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Discussion Starter #1
Well, I went to the track yesterday afternoon and flogged the 1/8th mile for a while. It's a brand new engine so I took it kinda easy, I still need more carb (another reason I didn't crank it too hard...didn't want to lean it out), and I ran most of my runs in "drive". Still need a manual valvebody, the first one I bought was defective so I'm still running my transgo shift kit VB. Made a soft pass to get everything up to temp and feel the car out, ET was a wash. 2nd pass dropped the ET streets to 14 psi, did a good burnout, staged and came off the line just off idle in drive. Mashed the gas & spun the tires a couple of feet. Pulled a 1.63 60ft, 7.49 ET @ 92mph. Only time the shift light (5800) came on was just before the traps. 3rd pass dropped psi to 12, same scenario as 2nd pass. Pulled a 1.61 60ft, 7.52 @91.....feathered the gas about 2/3 track because I got the sidewall wiggle. Made a couple more passes @ 7.51/ 91mph. Checked the plugs a couple diff times to make sure I wasn't leaning it out. Decided to make one more pass and pick it up a little bit. I bumped the timing up a couple degrees, Set the shift light at 5900, and put it through the gears manually. Made the best pass of the evening. Pulled a 1.59 60ft...still spinning slightly, and ran a 7.40 @ 93mph. I didn't set the world on fire, but I think it has quite a bit more in it once I get a bigger carb and am able to spin it up to a 6200-6400 shift point. I also want to take some gear out of the car, to utilize the motors torque a little more. Although I wanted it to be quicker out of the box, I still had a blast. I was used to my old motor nosing over at 5400, this new one pulls like crazy without a hint of flattening out. Can't wait to go again, with everything ready to go "balls to wall".
 

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Sounds like you had a decent first outing. What gears and size carb. are you running? Do you have slicks you can try?
 

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Discussion Starter #3
Currently a 650dp, gonna try an 850 next time. 4.56 gears for this trip, slipping in some 3.73's for next time. Running a 9", so gear swaps are pretty quick. no slicks, may be able to borrow a set. I don't think tires were the problem, track prep was pretty crappy/nonexistent. Plus it was 96 degrees and 52% humidity.
 

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Currently a 650dp, gonna try an 850 next time. 4.56 gears for this trip, slipping in some 3.73's for next time. Running a 9", so gear swaps are pretty quick. no slicks, may be able to borrow a set. I don't think tires were the problem, track prep was pretty crappy/nonexistent. Plus it was 96 degrees and 52% humidity.
The carb swap will give you a good gain I think. Also, if you are planning to shift about 6400 the 3.73 to 4.10 ratio is better for sure at the finish line. With the mentioned gear depending on the converter slip you should be crossing about 6400-6800.
 

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Carb swap will help, but don't worry about "leaning it out" with the 650. Leaning out a motor means you are getting more air than fuel. If the carb is too small and you put a little bigger jet in it, you are not going to lean it out, because its not flowing enough air into the engine in the first place.
 

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Matt:

You and I have similar combinations... Well 408w, Jay Allen cam, and automatics... I am running EFI... I have put down a 1.49/11.09/120.91 pass as a best... I believe I can get it into the 10's by manually shifting... My 1-2 shift happens at 5800, but my 2-3 happens at 5500... The car falls on it's nose after 6,000 which is a little disappointing... Jay indicated it should pull all the way to 7,000...

Wish you well...
 

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Discussion Starter #8
N2OJnky, I'm hoping I can get down to the 10's and keep it NA, if not nitrous will get it there. What was your 1/8th mile time/mph? What gear you running and what does your car weigh? What tire do you run? PM your cam specs, I'd like to see how they compare to mine if you don't care. Mine is a hyd roller w/crane linkbars. Did you call Jay and talk to him about your cam and what the problem could be?
 

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Matt:

I don't have my timeslip in front of me, but I know that I have run 7.0somethings in the 1/8th... Can't remember the speed... I am running 4.10's in the rear end, which will need to be changed out to 3.73's or 3.55's because I am trapping at 6,300 RPM with 6% slippage. My car weights 3320 when sitting at the line... I am running 275/60/15 MT DR's with Eibach springs and a ARB... I am also running a hyd roller cam with cran linkbars... I will PM you the specs... I have not called Jay because it has been 4 years since I got the cam from him and just finally finished the car...
 

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Discussion Starter #10
I think Jay would still be open to helping you diagnose the problem, he has been very helpful whenever I've talked to him. He is direct and to the point, and doesn't "sugar coat", some people don't like that, I prefer it.

You have good 60 ft times, especially for the car weight and the tires your running. Do you use a t-brake? How do you launch?
 

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Matt:

I am sure that Jay would assist... I'm not too excited about pulling the engine and doing much right now that I got everything together and running... I'm going to put on a mild 50 shot to take it into the 10's... Anything more, and I will need to re-gear the rear end... I do not use a t-brake. The car has always launched very good... I am running Eibach springs in the rear, 4 cylinder up front. 70/30 struts, ARB, and have the battery moved to the rear of the hatch... I stage the car, footbrake to 1500 or so, and put it to the floor on the third yellow... It is very consistent with 1.50 times...
 
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