Test and tune results

[406shark]

Just got back from the track. It went pretty well... about what I was expecting/hoping for. Had the Caltrac's set the same as last season. Still running the 5 year old MT slicks.

Made 3 partial passes to test the 60 foot times and try and dial in the tire pressure.

First full pass came in at a 10.580 at 122.71 mph with a 1.451 60 foot time.
Second pass came in at a 10.562 at 125.33 mph with a 1.488 60 foot time.
Third full pass came in at a 10.563 at 125.43 mph with a 1.455 60 foot time.


The first full pass I ran into the rev limiter lowering the mph. The second and third pass the rpm ran into valve float at 7500 rpm. Way higher than the engine makes its power peak. The slicks are so hard that I had to keep lowering pressure down to 9 psi, and they still spun somewhat off the line and got squirrelly at the 1-2 shift.

Going to have to go with a larger diameter slick to get the rpm's down. Probably move to a 29.5 - 30" slick.

Here are a couple of videos showing the last two runs. My friend was having problems with my camera. He got most of the runs, but shut it off just before the et showed on the boards.



http://www.youtube.com/watch?v=use7CbUZrsY&feature=channel

http://www.youtube.com/watch?v=zHhqGXheKGM



Jeff

[spib]

hell ya, haulin ass and looking good, nice truck!!!!!!, cool vids:rock::rock:

[406shark]

hell ya, haulin ass and looking good, nice truck!!!!!!, cool vids:rock::rock:


Thanks. For some reason the first video is not coming up for me now? I guess I'll give it a little while and reload if it still isn't working.


Jeff

[dand355]

nice times congrats

[Diabolical]

Looks like you were tearing everyone up!
Great job and the truck looks killer!

[406shark]

Thanks guys. I can't wait for the muscle car shootout 2 weeks from tomorrow. They run it 2 or 3 times a season. It is index racing in 1/2 second increments. Originally they had 1/4 second increments, but didn't have enough cars to fill up. Now with the 1/2 second index you end up with a lot of sand baggers. Typically you have guys running in the .30 - .40's, or .70 - .80's dropping down to the .0 or .5 indexes and putting a fender on the other car.

I plan on running mine in the 10.5 index. We'll see after I get the new slicks what she'll run.


Jeff

[Diabolical]

Make sure your camera man gets the "Whole" vid :)

[406shark]

Make sure your camera man gets the "Whole" vid :)

Yeah, I gave him shit about it. He said he couldn't see the screen because of the sun. I told him he needs glasses. He also made a 3.5 minute video of the ground as he was walking around. :laughoutloud:
My daughter told me she would take videos next time. She thinks she is a professional.

I'd like to find a good deal on a small camera that I could mount on my cage for in car shots.


Jeff

[Diabolical]

I'd like to find a good deal on a small camera that I could mount on my cage for in car shots.

Jeff

I am getting ready to set up a section for members "In Car/Truck" vids..
I have been working on a aluminum mount for 1-5/8 and 1-3/4 bars with a
1/4-20 stud to mount a cheap camera to..
I think it will be really cool to see everyones runs..

I have bought digital cameras (8 to 10mp) off ebay for 30 bucks and they still work great!

[406shark]

I am getting ready to set up a section for members "In Car/Truck" vids..
I have been working on a aluminum mount for 1-5/8 and 1-3/4 bars with a
1/4-20 stud to mount a cheap camera to..
I think it will be really cool to see everyones runs..

I have bought digital cameras (8 to 10mp) off ebay for 30 bucks and they still work great!


Those are the same cameras I was looking at. Just have to take the time to come up with a mount system for it.

Jeff

[85ss]

Nice Jeff...
Glad it did what you were expecting and your happy with it...
Now the times can only get better...
Good luck bro...

[xten]

Way to go, Jeff! You'll be deep into the 10's in no time!

[406shark]

Thanks.

After talking to PTC today they recommended that I verify the rear gear ratio seeing as I didn't install the gears. They came with the truck, and the owner told me the gearing.

Today I went down to the shop and jacked up the rear and had one of the guys slowly turn the rear tire as I counted the drive shaft turns. Looks like it has steeper gears than I was led to believe. The drive shaft spun almost exactly 4.75 times for one revolution of the tires. Might explain why it was spinning up to 7500 rpm with the 28" tall slicks.

Looking through the Summit site it looks like it has 4.71 or 4.86 gears. Time for some 29.5" tall slicks...

I placed an order with Summit's Race Shop today for a fresh set of MT slicks, a window net, and a new seat belt harness setup. My old ones expired 4/10. They tend to look at you a little closer when you get into the 10's.

My friend that was running the video camera said that during my 3 trial passes to the 60' marker I was pulling the front tires up out of the lights about 10" on the last two. He said the front tires didn't turn until it was a ways out of the box. I had the 2 step only set at 4000 rpm on the first pass, then went to 4300 rpm on the next two passes. When I raised it to 4500 rpm and higher is was spinning the slicks too much to hook.

It should be interesting to see how she leaves with some new slicks on it. Not to mention it should pull all the way down the track in the power band. I can't wait.


Jeff

[85ss]

Awesome Jeff...
Are you gonna pull the gear to verify what it actually is or just go what it?
The taller tire should help you pretty good...
Good luck with it...
When's the next time out?

[406shark]

Awesome Jeff...
Are you gonna pull the gear to verify what it actually is or just go what it?
The taller tire should help you pretty good...
Good luck with it...
When's the next time out?


If it was a rear that I could pull the cover off I'd double check for an exact gear ratio, but it's such a pain to do on a 9". I've checked rear gear ratios with the tire/drive shaft method in the past and it always came out correct in the past, so I think I'm gonna call it good to go.

I really think the 29.5" tire is going to do wonders for my trucks performance.

Next time out is Sunday June 6th, there is a Muscle Car Shootout where they do index racing in 1/2 second increments. Looks like I'll be in the 10.5 second index. Should be pretty competitive.

I plan on getting some hopefully better videos.


Jeff

[Diabolical]

That sounds like a nice index class!
Why cant we have ANYTHING like that down here..
South Florida sucks for racers!

[85ss]

That sounds like a nice index class!
Why cant we have ANYTHING like that down here..
South Florida sucks for racers!

I wish our track done the heads up index's more often...
They used to do the .5 second index's from 5.50-8.00 (1/8)...
But now they only do 6.00 and 7.00 every 3rd weekend or something like that...
Real fun classes to run in...
Only thing I dont like is the pro tree...

[406shark]

That sounds like a nice index class!
Why cant we have ANYTHING like that down here..
South Florida sucks for racers!

It has become popular over the last few years. Started with once per season, then went to twice a year. This year they are having it 3 times this season. They originally started it with the idea of 1/4 second indexes, but didn't get many cars in any one of the classes so they went to 1/2 second groupings. I really like the idea of 1/4 second classes, but it's better than typical bracket racing. You don't have to sit at the tree waiting to leave for 3,4,5 or more seconds to leave.

I would think that if you talked to the owner of a track in your area and made a suggestion it might be well received? Here they call it a Muscle Car Shootout day. They don't limit it to only older cars. We usually have a least a couple of each of the new Challengers, Chargers, Camaros and Mustangs. Only American manufacturers allowed... except they do allow imports with American V8's as well.

You race others in your index until there is one. Then they pair off close index classes and continue until there is only one winner. You can win twice, once in your index, and one for the whole day. It the winners of the individual classes get a trophy, the winner of the whole thing gets a larger trophy and usually a gift certificate from a sponsor. Usually it's for a set of new slicks in any size you want.

I think I'd trade your weather for mine and you could have our race schedule. :laughoutloud:


Jeff

[dand355]

nice i have a simple cam corder mount in the truck havnt used it at the track but got some good vids of me hole shotting in my garage and running into stuff lol got to find the vid

[dand355]

oh yea mike they do have a muscle car shot out at pbir. dont know when but have to look on there web site for dates

[Diabolical]

Yeah.. But who wants to drive for 2 hours to race a bunch of sand baggers?
Most of those guys are able to run 8's and they bracket a 10.50 (1/4 mile at pbir)
ehhh.. I'll save my money and my bullets