44-Year-old Cobra Wins Street Car Challenge

[twobjshelbys]

Originally Posted by Wayne Maybury

I watched the entire show and just loved the outcome. I was somewhat worried about the 0-60-0 as the car did not have ABS nor did it have traction control. It still obliterated everything else that was supposed to be competing with it.

Several people have mentioned that the Cobra was modified. This was part of SEMA and of course the Cobra was modified as only modified cars were allowed to compete. The reason it did not do better in the show competition is because the car's appearance has not really been changed. Every car in that competition was very heavily modified, engines, drive trains, suspensions, exterior and interior designs, etc.

I thought that the Can-Am Boss 302 would do better than it did.

Wayne

I did notice the benefit of ABS: Those with them finished going in a straight line. The Cobra and several others fishtailed, and the Cobra did so quite a bit. Still stopped pretty fast though!

[Cobra #3170]

Originally Posted by twobjshelbys

I did notice the benefit of ABS: Those with them finished going in a straight line. The Cobra and several others fishtailed, and the Cobra did so quite a bit. Still stopped pretty fast though!

The Cobra fish tailed because it had a touch too much rear Bias. I set it up like that because we use left foot braking on the autox course and with power on, if it didn't have rear bias it would lock the fronts too soon. During the 0-60-0 I kept increasing the front bias on each run so that the last one is almost a straight stop. I plan on putting 315x30x18's on the front which should improve the stop quite a bit. You are right though, we made all our time in accelerating 0-60.
The Boss Mustang had some pretty bad tires on it (bias ply race tires that were very hard) he would have been much faster on modern tires.

[csx4910]

I would love to know what suspension mods and what engine you are running? I saw a referrence to it not being the original engine but no details as to what is in there now. An absolutely gorgeous car!!

[Cobra #3170]

Originally Posted by csx4910

I would love to know what suspension mods and what engine you are running? I saw a referrence to it not being the original engine but no details as to what is in there now. An absolutely gorgeous car!!

Thanks,
I'll give you the short version, engine is Shelby FE block, Blue Thunder raised port heads (it only needs 29 D. advance at peak power), MSD, Carrillo rods, Victor jr. manifold- highly modified, Ti Valves, 14.7 to 1, 1650 cfm Throttle body, seq. EFI really big roller cam, peak power 7600 peak torque 5500, headers are 2 1/8 primary 3.5 collectors. This engine has a Daley dry sump and Stefs tank and never leaks oil as long as it is running (13" of vacuum) CID = 498 with a Moldex billet crank. Engine by Kinetics in Michigan

The suspension is really where the car shines, the roll centers move together, it has 70% ackerman and a .5" front scrub radius so that turn in is very good and predictable. Front wheels are 18x10.5, rears are 18x11.5. Tires are 335 rears and 295 fronts. There is virtually no bump steer and minimal front anti dive geometry. Camber angles are -3.0 front and -2.0 rear, rear toe is -.185" total, front is - .060 total, wheel rates are in the 300 #/ " range, rear bar is 1", front is 1.25". Brakes are 12" Wilwoods with 4 pot Dynalites, I built jigs and fabricated the suspension from 4130 and then heat treated it. I use NMB rod ends (the best in my opinion) the shocks are Penske three ways with appropriate valving for my unsprung weight and spring rates. Wheels are Jongbloed pin drives. The frame is sleeved for stiffness in bending and torsion. It took about 5 years of tuning and tweaking to get it to handle like it does now. We went through 15 pairs of springs getting it to this point along with three shock revalvings. I can honestly say the car is really easy to drive now; it never does anything unexpected, unlike past incarnations. I have a 12 to 1 power steering gear that I made from an Appleton short track rack and the throttle has a very slow cam and cable system to help with modulation. The car was undriveable with standard linkage because it would blow the tires off when you gassed it. This throttle is so slow now that it is very easy to hold on the threshold of wheel spin at any time. Weight with all the extra junk is about 2370 with all fluids, rear wheel HP in the 670 range not as much as some but just right for this car. It actually feels like a modern car with no evil habits only it weighs a lot less than most and has more power than most too. It has a good combination for low speed handling, acceleration and track handling. Not perfect for any one event but pretty good for all events taken together.

[Anthony]

Originally Posted by Cobra #3170

Thanks,
I'll give you the short version, engine is Shelby FE block, Blue Thunder raised port heads (it only needs 29 D. advance at peak power), MSD, Carrillo rods, Victor jr. manifold- highly modified, Ti Valves, 14.7 to 1, 1650 cfm Throttle body, seq. EFI really big roller cam, peak power 7600 peak torque 5500, headers are 2 1/8 primary 3.5 collectors. This engine has a Daley dry sump and Stefs tank and never leaks oil as long as it is running (13" of vacuum) CID = 498 with a Moldex billet crank. Engine by Kinetics in Michigan

The suspension is really where the car shines, the roll centers move together, --------- It took about 5 years of tuning and tweaking to get it to handle like it does now. We went through 15 pairs of springs getting it to this point along with three shock revalvings. I can honestly say the car is really easy to drive now; it never does anything unexpected, unlike past incarnations. --------, rear wheel HP in the 670 range not as much as some but just right for this car. -----r.

HOLY MOL---DEX !!!!

Where else have you taken your car ?

Where else do you plan to take your car ?

Tell us a little about your co-driver.

You should take your car to Run-n-Gun and have some fun there.

[Cobra #3170]

Originally Posted by Anthony

HOLY MOL---DEX !!!!

Where else have you taken your car ?

Where else do you plan to take your car ?

Tell us a little about your co-driver.

You should take your car to Run-n-Gun and have some fun there.

The car just started to come around this last summer with the switch to 18" wheels. My suspension changes did not really improve the car that much until I went to 18 " rubber. I spent June, July and August tuning it up on autox courses and Oct. getting a set up for road race courses then developed a compromise for both. The first big event for the car was the Optima Challenge. This year I will probably track it at Buttonwillow (near Bakersfield Ca) and maybe Sears Point for SAAC if I can get the noise level down and I'll also run a bunch of local autox's.

Jim is the finest Autox driver I have ever seen, he is smooth and always fast no matter what vehicle he is in. He had not driven my car since 2004 when it was quite evil. With no practice at all he managed to blow everybody away in three laps on the autox at the Optima challenge. His first run would have won, then he just got faster on every run. The throttle had a little glitch in it off idle that I could not detect but he found it showing how sensitive he is. He did say that the handling was so good that he did not find anything that needed to be changed. The car is very easy to change now and we were prepared to move the rear bar up for the autox but left it alone, all we did was soften the front bar. Initially we were going to change the shocks for the 0-60-0 but the brake bias was so far off we did not have time to fix the shocks too.

Jim started the McKamey autox school and has won numerous national autox titles. We have been friends for 29 years after meeting when we were running against each other at a hill climb. Jim was almost killed there when he hit a tree on his last run trying to beat my time (I was faster in those days) his car was cut in half right behind his shoulders but all he got was a sore arm. We became good friends after that and have worked together on a number of autox car design ideas. He had many unorthodox ideas that lots of people laughed at including me but it turned out that he was right and all of us were wrong because they worked.

I really don't like towing it long distances anymore because it is a pain to do at my age and the only other person I would trust driving the tow vehicle is Jim Mckamey. Jim lives in Indiana and has plenty on his plate for this summer already, lots of the Optima guys want his help now,so run and gun is out of the question this year.

[Wayne Maybury]

#3170

Thanks for sharing your knowledge and experience with us.

Congratulations on seriously kicking butt. It was a joy to watch.

Wayne

[xlr8tr]

Love this story!! Can you explain what it was about the 18" rubber that made such a big difference?

Originally Posted by Cobra #3170

The car just started to come around this last summer with the switch to 18" wheels. My suspension changes did not really improve the car that much until I went to 18 " rubber. I spent June, July and August tuning it up on autox courses and Oct. getting a set up for road race courses then developed a compromise for both. The first big event for the car was the Optima Challenge. This year I will probably track it at Buttonwillow (near Bakersfield Ca) and maybe Sears Point for SAAC if I can get the noise level down and I'll also run a bunch of local autox's.

Jim is the finest Autox driver I have ever seen, he is smooth and always fast no matter what vehicle he is in. He had not driven my car since 2004 when it was quite evil. With no practice at all he managed to blow everybody away in three laps on the autox at the Optima challenge. His first run would have won, then he just got faster on every run. The throttle had a little glitch in it off idle that I could not detect but he found it showing how sensitive he is. He did say that the handling was so good that he did not find anything that needed to be changed. The car is very easy to change now and we were prepared to move the rear bar up for the autox but left it alone, all we did was soften the front bar. Initially we were going to change the shocks for the 0-60-0 but the brake bias was so far off we did not have time to fix the shocks too.

Jim started the McKamey autox school and has won numerous national autox titles. We have been friends for 29 years after meeting when we were running against each other at a hill climb. Jim was almost killed there when he hit a tree on his last run trying to beat my time (I was faster in those days) his car was cut in half right behind his shoulders but all he got was a sore arm. We became good friends after that and have worked together on a number of autox car design ideas. He had many unorthodox ideas that lots of people laughed at including me but it turned out that he was right and all of us were wrong because they worked.

I really don't like towing it long distances anymore because it is a pain to do at my age and the only other person I would trust driving the tow vehicle is Jim Mckamey. Jim lives in Indiana and has plenty on his plate for this summer already, lots of the Optima guys want his help now,so run and gun is out of the question this year.