9.19 @ 145.5 For The Alky Car

Don,

Congrats! I was there and saw the new best, that car hauls!

Very impressive.. I looked it over at least 20-30 times this past weekend!

Thx!

Makes me happy to know people enjoyed it. Thanks for the comments.

Wasn't exactly a .3 but it was was definitely much quicker than normal. Still reviewing the datalog and trying to figure out exactly what happened. If there is any way I could get that raw footage from you it would help out a bunch! I'd compensate you for it if need be. See you at Barona in a few months!

Scott Wile

I'll post it for you in the video section. May be a few days. Remind me if I seem to have forgotten.

Good Job! I always though your car was really neat. It is nice to see something different that works real good.

As soon as I can get this software to work right, I'll post some vids. It's amazing how it just sits there quietly, waiting for the tree and then, WHAM! Someone described it perfectly. It's just like a N/A car. Just imagine if I were to go WOT on the first amber, rather than waiting for after the second amber. Oh yes! Fear not. Those tests will come. :tongue:

Don-
I one of your 9.2* runs last weekend. I was impressed with how you just stayed at idle until the 2nd amber, then spooled and launched in a heartbeat!
How high do you rev? It sounded like ~8-9k rpm from the stands?
Congrats on the new best!

No, they are sitting around 5k now I believ. But we blew my last Art car converter up 2 weeks ago. Its a bitch trying to get the 91.5 turbo tuned just right, but we are getting there. Its simply not effiecient, until 24-25#'s, then its a beast!

Don, what block are you running?

Thanks Dan. And congrats on the bracket winS.
I was trying different shift points on the last three runs. On one of the three I hit the rev limiter in first. The limiter is set at 7800 rpm. The shift points for the 9.19 run were both about 7400 rpm. The other runs were closer to 7800, which might have something to do with the slower times for those runs. I typically shift it at 7400, but wanted to try the higher shift points to see if there was anything there. There isn't.

What size shot are you using? You may just need a larger shot. If you're not port injecting the stuff though, I'd be careful.

Thanks Chris. Your project looks to be going nicely also.

TA's block.

I've posted a compilation of all my runs made on Sunday on You Tube. DRW at WCN.

You were right on with your assesment. After studying the datalogs, I found that the boost was declining with engine rpm. It would peak to 29-30 psi by around 5600 rpm and ramp down to 25-26 psi by shift point (7400). After the shift, boost would be back up and then trail off again to 25-26 psi at the upper end, crossing the finish line at 25-26 psi. That would explain the low mph. I think the pure T76 is just at its limit, running out of breath. Otto, why did you get rid of the 4580 so fast?

I sold it cause i sold the whole car and motor.

I wasnt completly impressed with it.
But maybe i was doing something wrong.
Precision had a 4508 that was a great peice(81.5mm)
At your stage I would order one of the 47-88s in the small T4 housing.
I think its the best thing out there for Stage 1 style heads.

I just checked out the compressor map on the 4718 (88mm). That compressor would be very efficient with my setup if I could get it to spool. I figure the HP ceiling for my setup is going to be around 1200 @ 40 psi, if I ever chose to push it that far, making the 4718 perfect.

The nitrous system I'm using has a natural soft hit character or progressive rate feature to it. I figure that the engine is only seeing about 70 hp from the system before its turned off at 18 psi. The longer the system stays on, the higher the HP level at the time of turn off. I figure that a larger turbo is going to be harder to spool which means the nitrous system will be on longer to reach its 18 psi turn off level, which means a higher hp level will be obtained for a longer period of time to help spool the larger turbo. It could work well without much of a change to anything else except a switch to larger fuel nozzles.

I think you may be right on with that prediction. I figured if I could maintain 30 psi through the whole run, I'd be approaching mid 8s in the mid 150s if I wanted to push the rpm that high.