might be less of a "horsepower track" than Spring Mountain?

Interesting to hear how much those Rival street tires squeal under braking and through the turns. Hoosiers don't make that kind of noise unless you're spinning out. Not that I would know

What motor does Maier have in that Mustang of his to be able to almost keep up with you on the straightaways? Seems like a bit more than a 289 with a tune up

[glassman]

Originally Posted by PTAddict

Very cool video. Thanks for posting.

The track looks tighter than I expected when I think of LVMS. Seems like it might be less of a "horsepower track" than Spring Mountain?

Interesting to hear how much those Rival street tires squeal under braking and through the turns. Hoosiers don't make that kind of noise unless you're spinning out. Not that I would know

What motor does Maier have in that Mustang of his to be able to almost keep up with you on the straightaways? Seems like a bit more than a 289 with a tune up

SB2 cup car from what i heard. Great battle.

[GregWeld]

Originally Posted by PTAddict

It really is an amazing accomplishment making this kind of HP, pump gas, thermal management, and totally drivable. Crazy good. All on a production block and oiling system, as well.

Does the E67 ECU have any advantages over the E38 for this kind of application? Also interesting to note that you're running hybrid MAF/Speed Density - SD tuning on those ECUs is a PITA, at least with HP tuners, and I've found no discernable advantage in normally aspirated performance applications (the GM crate motor ECUs all run MAF-only as well). But it may well be that, at this HP level, that extra bit of fine transient control is important?

If you got to drive the car on the street.... you'd sell your house and buy a sleeping bag and move into the car if that's what it took to own it or one like it. LOL

Your Grandmother could drive this car home (to Pasadena) and be happy!

[66tintop]

Originally Posted by GregWeld

If you got to drive the car on the street.... you'd sell your house and buy a sleeping bag and move into the car if that's what it took to own it or one like it. LOL

Your Grandmother could drive this car home (to Pasadena) and be happy!

I have read that everyone says u suck ! But , I'm going to say , your one lucky bastard ! I'm sure all the rest of those other guys are drooling and tripping on their lower lip ! Me included !

[PTAddict]

Originally Posted by glassman

SB2 cup car from what i heard. Great battle.

Oof, that explains it. Not exactly an ideal cross country cruiser then. But I'll bet it's a ton of fun on the track.

[PTAddict]

Originally Posted by GregWeld

If you got to drive the car on the street.... you'd sell your house and buy a sleeping bag and move into the car if that's what it took to own it or one like it. LOL

Your Grandmother could drive this car home (to Pasadena) and be happy!

Well, I've been trying for a long time now to own one "like it". Problem is, Stielow keeps raising the damn bar But I'm having a ton of fun chasing that dream anyway.

[Flash68]

Originally Posted by glassman

SB2 cup car from what i heard. Great battle.

Come on Mike, really?

SB2/SB2.2 = Chivy

And that ain't no Chivy.

it's a Roush Yates 358... at least it was before the rebuild. Not sure if Mike modified it/stroked it or whatever for the current iteration.

She's a beaut though

[PTAddict]

Originally Posted by Flash68

Come on Mike, really?

SB2/SB2.2 = Chivy

And that ain't no Chivy.

it's a Roush Yates 358... at least it was before the rebuild. Not sure if Mike modified it/stroked it or whatever for the current iteration.

She's a beaut though

LOL. Truth is, though, with NASCAR rules the way they are Ford/Chevy/Toyota cup motors are much more alike than not, and all quite different now from production Ford/Chevy/Mopar small blocks. I'm quite sure I couldn't tell them apart by sight.

Would love to hear some video/sound clips of the Maier car too.