CSX3170 repair and autox results
 

I have just returned from being on the road for two weeks, Scott and I left for Provo, Utah on Sunday the 25th of August. We got to the new Kirkham facility on Monday morning to repair the damaged LH rear differential mount. We found such extensive damage to the mount and cross member that David Kirkham recommended replacing the entire cage structure and cross member rather than try and patch the old metal. This was an enormous job that could only have been done at Kirkham. I won't go into all the details but all rear suspension, floors, trunk, differential, back panel, dry sump tank and battery as well as the rear upper trunk panel had to be removed. Scott and I worked (4) 14 hour days and on Friday 5 more hours along with all the Kirkham people getting the car fixed. It is now better than new thanks to Kirkham Motorsports and their expertise. We drove all night from Kirkham to the CAM invitational at Lincoln Nebraska. Scott finished second on Saturday after getting only 2 hours of sleep and the car only had a quick garage floor alignment. He only lost by .195 to a 2017 Corvette, so not too bad. Sunday it rained and we elected not to run because David Kirkham had us clean the bottom of the car to a spotless condition prior to final repair and we did not want to clean it again. We elected to take it to a local alignment shop and finish the alignment process. We found the rear toe was off a considerable amount which would probably have put Scott in first on Saturday. It rained again on Tuesday so CSX3170 stayed in the trailer and we withdrew from the National competition. Wednesday we left for Colorado and the Goodguys event. We got there Thursday and set up for Friday morning competition.
The people in Colorado were great and we got tons of runs. The course was the smallest and tightest we have ever been on as you can see from the video. The car ran perfectly all day Friday and Saturday and won both the pro class and the shootout. Scott was his usual precise self running a string of 32 second times against some very good competition. Grey65 was there and doing very well with his new set up along with (2) tube frame racing Corvettes with Warren Johnson LS engines. Scott was the only car in the 32 second range all others were 33 and up. All and all the new set up is better than ever and we have a couple more up grades before Scottsdale. Grey65 is on the video right after 3170.
The new Kirkham facility will be world class when complete and their capabilities are already second to none. Thanks again to David, Dave and all the gang at Kirkham!

https://m.youtube.com/watch?v=LaMSpl..._SskaA&index=2

Awesome!!! We were in CO last week but left on Thursday. I would have loved to been able to stick around and see you at the Good Guys!

Wow, that was a lot of work to get CSX3170 back into competition condition! Nice run and good luck with the rest of the season.

Holy cow what a tight course. About like changing clothes in a phone booth.. Looks like Scott handled it with no issues, though.

Bob

Very impressive all around.
Don't think I've ever seen that tight of a course. Short too.

That is really great and it is good that you were able to get the Cobra repaired and done right. Now you shouldn't have anything to worry about like you may have had if you had just patched it up Congratulations on the runs as they were very good.

Ron

I probably missed it in another thread, but how did the damage happen? Sounds like a bi more than wear and tear!

Damage
 

The differential challenged the 53 year old mounting cage and won. It tore the LH rear mount out of the cage structure then cracked the front mount at the cross member. It then beat up on the holes in the cage by banging the U joints against them and tearing up the clearance holes and the U joint flanges. The new 4.88 rear gear can provide up to 3000 lb/ft to each half shaft in low gear.
Kirkham parts are identical in outside dimension but heavier gauge and better material. We replaced ha;f shafts and U joints too, and installed 160,000 psi bolts.

What a great video, thank you. You mean Shelby didn't anticipate these cars still being raced over 50 years later? I admire you for running your car the way you do.

Thanks for the updates. See you at the Good Guys in Scottsdale. Always enjoy videos, keep em coming!

Thank You
 

Here is the in car, Scott just sent it to me. Peak speed only 56 mph but tight course. We used a pretty aggressive slope on the traction control because the surface was slippery so the engine is not as aggressive sounding.

https://www.youtube.com/watch?v=YiNSZQSt9iQ

Funny, "traction control" is not usually heard in conjunction with an original Cobra...I LOVE it!

Assume you were in CAMs class. How much does your car weigh? I believe 2500 is minimum w/o driver.

3170 weight
 

The car weighs 2370 pounds because of the dry sump and fuel injection add on's. I added 180 pounds with gaffer shot bags before we left Utah. We weighed in at tech at 2630 pounds before running on Saturday. We left the weight in the car for GoodGuys because it is actually faster with weight on 200 TW tires. If we were on Hoosiers I would remove the weight. The tread rubber is hard enough that we loose mechanical grip (deforming for irregularities in pavement) due to reduced weight faster than we increase cornering force from the reduced weight. There are structural problems with adding much more weight than 150 pounds though. The Corvette boys have been crying ever since they allowed Cobras to run at 2250 so SCCA increased our minimum to 2500. They have let modified 2018 Corvettes in now with stability control, ABS ect, ect, and they are still crying. The guys that cry the most are all back markers but they make lots of noise on social media. Hopefully the crying will slow down now that we got our a$$es kicked at nationals. We have run several back to back tests with and with out the weight it is always faster with the weight. I actually added more weight this year and it did some damage so I only add 150 lbs now. I should clarify we had about 12 gallons of fuel and extra shot bags during the invitational. I removed two shot bags so were were closer to 2560 or so after that with about 5 gallons of fuel.

Thanks!

I'd like to run CAMs too but my car is under 2100#. I don't see how to add that much lead safely.

I may run unballasted in E mod or possibly with about some ballast in XP.

So far I am just trying to get the car down to the ride height it was designed for after one of the PO raised it to clear very wide tires and wrong offset in the wheels which apparenlty caused the fenders to ground on the tires.

I got it running pretty well now and have installed my kirdey seats.

I'll get there.

Weight
 

Boy that is really a lot of weight to add. It is too bad that the SCCA did not investigate the issue prior to changing the rule. I have looked at both X and emod but decided my car would not be competitive in either. The Cam class was a place for people like us to run supposedly free of SCCA politics. Once again the desire to get more entrants in the class has resulted in rules tailored to high volume cars. Adding 400 pounds would be very difficult and probably unsafe. You might make it work in X prepared with a high reving small block,
huge tires and good geometry. The RX7 cars are tough in that class, about 400 hp with turbo rotaries but a 600 horse small block might do it. Emod would be impossible, Kiesel dominates there with a light weight sprite and turbo rotary power with an even faster car coming next year.

Well, the truth is that I sold a nine times national (including 2018) champion Lotus 7 and bought this cobra. I am not a national champion level driver but with a competitive machine I can still beat some of the young guys now and then.

I want to make my cobra a good car for autocrossing but still be streetable.
So I do want to be legal in some class without ruining the car.

Sounds like you are having fun!