Ok Dave, you were right....

HwyStar

Registered User

So, the times arent great, but man this car pulls. Hard. The fastest Ive gone on the track was a 12.36 @ 109 mph in the Lincoln. This felt a lot like that. Im sure when I get a shift light and the WOT box installed times should improve a lot. I got a new tune from Dalke, and put 2 gallons of C12 in. Ended up braking the axle when I let the air down in the radials to 20#. Before that, it just spun a lot. Man, this car didnt just have a pull to it, it would bury you in the seat, and the thing is it pulled all the way to the rev limiter. Usually, I have a good idea of when to shift by feel. But, this one wants to keep pulling.

https://youtu.be/HmHQ5M0fMfc
First run, it shows. Transmission popped out of gear when I let the clutch go. Man, that was embarrassing. I need to get used to the car still.

https://youtu.be/ABMnaIyQVfs
Second run.

https://youtu.be/t2iiSOqW0oI
Third run. This was a great race. It was a new 4 cylinder mustang in the left lane, he got me off the line, but I reeled him in maybe a hundred feet before the lights. Man that was close! My wife was fooling around with mounting the Go Pro. Took us a couple of tries to get it right.

https://youtu.be/RzuUUuf21kQ
This was when I broke the axle. It was just a light pop, and that was it. People were cool there. 5 guys helped me push the car back on the trailer. So, here I thought the engine would let go if anything happened!


Not sure where it broke yet, I have not got a chance to put it on the lift. I had a couple vehicles to work on first... I already have a set of chrome outer joints and a set of good Mark VIII axles on the shelf. So, if I use those chrome outers and Mark VIII shafts I should be good, right? You cant tell by my 60', I wasnt leaving that hard. If I could get down into the 1.8 60s that would do a lot for my ET. I was only dumping the clutch at 3000 rpm. Ive heard of people riding the clutch and brake at the same time on the line, but that seems like a awful lot to do when you already have a lot on your mind at the lights. Do I need to go with the improved inboard joints too? I was going to post the datalogs of the runs too, but Im having trouble with my SFTP right now, and the this website limit is 200k.....
 
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<a href="http://s48.photobucket.com/user/Windstarpro/media/IMAG0209_zpsiysrffrz.jpg.html" target="_blank"><img src="http://i48.photobucket.com/albums/f224/Windstarpro/IMAG0209_zpsiysrffrz.jpg" border="0" alt="fun stopper photo IMAG0209_zpsiysrffrz.jpg"/></a>

The fun stopper.
 
lol, like a hot knife through butter! I'm surprised your 60' times were so high, in the videos it seemed to get out of the hole quicker than that.
 
It's because I was leaving on the green. I was trying to figure on which yellow to leave. I think I will leave on second yellow next time. Bearing is 165k/miles old....:)
 
It's because I was leaving on the green. I was trying to figure on which yellow to leave. I think I will leave on second yellow next time. Bearing is 165k/miles old....:)

I've learned in my car to nail the gas as soon as the last yellow bulb lights up, pulls consistent 1.5 60' times (without red lighting) with a bias ply full Hoosier drag slick, 28/10.5/15 with 4.10 gears.
 
This makes me wonder what a full 1/4 pass would have been last year in my car. It ran (3) 8.90s back to back in the 1/8th and then it decided to act up at the shootout (alternator failure) looks like 13.70s would have been likely for it.



So, the times arent great, but man this car pulls. Hard. The fastest Ive gone on the track was a 12.36 @ 109 mph in the Lincoln. This felt a lot like that. Im sure when I get a shift light and the WOT box installed times should improve a lot. I got a new tune from Dalke, and put 2 gallons of C12 in. Ended up braking the axle when I let the air down in the radials to 20#. Before that, it just spun a lot. Man, this car didnt just have a pull to it, it would bury you in the seat, and the thing is it pulled all the way to the rev limiter. Usually, I have a good idea of when to shift by feel. But, this one wants to keep pulling.

https://youtu.be/HmHQ5M0fMfc
First run, it shows. Transmission popped out of gear when I let the clutch go. Man, that was embarrassing. I need to get used to the car still.

https://youtu.be/ABMnaIyQVfs
Second run.

https://youtu.be/t2iiSOqW0oI
Third run. This was a great race. It was a new 4 cylinder mustang in the left lane, he got me off the line, but I reeled him in maybe a hundred feet before the lights. Man that was close! My wife was fooling around with mounting the Go Pro. Took us a couple of tries to get it right.

https://youtu.be/RzuUUuf21kQ
This was when I broke the axle. It was just a light pop, and that was it. People were cool there. 5 guys helped me push the car back on the trailer. So, here I thought the engine would let go if anything happened!


Not sure where it broke yet, I have not got a chance to put it on the lift. I had a couple vehicles to work on first... I already have a set of chrome outer joints and a set of good Mark VIII axles on the shelf. So, if I use those chrome outers and Mark VIII shafts I should be good, right? You cant tell by my 60', I wasnt leaving that hard. If I could get down into the 1.8 60s that would do a lot for my ET. I was only dumping the clutch at 3000 rpm. Ive heard of people riding the clutch and brake at the same time on the line, but that seems like a awful lot to do when you already have a lot on your mind at the lights. Do I need to go with the improved inboard joints too? I was going to post the datalogs of the runs too, but Im having trouble with my SFTP right now, and the this website limit is 200k.....
 
I have about all the bolt typical bolt ons you can get. Was looking to just get back on the track so I could get motivated to work on the Mark VIII. But, this is taking a lot more time and money than I thought.
1990 XR7:
Stock bottom end
Stock heads aside from high spots cut down on in the bowl area and in the ports, no real porting other than that
SCP roller rockers shimmed and used comp cams SBC pushrods 7.9" I think...been a while
SCP Stage 2 cam
Kooks Mid Length Headers(man these headers look nice)
Just switched to metal catalysts
Flowmaster 50s(I think...)
60# injectors
255lph pump
85mm tb and MAF from SCP with cold air and divider
MPx with 10% pulley and 5% jackshaft pulley, stronger springs
Magnum Powers FMIC with the cool sounding fan and a pusher that I had on the shelf
Biscuit sized crank pulley
Taylor Thunderwhatever wires - these things are great, they are about 50 ohm/ft
Spec stage 2 clutch, shimmed the trans to .005" play on the input shaft
Mark VIII housing, with T-Lock with the Cobra Kevlar clutches 3.55 gear
Poly diff nose bushings and SCP rear diff mount with cool bat wing looking cover brace
Aluminum rear subframe bushings, all poly bushing replaces ments on the upper and lower control arms/ knuckles except the upper inner adjustable

Next would be the transmission crossmember. I can see that a lot of my wheel hop would come from the spongy trans mount, even with the poly body bushings, oh, and a better driveshaft.
 
The Spec SII clutch is your other problem. You'll probably continue to break parts until you get rid of that.

Trans cross member isn't going to help, as the problem is all after the diff, not before.
 
What would you suggest as a replacement? Is it because the clutch is grabby?

Yeah, the Spec clutch has, in my opinion, two issues. First, I do not like the friction material they use (Kevlar). Every single one I've taken out has generated extreme heat into the flywheel and PP. Most have wiped up liquid metal off the friction surface which in turn of course causes chatter and disc wear. While Kevlar is tough, it does not have good friction properties, IMO.

The other problem is that the Spec disc itself has almost no Marcel spring in it. This is why they are grabby or "on-off" feeling. This is a huge problem in an SC because you always have a lot of driveline slack to take up and most of it is in the IRS itself. Without give in the disc, smooth engagement is nearly impossible, and damage always results.

If you already have a SPEC clutch, I recommend taking it out and inspecting the friction surfaces. You will see what I mean about hot spots. If the PP itself is not damaged, then I suggest purchasing a CF DFII disc and putting it back together that way. The CF disc has a generous Marcel spring for stock like engagement, and it combines organic and metallic friction surfaces for good grip and less heat. The CF disc is about $150 or less and it will work fine with the SPEC PP. Otherwise, a new DFII is the only way to go on an SC (unless you want to go twin disc but that's a whole other thing!)
 




Is this what you are talking about? This is a CenterForce Clutch, Im not sure which model though. Think this will hold up to what Im shooting for? I took this out of the car I wrecked.
 
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