Quest for 10's

Bill@HPTuners

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Plan to hit the track again soon? I'm local and would be happy to line up against you for a run or two :)

First time out with my procharger I was only able to get one run from a dig and ran 11.8@123 launching off idle so I definitely want another shot at running a better number :)
 

Five-o-Joe

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You were likely there without that missed shift; however, I agree with twin62cobra. Changing the gear ratio with either the gear or tire will make your car a consistent 10 sec car. The reason it is so "hard" right now is your peak number is there but your average power through the run is lower than it should be. That's why something "doesn't add up". So you don't lose the nice drivability of the 3.31 on the street, I would keep the 3.31s and switch to a true 26"x10" tire that will put you in your peak power range faster and keep it through your shifts. There's a lot of things that can be done to get into the 10s consistently but I think the tire change is the easiest and cheapest...
 

FL Skydiver

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You were likely there without that missed shift; however, I agree with twin62cobra. Changing the gear ratio with either the gear or tire will make your car a consistent 10 sec car. The reason it is so "hard" right now is your peak number is there but your average power through the run is lower than it should be. That's why something "doesn't add up". So you don't lose the nice drivability of the 3.31 on the street, I would keep the 3.31s and switch to a true 26"x10" tire that will put you in your peak power range faster and keep it through your shifts. There's a lot of things that can be done to get into the 10s consistently but I think the tire change is the easiest and cheapest...

I am beginning to wonder if the 3.31 gear might be holding me back. I still have the 3.73 gears in the garage and it would cost me nothing other than a crush sleeve a seal and some time to put them back in. If I knew for sure that I would run faster with the 3.73 gears I would put them back in since the car is not a daily driver. I think I would have to see if my tuner could safely raise my redline to 7500 RPMs though.

If I was to go with a 26" tall tire, I would need new rims since my race tires are mounted on 15x10" Race Stars. The 26" tall MT bias plys need a 7-9" rim.
 

twin62cobra

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You would not have to change your rims when switching to the 26x10 tires. I run a 10 inch rim with my 26x10 tires. If you run a 26x10 make sure you get the stiff sidewall tire, because of the weight of your car.
 
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Five-o-Joe

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Like twin62cobra said....your rims are fine with 26x10s. I too run 26x10 stiff walls on 10" rims.....works great. I prefer the stiff wall tires but of course, you can run whichever you like...
 

FL Skydiver

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Like twin62cobra said....your rims are fine with 26x10s. I too run 26x10 stiff walls on 10" rims.....works great. I prefer the stiff wall tires but of course, you can run whichever you like...

What kind of 60' foot time you running?
 

Five-o-Joe

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Not great......1.42 sixty foot.

I have a 3.55 rear gear and a T56 magnum with the 2.66 first gear. I would benefit from more gear myself due to my long first geared trans. If I had a 3.73 or 3.90 I would likely be in the mid to low 1.30 sixty foot times. Instead, I chose to keep the same rear gear and tire and add more power and torque. I'm now making 60 more rwhp and 70 more rwtq than previously. I'm looking forward to the track opening back up here....
 

gimmie11s

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Its a better idea to run a stiff sidewall drag slick on a 3700 lb car. This type of car is what they were designed for.

The 3.31 gears are not holding you back. You are going to need 128-130+ mph to crack a 10 and to get there in 4th gear, you must run the 3.31s.

A 3.73 with a 28" tire at 130 mph is 7700 rpm....

3.31 is a better choice and will be enough gear to get you to about 140 mph at 7300 rpm in 4th gear..... much safer.
 

Five-o-Joe

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Its a better idea to run a stiff sidewall drag slick on a 3700 lb car. This type of car is what they were designed for.

The 3.31 gears are not holding you back. You are going to need 128-130+ mph to crack a 10 and to get there in 4th gear, you must run the 3.31s.

A 3.73 with a 28" tire at 130 mph is 7700 rpm....

3.31 is a better choice and will be enough gear to get you to about 140 mph at 7300 rpm in 4th gear..... much safer.


The issue I see is that the car doesn't make the power currently to use the 140mph capability of the 3.31 with a 28" tire. The same 3.31 gear with a 26" tire though will run 130 at the same 7300 rpm and would likely be quicker. If the goal is 10s, I'd use the 26" tire and 3.31 gear. If you will be adding power soon, with the goal of running 9s, I'd keep the 28" tire...imho
 

DarkMach1

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Theres nothing wrong with your setup. its florida and this is why I went procharger, its a bit more consistent year around though it will no doubt love cool air. You need mods to keep that car cool, first thing I would do is purchase and install an ice tank and let it cool off between runs, dont let her get hot at staging lanes. You need to try to scope out the good weather days. I have a P1 making slightly less than 600, saleens in the back and 20" velgens up front, premium S550 auto and I went 10.8 at 128 with a 1.8 60ft at PBIR. Im getting 17x4.5 Forgerstar F14s and going back.
 

twin62cobra

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If you look at his video, he is only crossing the finish line around 6500 rpm. To get the max out of his car, he should cross the line around 7200 to 7500 rpm. Just imagine if your shift points should be 7500 rpm and you short shift every gear at 6500 rpm. You are leaving a ton of ET on the table. I do agree with running a 5 gallon or larger ice tank to lower IAT. Trust me run a shorter tire or change your gears and you will run 10.80 or better.
 

DarkMach1

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its a PD blower, it runs fine on a 3.31 gear. I've ran 305-40-18, 265-40-18 and now 285-40-18. Differences were minimal, but it felt a bit sluggish on the the launch on 305s, granted that was during the day at 85*, high humidity and stock stall, but times were slightly better. He needs to launch a little harder, keep the rpms up and rev a bit higher if you can afford it, car is still making power at 7000.

Are you using straight 93 with nothing in it? Are you looking at logs yourself? Hows the KR throughout the run? You might be able to upload it to datazap for all of us to check out, making an account there takes 2 minutes. Willing to bet car is pulling some up top.
 

twin62cobra

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With my SSO I shift around 8500 rpm and cross the finish line at 9000 rpm. In my 04 Cobra I shift around 6800 rpm and cross the finish line around 7200 rpm. My 04 Cobra runs 9.6 @ 146. The only thing I am saying is you want cross the finish line at the maximum rpm range no matter what horsepower level you're at.
 
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Five-o-Joe

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I agree. Id like to see a log before going in swapping parts.

Agreed....the car runs fine with the 3.31, but to run what it should run (better than fine) it could use some more effective gear. Regardless of the log, the car will put more average power to the ground in first and fourth with more effective gear (getting to peak power faster and staying in peak power longer).

Dark March, your car runs well.....is is manual or auto?
 

DarkMach1

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Agreed....the car runs fine with the 3.31, but to run what it should run (better than fine) it could use some more effective gear. Regardless of the log, the car will put more average power to the ground in first and fourth with more effective gear (getting to peak power faster and staying in peak power longer).

Dark March, your car runs well.....is is manual or auto?

Auto, 3.55s, stock stall. The OPs car needs cooling for sure, 140+ IATs is pretty hot.
 
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Shadow Grey 03

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Your shifting isn't all that quick either. That does make a difference. 623 wheel is more than enough to be running 130+ in that car. It will come with seat time.
 

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