New 1/4 mile time

[Excaliber]

I suspect trap speed is also affected by traction IF your still trying to 'hook up' in 2nd or even 3rd! The local BDR here could not hook up until well into 3rd, 1st and 2nd were a joke (he's running TA's). The calculator assumes traction is not a major issue...

[DavidNJ]

He had a 2.0 60'. That doesn't sound so bad. And, we are talking about less than 300rwhp.

[Excaliber]

Come to think of it, I recall Dennis said last year his BDR was spinning ONE tire real bad with the open rear...

I would assume thats the same thing going on here.

[jeff priest]

The e. t. calculater assumes ideal conditions { good temp. and low humidity} along with no wheel spin. In a real world application you should expect your e.t. to be slower by a second ... maybe even more depending on wheel spin, shifting etc. I just like to use the calculater as a what if . Also I thought Dennis posted that he was making 298 hp at the wheels, and I heard some where that the BDR Cobras weigh somewhere around 2400 lbs.

[Dennis Kelley]

Yes the car is doing the one wheel peel. I have a new diff and tires on the way. The car did dyno at 289rwhp. When I made the 12.91 run I had to completely lift off throttle in second gear. I think that is why the mph is low.

later

Dennis

[FUNFER2]

Last year, I had a Pro-5 driver test my cobra at Scribner Raceway. !0" Hoosier slicks. After 5 attempts, we got it dialed in. Best was 10.38 @ 134 mph. Chuck Spanal dynoed the motor 3 years ago. 570 hp at the flywheel. On the chassis dyno, it was 534 rwhp., after a lot of tunning. I'm very happy with it now. Can't wait for "Americruise" coming up.

[Excaliber]

Something I've noticed with the Drag Race Calculators. The more horse power a COBRA has the further away from the 'numbers' of reality vs software become.

With Dennis' BDR at 289 rwhp the calcs are within reason, especially when you consider the 'one wheel peel'. Try running a 500-600 plus horse Cobra and the numbers get further apart. Most calcs will say a 600 horse car, say 2800 pounds, will be in the 9's. Darn FEW Cobras actually are. Rare to even get in the 10's in reality, regardless of horse power.

Funfer2, that bad boy rocks. SLICKS make the difference!

OH, and are these calculators looking at CRANK SHAFT horse or REAR WHEEL horse? They never say.

[Burnd]

Originally Posted by FUNFER2

Best was 10.38 @ 134 mph. Chuck Spanal dynoed the motor 3 years ago.

Thats "unusually" quick for a typical Cobra chassis, especially if it has a light curb weight. Impressive ET's like that can be had with half the HP in a high spinning SB (i.e., KC couldn't break 10.5 in a 700+HP Kirkam cause they couldn't get it to the road); it's the weight distribution, suspension and gears that are the trick. I'm curious; what were the 60 fts? What does the car weigh wet? What is the wheel base spread on a Lone Star? Approximately what per cent of the block is set back over the front axles (10%, 20%, 40%, etc) or do you know the weight forward/rear weight distribution? What rear gears? Is it adjustable coil overs and shocks for ride heigth & shock dial in?

The weight transfer on launch AND "holding it" between 1st & 2nd gear would have to be optimum to maintain hookup for that kind of an ET. Either the motor is setback or somebody did an "exceptional" job on that suspension for you. If I was in your shoes; I would be a lot more than just "happy" with that rig. I'd be "thrilled". You can "eat" just about anything that shows up on the street with that machine. Congrats..... that's impressive. I'm jealous..... (temporarily).

Bernie

[FUNFER2]

Excaliber- I agree with you. Using the calculations or even the desk dyno, we have found on the chassis dyno that there can be many.... variables. The only correct & useful way is the chassis dyno to get real world numbers, especially the new "Mustang dyno". Yes, slicks make a huge difference ! On street tires I believe the time was around 10.90. For guy's using street tires, try spraying a degreaser on the tires, let it stay on for a while then, dump hot water on them. It softens them up. We do this on the sprint car tires & they feel brand new. But remember, do this on soft dirt tires. Don't know if it will help with hard compound street tires. I had Chuck dial in the motor on his dyno then we ran it on the chassis dyno.
Burnd- "We had a Ford club day". Most everyone was impressed with the times. Really, the only guy that was not impressed had a Pro-Street Galaxy with a 8-71 saying it had well over 1,000 hp. He looked at my cobra & smiled shaking his head. Well, after my last run, I couldn't find him....hum ? LOL ! Maybe it's because I kicked his @ss ? He ran a 10.65 (I think) Good time for a heavy sled. I agree with you on the small block but, I had to have a so called "Cobra Motor" We all had better watch the rice burners. 4-cylinder, basically stock, big turbo, coolers & methanol injection bring BIG hp. ! STOCK ! Ah, but there's nothing better than hearing a American V-8, big or small. The 60ft, if I remember correctly was 1.8. Had to slip the clutch for traction. On the second run, he dumped the clutch, front end came off the ground apx. 15" and shifting into second while in the air. Man........that was so,ooooo cool ! But, when he came down, the left ball joint broke, bending the wheel & sending him into the next lane, just missing the cone. Yes, I was a TAD....nervous. Trying to explain the different chassis set up's, gearing, tire psi, shock settings, shifting points ect.....would take too much typing. (I'm one of those two finger guy's) hehe!
But, here's the basics. Car weighs 2,390 lbs. with 18 gallons of racing fuel and my fat @ss in it. Home made short open header pipes, four inch tubbing down to three inch with turn out's. (good for torque) Adjustible coil overs, 350 front, 220 rear. I made new four bars out of alum. 550 lb. of torque twist. Just like our sprint car. The rear really squats at launch. With 8 psi in the slicks, I'm glad I used bead locks ! Wheel base is 94". In about two weeks, I found a guy that races' I.M.C.A Modifieds with electronic scales. He's coming over to my shop so I can set (or try) up his car, he's way to tight. Then I'll scale mine. I did move the motor back 3.5" The center line from the axle to the center of the carb. 21". From the axle to the front of the water pump is apx. 4". If you look in my gallery, you'll see that I have a lot of room in front of the engine. The weight transfer is great especially being a big blk. I use a modified TKO tranny, (I live outside the city by a highway so the overdrive is needed) 9" Ford with a Currie locker pumkin. Most of the time I use 331 gears. Much higher, 1st gear is useless. Thanks for the kind words. Sounds like you've got plans, what are they ? By the way, I can't run a sanctioned NHRA/IHRA race, no full cage roll bar. I should anyway but.........