SAAC-30 California Speedway
- Thread starter Bill G.
- Start date
Ron McCall
Supporter
Awesome pics John!!!! Thanks for sharing. Is that a -1 ZF?
What ring and pinion are you using?
Can you tell me about your clutch set up ?
Thanks!
Ron
What ring and pinion are you using?
Can you tell me about your clutch set up ?
Thanks!
Ron
ZF & Clutch
Ron:
You get a gold star for spotting the early -1 ZF!!!!! Yes, it is the infamous 1st gen ZF with all of it's problems. It is actually the orginal which came with this car. I am searching for a later model ZF to race with, so that I can put this one is storage. This trans is certainly the Achellies heel of the car. The exposed shifter input needs cleaning and lubing after every event.
I was running the car with a 4.22 ratio ring and pinion but broke that set at Limerock last month. I just replaced it with a 3.40 set to run Sebring and Daytona.
I'm not sure of the correct term for the clutch, but it is the special type with the teeth around it. I'm acutally meeting with my maintenance team tomorrow and will have more info on the clutch. (As you might tell, I'm not the mechanic, nor would I pretend to be!). I do know the clutch is a heavy duty racing clutch and hydraulicly activated. More to follow.
John
Ron:
You get a gold star for spotting the early -1 ZF!!!!! Yes, it is the infamous 1st gen ZF with all of it's problems. It is actually the orginal which came with this car. I am searching for a later model ZF to race with, so that I can put this one is storage. This trans is certainly the Achellies heel of the car. The exposed shifter input needs cleaning and lubing after every event.
I was running the car with a 4.22 ratio ring and pinion but broke that set at Limerock last month. I just replaced it with a 3.40 set to run Sebring and Daytona.
I'm not sure of the correct term for the clutch, but it is the special type with the teeth around it. I'm acutally meeting with my maintenance team tomorrow and will have more info on the clutch. (As you might tell, I'm not the mechanic, nor would I pretend to be!). I do know the clutch is a heavy duty racing clutch and hydraulicly activated. More to follow.
John
Attachments
GT40 Airborne????
Gary & Len:
Just got these pix of the GT40 at Limerock. We cranked up the rear spoiler to the max for this event, and really got the feel of the fronts. Here's a picture of the car cresting the uphill. Probably 105-110 MPH. I'll take any amount of downforce I can get right about now!!! /ubbthreads/images/graemlins/shocked.gif
Gary & Len:
Just got these pix of the GT40 at Limerock. We cranked up the rear spoiler to the max for this event, and really got the feel of the fronts. Here's a picture of the car cresting the uphill. Probably 105-110 MPH. I'll take any amount of downforce I can get right about now!!! /ubbthreads/images/graemlins/shocked.gif
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Re: GT350 under braking
Great pics. Definitely suck up the seat leather on that one!
Great pics. Definitely suck up the seat leather on that one!
Ron McCall
Supporter
Re: GT350 under braking
John,
Your car is incredible! I just got my ZF today from Pantera Performance.If you are looking for one I would highly recommend that you give Dennis a call.He did an outstanding job on mine and the price was right as well.
Ron
John,
Your car is incredible! I just got my ZF today from Pantera Performance.If you are looking for one I would highly recommend that you give Dennis a call.He did an outstanding job on mine and the price was right as well.
Ron
John,
Will you give up acceleration out of the corners with the 3:40 as opposed to your 4:22 ratio, just to gain a higher top end speed? What is is your assesment of that? I have noticed in other post that you are rebuilding the ZF transaxle and that you feel that it is a week link in the performance of you car. As I understand there was a special version of the ZF built for John Wyer for Le Mans races. The road cars received something else. Besides the reference that given to you on this Forum (for the Guy in Colorado that does Panateras) as for a source for your rebuild, there is RBT in California that builds a American version of the GT40 ZF in California. I don't know if it is strong enough for a race car GT40 or if it will meet FIA vintage standards, but it may be another source. Thanks for the photo post, as allways the GT40 looks great with the new exterior additions. Hope to see you in future HSR scheduled races.
Len
Will you give up acceleration out of the corners with the 3:40 as opposed to your 4:22 ratio, just to gain a higher top end speed? What is is your assesment of that? I have noticed in other post that you are rebuilding the ZF transaxle and that you feel that it is a week link in the performance of you car. As I understand there was a special version of the ZF built for John Wyer for Le Mans races. The road cars received something else. Besides the reference that given to you on this Forum (for the Guy in Colorado that does Panateras) as for a source for your rebuild, there is RBT in California that builds a American version of the GT40 ZF in California. I don't know if it is strong enough for a race car GT40 or if it will meet FIA vintage standards, but it may be another source. Thanks for the photo post, as allways the GT40 looks great with the new exterior additions. Hope to see you in future HSR scheduled races.
Len
Len:
Just completed the HSR Event at Sebring with the GT40. The new gear ratio is steep, but I still managed a first place in class. As for your observations...I found myself in 1 gear lower than usual to get the jump out of the corners. I can still out accelerate most of the cars in my class (mainly chevrons & lola sports racers). I could not attain anywhere near top speed at Sebring. Even on the long back straight. I would enter the straight in 2nd, and shift up to 3rd, 4th, and just as I would shift up into 5th it was time to get on the brakes and start downshifting.
Through the long turn 17 sweeper onto the front straight, I'd down shift to 2nd, which set up a very nice run down the front straight upto 4th.
I'll be running Daytona in a couple of weeks, that's where the gearing will truly shine. Without topend speed, you don't have a chance there. I know of some guys in Lolas who claim to be breaking 200mph at Daytona. I don't think I have the balls to take a 40 year old, $million+, car up to that speed, but I do expect to be competitive!
Just completed the HSR Event at Sebring with the GT40. The new gear ratio is steep, but I still managed a first place in class. As for your observations...I found myself in 1 gear lower than usual to get the jump out of the corners. I can still out accelerate most of the cars in my class (mainly chevrons & lola sports racers). I could not attain anywhere near top speed at Sebring. Even on the long back straight. I would enter the straight in 2nd, and shift up to 3rd, 4th, and just as I would shift up into 5th it was time to get on the brakes and start downshifting.
Through the long turn 17 sweeper onto the front straight, I'd down shift to 2nd, which set up a very nice run down the front straight upto 4th.
I'll be running Daytona in a couple of weeks, that's where the gearing will truly shine. Without topend speed, you don't have a chance there. I know of some guys in Lolas who claim to be breaking 200mph at Daytona. I don't think I have the balls to take a 40 year old, $million+, car up to that speed, but I do expect to be competitive!
John,
I will not be making the Daytona event but it sounds as if you have the new gear ratio situation resolved. Just use lower gears to copensate for the higher final drive. Is it true that you have to dound shift the ZF in sequence from 5th to 4th to 3rd to 2nd to 1st with out skip shifting from fith to second etc?
No dought that you will achive 5th gear on the fast straight at Daytona. Do you think you will reach 185MPH or so? I hear you about taking 1043 to 200MPH plus as the Lola Spider's (Sports racers) claim. Have a very fun and safe race.
Just as an aside, are your Westlake Gurney heads aluminum? And are they stamped with a serial number that tie them to a build date? The reason I ask is there is a guy in the state of Maine that claims that he bought all of Dan Gurney's inventory in California and is selling original 1960's Gurney - Westlake heads. If this guy is for real, i will give you his contact number if you should need parts for 1043.
Best wishes
Len
I will not be making the Daytona event but it sounds as if you have the new gear ratio situation resolved. Just use lower gears to copensate for the higher final drive. Is it true that you have to dound shift the ZF in sequence from 5th to 4th to 3rd to 2nd to 1st with out skip shifting from fith to second etc?
No dought that you will achive 5th gear on the fast straight at Daytona. Do you think you will reach 185MPH or so? I hear you about taking 1043 to 200MPH plus as the Lola Spider's (Sports racers) claim. Have a very fun and safe race.
Just as an aside, are your Westlake Gurney heads aluminum? And are they stamped with a serial number that tie them to a build date? The reason I ask is there is a guy in the state of Maine that claims that he bought all of Dan Gurney's inventory in California and is selling original 1960's Gurney - Westlake heads. If this guy is for real, i will give you his contact number if you should need parts for 1043.
Best wishes
Len
Hi "A"
You question about ZFs with sequential shifting was true of some units but I do not have any first hand information. However, the label worn on those cars is in the attached picture. This label will also create a lot of interesting comments at car shows and it will convenience the valet service to just leave your car parked in front of the restaurant until you get back.
You question about ZFs with sequential shifting was true of some units but I do not have any first hand information. However, the label worn on those cars is in the attached picture. This label will also create a lot of interesting comments at car shows and it will convenience the valet service to just leave your car parked in front of the restaurant until you get back.
Attachments
Hi Len,
Just like many others, I bought a new ZF from RBT. The shift pattern is like in this picture from a Pantera. Note that reverse is slightly off to the side and is not directly aligned with 1st. This is the normal shift pattern with no sequential stuff.
I went with a new ZF because I could select the gear ratios, LSD was standard, and it was easy to add a trans cooler if ever required.
My car is mostly for the street with occasional track days so I picked ratios that would let me get to 61 mph in first for killer 0-60 times and be under 2,000 rpm at 75mph in 5th for quite highway cruising. The other gears give me about a 2,000 rpm drop at each redline shift. All in all a lot like your Ford GT.
Good luck with your projects, post pictures when you got them.
Just like many others, I bought a new ZF from RBT. The shift pattern is like in this picture from a Pantera. Note that reverse is slightly off to the side and is not directly aligned with 1st. This is the normal shift pattern with no sequential stuff.
I went with a new ZF because I could select the gear ratios, LSD was standard, and it was easy to add a trans cooler if ever required.
My car is mostly for the street with occasional track days so I picked ratios that would let me get to 61 mph in first for killer 0-60 times and be under 2,000 rpm at 75mph in 5th for quite highway cruising. The other gears give me about a 2,000 rpm drop at each redline shift. All in all a lot like your Ford GT.
Good luck with your projects, post pictures when you got them.
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Sounds like my gears exactly.
