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Discussion Starter #1
Alright heres the scenario. The motor in my car is a stock bottom end, stock cam, unported E7s with GT40 valves and a valve job, 1.7 rockers, Cobra intake, 65mm TB, 75mm MAF, CAI, pulleys, Long tubes, x pipe, dumped spintechs, 3.73s, stock tranny, saleen springs on a stock suspension. Car dynoed a reasonable 258 rwhp 295 rwtq.

On 18" falken street radials its best was a 12.95 @ 106.0 mph. At the last race a few months ago the car was going low 13s but trapping 109 (best of 109.27). This past weekend I borrowed some Drag Radials to see what it would do.

First Pass: 18 psi, spun hard and in 2nd gear. 2.20 60' on the way to a 13.30 @ 107.4.

Second Pass: 18 psi, spun less but again in 2nd gear. 1.95 60' on the way to a 12.93 @ 107.6.

Last Pass: 16 psi, spun slightly less but again in 2nd gear. 1.93 60' on the way to a 12.87 @ 111.5.

Im wondering where that 111.5 came from. The car felt good, but nothing special in the SOTP department. It didnt feel stronger than my 109 mph passes, and even trapped a weaker 1/8th mph. I feel like this was just a fluke and the numbers all say it was. I hate knowing it was probably the timers at the track that messed up. The car weighed 3130 with me in it, no pass or back seat (sold them). 258 rwhp and 3130 do not come out to 111.5 mph any way you cut it. Even the 109 mph amazed me.

Any input, is the car a freak, or is the track in need of new timing equipment :D.
 

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you were spinning at 2nd or launching at 2nd?
 

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Discussion Starter #3
Spinning when I hit 2nd. I should have some video of the passes which I will post. I had that issue on the street tires, and hoped the DRs would solve it. Needless to say it was almost worse on the DRs. Im glad I have a 31 spline set up going in this winter. Then I can run my 17" ET Streets.
 

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I think it would be a timing fluke.

With even less tire psi, you should have trapped under the original times (all things consistent)
 

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Discussion Starter #6
Thats my guess, now what do I tell people... that was my best Drag Radial pass, so I have No other mph to work with for that particular run...

Oh well, one more race on ET Streets! :D
 

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I have heard of gusts of wind picking up on the tail section, pushing cars 3-5mph faster near the end of the 1320. Also, any chance motor could have went lean after the 660'???
 

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Discussion Starter #9
There could have been a wind thing, could have gone lean, could have been anything, I'm unsure. What gets me is the fact the car picked up 26 mph on the big end, where it normally gains 22-23. Now when we look at how much faster it went from the 1/8th to the 1/4 time wise vs mph wise it doesnt even out.

I'm chalking it up to a timing thing with the clocks, but what do I say about my best mph. Stick with 109.27 or tell people its been 111.52?

Either way the mph doesnt matter as much as the times!
 

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My bud runs 117mph through the 1320 consistant. The last past he made a few weeks ago, was a strange 122mph. This was right after two previous 117mph runs, no more than 40 minutes before. I say he went lean, but he says he's still happy with that trap speed. I say he should be careful next time he brings it to the track!
 

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The slip says 111.5 mph - 'nough said.

If it was unreasonable (think my 188 mph 1/8th trap speed in the '06), then you could call it a timing error. In this case, you only improved 2 mph. The air was better than last time, when you went 109 a few times. I had my best trap speed. Ken broke into the 11s for the first time.

Be happy - so long as a lean condition isn't hurting the motor.
 

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Discussion Starter #12
If it was the case of the lean condition, how do I get this to happen more often... :D

The slip does say it, and if anyone asks Ill explain them the situation. The 109 mph wasnt any fluke, so I guess I can use that.
 

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It could have been the way your car tripped the beams or a timing error. I doubt your car randomly went lean, you have a mass air right? If so it will correct it. I run on tracks all over the country and I'm within 1mph 99% of the time. Some tracks certain cars will trip the beams in a different lane. Kind of odd but it does happen. Run it again and see what she does. And I see some Enormus mph with E7's :)
 

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Discussion Starter #14
Yeah you guys do see big mph, but Im sure you have more money, effort and time into your heads than I do into my whole drivetrain :D.

The car last time out was going 108.9 - 109.2 and earlier in the same day as the 111 was going 107.3 - 107.4 ( I figure the 107 vs 109 is from the 18 psi in the DRs vs the 35 psi in the street tires).
 

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It could have been the way your car tripped the beams or a timing error. I doubt your car randomly went lean, you have a mass air right? If so it will correct it. I run on tracks all over the country and I'm within 1mph 99% of the time. Some tracks certain cars will trip the beams in a different lane. Kind of odd but it does happen. Run it again and see what she does. And I see some Enormus mph with E7's :)
Depends on the MAF. The tolerances are not that good.
 

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Discussion Starter #18
a quick look at your RPM when you crossed the line will tell the truth :)
I usually know around where the RPM is, and on this pass it was higher than the previous couple that day. Not sure compared with the 109 mph passes. I only have the stock Tach and its 1000 RPM off as seen on the dyno.

The 1/8 I dont have in front of me, but I think it was a mph difference between the 107 mph runs, which is another reason I think fluke. Huge tailwind might be true, but Im not sure.

Etown on some ET Streets will be the next race, so I will be praying for another 110-111 mph run :D.
 
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