What a difference in aero in 50 years !

[hugh-guynes]

Good picture showing the difference in aerodynamic styling of two cars 50 years apart in age. The C6 Z06 has a Cd of .34 and the Tiger .45 . What stood to me was the windshield rake. The Tiger windshield looks like an airbrake ! Picture is a screen grab from a video at the 1/2 mile race last Oct. in French Lick IN.

[Mark and Nancy Petri]

Yes, you are out there shaming them [newer/more aerodynamic cars] with pure power:weight, always nice work out there 8)

Does your "high speed" (not shown here) chin spoiler improve the .45 any?

[hugh-guynes]

The front spoiler ( air dam ) certainly helped in the standing mile races . I have had more trouble with the back of the car getting light. In the Oct 1/2 mile I had to put on the rear deck with the spoiler . Concerning power to weight : my car is 4.25 pounds/HP , the Z06 ( 600 hp ) was around 5.1 pounds/HP . Better aero didn’t help , he couldn’t catch me. Later in the day I ran another Z06 with a reported 720 hp , so about the same power to weight as the Tiger . In that race I stayed close till second gear ( when the Corvette could get traction ) , then he just pulled away.

[Mark and Nancy Petri]

I thought that I remembered you saying that you had the power:weight edge on a stock Z06.
You’ve done a great job of "minimizing" the 50 year age difference with the upgrades to the powertrain & suspension, but seems like the Sunbeam factory sorta let you down with their lack of aero progress 🙄
In that 120+ mph range, I’m a little surprised that you don’t have more "issues" that need to be tamed.

What do you think "could" happen with something like your drivetrain in Tom’s GT2 chassis/body?

Thanks for posting.

[hugh-guynes]

Sorry if there was some confusion , here are some examples :
my Tiger 4.25 lbs./hp With only a 225/50 15 rear tire.
C6 Z06 6.2 lbs./hp
ZR1 Corvette 5.4 lbs./hp The Tiger and ZR1(stock) both do the 1/2 mile in 156-157 mph.
C7 Z06 6.16 lbs/hp Several videos on YouTube of these running 145-146 mph
Hellcat 6.29 lbs.hp Ran one twice that was 800hp ,won both times . At the last 1/2 race , Hellcats were pushing 1000 hp and running 175 mph.
Nissan GTR 7.1 to 7.3 lbs/hp varies by year . Good video on YouTube of me and a 2010 ? GTR we stayed even till around 100 mph then I pulled ahead. I also ran an Alpha 9 GTR ( 900hp ) two years ago . Not even close , he was much faster.

Both Tom and I both have our motors built by the same shop here in Cincinnati (Paul’s Automotive). Two very different motors though , Tom’s is a purpose built race motor that has to follow the SCCA rulebook. When I had my motor built I had two requests , that it could be street driven and run on pump gas. My motor is also much bigger (70+ cubic inches). A couple years back when Tom looked at my dyno graph ,his comment was if he had that much torque he would never lose.

[Mark and Nancy Petri]

Great stuff Hugh.
I was wondering if the GT2 body would be more aerodynamic (less like the proverbial brick) at those speeds… did sorta figure that without all the rigid "you must this/you can’t that" SCCA rules, your engine is "better". I suppose that Tom doesn’t see really high speeds on most tracks?

[hugh-guynes]

Bench racing is fun plus it doesn’t cost anything. So here is my guess. With Tom’s Gt2 body the Cd is certainly better than a stock Tiger ( Cd .45 ) but not as good as a C6 Z06 Corvette (Cd .34 ). Tom’s car weighs about 250 lbs. less than my Tiger and with my motor would have a power/weight ratio just under 4 lbs./hp . I have seen a Z06 with the same power to weight as my Tiger run a 173 mph 1/2 mile. I think with the right gear the GT2 body could run 167-168 mph in the 1/2 mile.

[Mark and Nancy Petri]

quote Hugh Guynes:

Bench racing is fun plus it doesn’t cost anything. So here is my guess. With Tom’s Gt2 body the Cd is certainly better than a stock Tiger ( Cd .45 ) but not as good as a C6 Z06 Corvette (Cd .34 ). Tom’s car weighs about 250 lbs. less than my Tiger and with my motor would have a power/weight ratio just under 4 lbs./hp . I have seen a Z06 with the same power to weight as my Tiger run a 173 mph 1/2 mile. I think with the right gear the GT2 body could run 167-168 mph in the 1/2 mile.

Yeah, that’s what I was trying to get to… I know Tom has those wide flares, but certainly no "near vertical" windshield!

Next thing you’ll be posting that Tom wants to trade his GT2 body for your monster motor 😯 🙄 😆

Thanks for the fun discussion.

[Author]

Posts