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915 gearbox: Can you handle the truth ?

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Old 01-27-2017, 02:05 AM
  #61  
Amber Gramps
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Originally Posted by asifallasleep
Not sure how your boast about how fast you're driving that "cabriolet" as "intended", compared to how slow i'm driving my coupe relates to this discussion, a downshift is a still a downshift, no matter the speed. I wonder if you burned rubber on your way down the road. Boy, am I impressed. The amazing thing about these cars is how much fun they are no matter the speed.
Dude, enough with the pinky already

At least try to have some fun.

...and ya, it's just a cab.

A cab with a G-50 tranny so I really shouldn't be in the conversation, right? Tranny
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Old 01-27-2017, 10:16 AM
  #62  
asifallasleep
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Originally Posted by Amber Gramps
A cab with a G-50 tranny so I really shouldn't be in the conversation, right?
Finally you got something right, partially. Your car looks great btw.
Old 01-27-2017, 11:48 AM
  #63  
Drisump
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Originally Posted by Amber Gramps
Didn't intend to ruffle..... and obviously we are talking about two different driving scenarios. You drive your sports car in traffic where third gear is a mind numbing 40 mph... I drive mine as intended in box canyons and in the twisties where third gear hits the rev limiter at just under 80 mph with Butzi's full blessing. You come to a stop, I approach guys like you as a chicane in an otherwise straightforward course. Enjoy coming to a stop.
Hey Amber in third my 915 3.2 redlines at ....or just over 100mph, do you have a stock transmission? Admittedly my car is a Euro but I wasn't aware of dramatic gearing differences. When cruising around town not many people on this board would use every gear when decelerating but on the open twisty road, I agree that using the transmission in our cars is one of the fundimental, fun aspects of them. Personally,I think learning heal and toe is another cool skill to get the most out of these extraordinary cars but if an owner feels great joy in driving their car at more common speeds and effort...good on them. When I drive my car however, I try to extract the most fun out of her as possible (as opposed to driving my Land Cruiser). Fun for me is a sensible, enthusiastic pace with a critical attention to all aspects to my driving (similar to skiing)....shifting included. But hey, to each their own. Cheers
Old 01-27-2017, 11:54 AM
  #64  
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Originally Posted by asifallasleep
Finally you got something right, partially. Your car looks great btw.
I'm really trying hard to wrap my head around a situation where you would coast from 5th to 2nd and I think Donahue's example is about the only place. So ya, your method is fine, it just seems so counter intuitive. My G-50 pretty much lets me do whatever I want to do, short of cramming it into a gear that isn't spinning.

...and ya, you finally got something right too.....car looks great. Note the exposed T-bar ports...oh the huge manatee
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Old 01-27-2017, 12:01 PM
  #65  
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Just noticed that your car is a G-50 so I guess the gearing may be quite different. In third my 993 G-50 (6sp) seems to redline at about 80 mph as well. BTW the third/fourth shift in that tranny happens to be sublime. Cheers
Old 01-27-2017, 12:31 PM
  #66  
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I prefer the feel of a cable actuated clutch over a hydraulic one. You can feel the bite point of the clutch disc so much better in a 915, and it comes in at a good, low point so that you can feather it in, and roll on the gas after it bites. When I took my clutch out at 350K miles, and changed the throwout bearing, the clutch looked new, and so did the flywheel. I ended up changing everything anyway, and gave away the clutch. It's still working on my friend's 911SC.

And the Wevo shifter is fantastic. Love the feel of it with the Wevo PSJ.
Old 01-27-2017, 02:22 PM
  #67  
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Originally Posted by Drisump
Just noticed that your car is a G-50 so I guess the gearing may be quite different. In third my 993 G-50 (6sp) seems to redline at about 80 mph as well. BTW the third/fourth shift in that tranny happens to be sublime. Cheers
No, you are right...brain fart on my part. It's gotta be 2nd gear redlines at 80mph. It's something like 40-80-110-125-and I chicken out at about 145 in 5th.

Rusnak, you are not alone in your clutch preference. Imagine how insane it was managing the solid linkage clutch on the '64 Barracuda I built in 1985-86. Step on the gas enough to torque over the 318 and the clutch would let itself out. It was on or off...there were no other choices.
Old 01-27-2017, 02:53 PM
  #68  
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You know, it would be interesting to post the shift points from the owner's manuals of a 915 and G-50 car, side by side. That would give some indication of gear ratios. The SC 915 is geared so that the engine revs are close to 1000 rpm higher at the same given speed. When I drove my '84 home, I was shocked at how much more torque it had, and at much lower RPM. It also felt much heavier, but the suspension settings were like night and day compared to how my SC was set up. The '84 felt like a rocket sled on rails, and the '78 like a tippy peaky 10-speed bicycle.

When I was test driving the '11 Cayman, I was wondering why 5th was only getting me around 85 mph at just over 4,000 RPM. Then I looked at the gearshift and it was like "oh, there's a 6th gear. Nice."
Old 01-27-2017, 04:03 PM
  #69  
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Originally Posted by rusnak
You know, it would be interesting to post the shift points from the owner's manuals of a 915 and G-50 car, side by side. That would give some indication of gear ratios. The SC 915 is geared so that the engine revs are close to 1000 rpm higher at the same given speed. When I drove my '84 home, I was shocked at how much more torque it had, and at much lower RPM. It also felt much heavier, but the suspension settings were like night and day compared to how my SC was set up. The '84 felt like a rocket sled on rails, and the '78 like a tippy peaky 10-speed bicycle.

When I was test driving the '11 Cayman, I was wondering why 5th was only getting me around 85 mph at just over 4,000 RPM. Then I looked at the gearshift and it was like "oh, there's a 6th gear. Nice."
You know the story of the LS7/968 I finished up for a fellow Rennlister. I was going 150 when she ran out of fuel flow/pressure totally unaware it had a sixth gear. I had spent months on big brakes, all new bushings and axles, sway bars, engine cooling and electrical and never once looked at the shifter.

My car has a nice 3,000 RPM freeway cruising speed of right at 80 MPH where the Bisimoto Pulse Chamber does not drone and when cruising the car is almost silent.
Old 01-27-2017, 06:34 PM
  #70  
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Originally Posted by asifallasleep
Finally you got something right, partially. Your car looks great btw.
Oh Lord, now you've done it. Don't look at Amber in the eye, don't feed Amber and whatever you do...don't compliment Amber!

Sorry Dougie, had to give you a hard time...it has been years.
Old 01-27-2017, 07:08 PM
  #71  
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Mine is 70-ish at 3000.
Old 01-27-2017, 08:21 PM
  #72  
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Originally Posted by salukijac
Oh Lord, now you've done it. Don't look at Amber in the eye, don't feed Amber and whatever you do...don't compliment Amber!

Sorry Dougie, had to give you a hard time...it has been years.
I thought it was no snacks after midnight? Or was that the other guy?

And Doug, what do you mean, ran out of fuel pressure? This was a resto job, or???
Old 01-27-2017, 10:13 PM
  #73  
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Originally Posted by rusnak
I thought it was no snacks after midnight? Or was that the other guy?

And Doug, what do you mean, ran out of fuel pressure? This was a resto job, or???
This is Odurandino's LS7 block/LS3 head, stroked (something like 384 Cu In small block chevy) crammed into a '95 968 that was still running the 968 fuel pump. For some reason the 044 motorsports fuel pump wasn't included in the initial build. The little fuel pump intended to feed a four cylinder could not keep up with the demand. It would always lean out and heat up at about 500 HP. I could do burnouts forever with it's stage 3 clutch and 928 gears.....Car is safely tucked away in Boston for the winter.

Originally Posted by salukijac
Oh Lord, now you've done it. Don't look at Amber in the eye, don't feed Amber and whatever you do...don't compliment Amber!

Sorry Dougie, had to give you a hard time...it has been years.
Bring it!
Old 01-28-2017, 11:38 AM
  #74  
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Originally Posted by Steve Weiner-Rennsport Systems
A 915 is an excellent shifting transmission when everything is right.
Certainly it is. The problem is, 915 transmissions rarely have everything right. I've had two '86 915 cars and now an '88 G50. Both 915s were set up very nicely and the cars were great fun. But as good as the 915 can be, the G50 is a step up in terms of shifting action, and I prefer the hydraulic clutch. I agree that one should choose the better car overall and not fixate on 915 vs. G50, but if two similar cars are being considered, the G50 one definitely gets the edge.
Old 01-28-2017, 11:42 AM
  #75  
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Originally Posted by rusnak
You know, it would be interesting to post the shift points from the owner's manuals of a 915 and G-50 car, side by side. That would give some indication of gear ratios.
Just remember that the 915 has either a 7:31 or 8:31 final drive ratio, whereas the G50 is a 9:31.


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