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Kennedy
10-04-2011, 06:26
Rendezvous 2002 in BC Canada. How many remember this one?

I was just reflecting on a comment that I made there at the DAS facility after doing what at the time was a very impressive burnout with my 2002. I remember saying I'd like to hit 400HP and that would be good for me. At the time I had rolled 376 I believe. Well 400HP was eclipsed and I ran for a long time at 450-470. This wasn't enough so I started stacking mods again. With nitrous I ran 739 RWHP at Weekend on the Edge 2005. This blew people away. It wasn't the highest HP of the time, but very close and those who ran higher mostly blew up. This setup ran for a couple years untile EFI Live came out giving me the opportunity to do my own tuning. My fuel only HP went to 500. Nitrous HP remained pretty consistent as I knew I was well past the limits of the stock components. In 2009 this engine finally gave up (autopsy still pending) with a pop but miraculously everything remained inside the block.

In 2010 it was reborn with compound turbos and a larger single CP3. It ran in the 840's, but we had problems with the head castings being porous so it had to come back apart. For 2011 it received the fueling that it needed so badly in the form of a second CP3 and an install kit from MPI. It now runs at 1000+ and has room to grow to probably 1200. A mere 3x what I had considered my objective just 9 years ago...


The reason this all came to mind was a trip to the track this past weekend. I got a rude awakening to the fact that my shift related tables were NOT going to cut it any more and I need to spend some serious time working this out. What I did find though is that at a weight in excess of 7700# I can run teh 1/4 mile in 11.7 seconds at 124 mph. The ET is actually poor considering the MPH acheived, but that's on me and my shift tuning. I had my 60' time at 1.9 which I can live with for now. I still need to redo the front brakes for some better holding power t the launch and focus will be on shifting for the time being. I can always revisit my launch technique later.


My point: The duramax is very tough in stock form and way tougher with the proper aftermarket parts installed...

Mark Rinker
10-05-2011, 14:38
Impressive. Thanks for the post! Wish I had a truck to 'play' with, that didn't need to haul the freight everyday...

SoTxPollock
10-06-2011, 10:05
Ditto on how tough a Duramax is. Tell me how long do you have to cool it after a 11.7 second run before you shut it off. My last 11.7 second car weighted in at 3047 pounds your truck weights more that twice that much. Incredible 60 foot time for that much weight.

DieselDavy
10-06-2011, 10:44
Congrats John!
Those are impressive numbers! (all of them, even those back in the days)
We're lucky to have you here for your advice and as a supplier.

Kennedy
10-07-2011, 12:24
Ditto on how tough a Duramax is. Tell me how long do you have to cool it after a 11.7 second run before you shut it off. My last 11.7 second car weighted in at 3047 pounds your truck weights more that twice that much. Incredible 60 foot time for that much weight.

It actually manages temp quite well. I have the idle speed programmed to ramp up if ECT crosses 200°f. After a truck pull it will often run fast idle, but at the track there is plenty of air flow. Oil temp on the day never topped about 198°f as I recall.

Not sure when I'll get back to the track, but I'm quite certain it has high 10's within range. My 60's will come down a tenth or two also once I get some practice.

JohnC
10-07-2011, 16:29
What I did find though is that at a weight in excess of 7700# I can run teh 1/4 mile in 11.7 seconds at 124 mph.
When I was [a lot] younger, I could turn in similar times with a Corvette...

Kennedy
10-10-2011, 07:45
We were going over the logged data Friday and it became apparent that the TCC was not applying hence the RPM's running wild until about the 1/8 mile. Once it locked up the motivation commenced.

So it looks like I'll be adding a lockup controller to get the lockup issue cured. I expect much improved ET's once lockup happens and I get the shift flaring handled.

Mark Rinker
10-10-2011, 11:15
Hmmm...anyone else predict some serious (additional) wheelspin? :D