928 Estate decision time...5 speed conversion or stay auto?
11-08-2010, 07:52 PM
#32
Rennlist Member
Wow, what a relevation. I always thought is was a simple as Porsche syncros=bad, BW=good. I had been planning to eventually replace mine, but perhaps I should think more about reparing it.
11-08-2010, 08:03 PM
#33
Rennlist Member
Greg, when mark was running speedvision with his 928,it had 420rwhp and he was running 1:40.1 on DOTs. I run 1:36.1 on DOTs. with the track maybe being 1 second faster. now, he has 150hp more and most all of what he is doing now, is power and cornering based due to slicks. He has slicks, which is worth about 2 seconds a lap min vs my garbage can tires. our last times in the dry at laguna, he ran 1:31s and I ran 1:36s. thats 5 seconds. 3 of which are due to power and braking as well as weight. in the end, there is not a hill bit of difference between what mark is doing and what I am doing as far as a transmission wear on the synchros, however, certainly, his extra 150hp has to add even more heat to the gear box, and that could be what you are talking about. BUT, we are not talking about a Joe Fan or Anderson car, we are talking my car or lesser versions. by the way, you and I both know with even 420rwhp, i would have no issues as well!
There would be no song to be sung. a shift is a shift. either you do it right , or you break things and blame the equipment or pay for new stuff because you are just driving "flat out".
Nothing with my car is special, its not an exception, i drive the car as it is meant to be driven, but I am also a student of the sport and have always learned how to go faster and also be easier on the equipment. There is no more force on a synchro with 500wrhp vs my 370rwhp. (5th gear, yes, gears, yes) the difference is in matching the gears. you dont think Im hustling around the track, take a look at my shifts, my blips and shift times.
Unfortunately, many of the "rule" folk, tend to discount the most important rule of racing. use the equipment how it is designed to be used. break that rule, and things break. So, am I the exception, in racing, I could be, but there are others out there that make things last too and go fast. But, there are more of the type that drive fast and break things. Just the way things are.
There would be no song to be sung. a shift is a shift. either you do it right , or you break things and blame the equipment or pay for new stuff because you are just driving "flat out".
Nothing with my car is special, its not an exception, i drive the car as it is meant to be driven, but I am also a student of the sport and have always learned how to go faster and also be easier on the equipment. There is no more force on a synchro with 500wrhp vs my 370rwhp. (5th gear, yes, gears, yes) the difference is in matching the gears. you dont think Im hustling around the track, take a look at my shifts, my blips and shift times.
Unfortunately, many of the "rule" folk, tend to discount the most important rule of racing. use the equipment how it is designed to be used. break that rule, and things break. So, am I the exception, in racing, I could be, but there are others out there that make things last too and go fast. But, there are more of the type that drive fast and break things. Just the way things are.
Mark:
BTW...I treat virtually everything that happens with your car as the "exception", not the rule. If you were to try and find the 6-7 seconds per lap difference between your times and Anderson's times....you'd be singing a completely different song. Making up 6-7 seconds a lap is an eternity, on the race track.
BTW...I treat virtually everything that happens with your car as the "exception", not the rule. If you were to try and find the 6-7 seconds per lap difference between your times and Anderson's times....you'd be singing a completely different song. Making up 6-7 seconds a lap is an eternity, on the race track.
11-08-2010, 09:05 PM
#34
Former Vendor
Greg, when mark was running speedvision with his 928,it had 420rwhp and he was running 1:40.1 on DOTs. I run 1:36.1 on DOTs. with the track maybe being 1 second faster. now, he has 150hp more and most all of what he is doing now, is power and cornering based due to slicks. He has slicks, which is worth about 2 seconds a lap min vs my garbage can tires. our last times in the dry at laguna, he ran 1:31s and I ran 1:36s. thats 5 seconds. 3 of which are due to power and braking as well as weight. in the end, there is not a hill bit of difference between what mark is doing and what I am doing as far as a transmission wear on the synchros, however, certainly, his extra 150hp has to add even more heat to the gear box, and that could be what you are talking about. BUT, we are not talking about a Joe Fan or Anderson car, we are talking my car or lesser versions. by the way, you and I both know with even 420rwhp, i would have no issues as well!
There would be no song to be sung. a shift is a shift. either you do it right , or you break things and blame the equipment or pay for new stuff because you are just driving "flat out".
Nothing with my car is special, its not an exception, i drive the car as it is meant to be driven, but I am also a student of the sport and have always learned how to go faster and also be easier on the equipment. There is no more force on a synchro with 500wrhp vs my 370rwhp. (5th gear, yes, gears, yes) the difference is in matching the gears. you dont think Im hustling around the track, take a look at my shifts, my blips and shift times.
Unfortunately, many of the "rule" folk, tend to discount the most important rule of racing. use the equipment how it is designed to be used. break that rule, and things break. So, am I the exception, in racing, I could be, but there are others out there that make things last too and go fast. But, there are more of the type that drive fast and break things. Just the way things are.
There would be no song to be sung. a shift is a shift. either you do it right , or you break things and blame the equipment or pay for new stuff because you are just driving "flat out".
Nothing with my car is special, its not an exception, i drive the car as it is meant to be driven, but I am also a student of the sport and have always learned how to go faster and also be easier on the equipment. There is no more force on a synchro with 500wrhp vs my 370rwhp. (5th gear, yes, gears, yes) the difference is in matching the gears. you dont think Im hustling around the track, take a look at my shifts, my blips and shift times.
Unfortunately, many of the "rule" folk, tend to discount the most important rule of racing. use the equipment how it is designed to be used. break that rule, and things break. So, am I the exception, in racing, I could be, but there are others out there that make things last too and go fast. But, there are more of the type that drive fast and break things. Just the way things are.
Some guys can improve and go faster by ability and some guys make up the difference by "beating" on the equipment....and I'm glad that you are the former....it makes the sport so much more ecconomical.
Note that I'm not stating an opinion here...I'm stating a fact...the Borg Warner style syncros are more sensitive to heat/abuse than the older Porsche design syncros. It's all about where the friction surface is and about how you get oil there to cool them. The GT-3 gearboxes that used the Borg Warner style syncros had many modifications to get more oil to the syncros, but it was futile. They killed syncros.
The addition/change to the Tilton clutch was the best thing Porsche ever did for the syncro wear problem, in these cars. But that didn't solve the problem for everyone. I had one of "Porsche's Factory uber Cup Car Wonderchildren" as a driver, at the 24 hours of Daytona, one year. He killed a Borg Warner style gearbox in 45 minutes...Tilton clutch and all. He drove sprint races, in Germany and had learned to not worry about the gearbox. Who cares if they crunched after 45 minutes...they got rebuilt after every event!
You/anyone can use whatever gearbox design they choose. I'm just saying that everyone is always bad mouthing the early gearboxes...and I happen to think they work really well. The design of the syncro allows much faster gear changes than the Borg Warner style syncro, without grinding. As a matter of fact, the less time the hub touches the syncro, the happier the syncro is. That is not the case, with the Borg Warner design.
11-08-2010, 11:08 PM
#35
Race Director
Thread Starter
One can rationalise this stuff forever...I'm not going to try. If you take Mark's best ever lap at Laguna and your best ever lap at Laguna...that's 6-7 seconds. That's an eternity on the race track....like I said.
Some guys can improve and go faster by ability and some guys make up the difference by "beating" on the equipment....and I'm glad that you are the former....it makes the sport so much more ecconomical.
Note that I'm not stating an opinion here...I'm stating a fact...the Borg Warner style syncros are more sensitive to heat/abuse than the older Porsche design syncros. It's all about where the friction surface is and about how you get oil there to cool them. The GT-3 gearboxes that used the Borg Warner style syncros had many modifications to get more oil to the syncros, but it was futile. They killed syncros.
The addition/change to the Tilton clutch was the best thing Porsche ever did for the syncro wear problem, in these cars. But that didn't solve the problem for everyone. I had one of "Porsche's Factory uber Cup Car Wonderchildren" as a driver, at the 24 hours of Daytona, one year. He killed a Borg Warner style gearbox in 45 minutes...Tilton clutch and all. He drove sprint races, in Germany and had learned to not worry about the gearbox. Who cares if they crunched after 45 minutes...they got rebuilt after every event!
You/anyone can use whatever gearbox design they choose. I'm just saying that everyone is always bad mouthing the early gearboxes...and I happen to think they work really well. The design of the syncro allows much faster gear changes than the Borg Warner style syncro, without grinding. As a matter of fact, the less time the hub touches the syncro, the happier the syncro is. That is not the case, with the Borg Warner design.
Some guys can improve and go faster by ability and some guys make up the difference by "beating" on the equipment....and I'm glad that you are the former....it makes the sport so much more ecconomical.
Note that I'm not stating an opinion here...I'm stating a fact...the Borg Warner style syncros are more sensitive to heat/abuse than the older Porsche design syncros. It's all about where the friction surface is and about how you get oil there to cool them. The GT-3 gearboxes that used the Borg Warner style syncros had many modifications to get more oil to the syncros, but it was futile. They killed syncros.
The addition/change to the Tilton clutch was the best thing Porsche ever did for the syncro wear problem, in these cars. But that didn't solve the problem for everyone. I had one of "Porsche's Factory uber Cup Car Wonderchildren" as a driver, at the 24 hours of Daytona, one year. He killed a Borg Warner style gearbox in 45 minutes...Tilton clutch and all. He drove sprint races, in Germany and had learned to not worry about the gearbox. Who cares if they crunched after 45 minutes...they got rebuilt after every event!
You/anyone can use whatever gearbox design they choose. I'm just saying that everyone is always bad mouthing the early gearboxes...and I happen to think they work really well. The design of the syncro allows much faster gear changes than the Borg Warner style syncro, without grinding. As a matter of fact, the less time the hub touches the syncro, the happier the syncro is. That is not the case, with the Borg Warner design.
Then again everyone thinks an automatic will suck on the track & its far from the truth.... sure its not perfect...but given how reliable it is why not run it!!! I do think the Mercedes trans is far stronger than people think! Look at the years of abuse the supercharged crowd has subjected theirs too..... 928 SS was pretty good at abusing his trans too with all the torque of the Doc Brown stroker too!!
11-08-2010, 11:14 PM
#36
Burning Brakes
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Good work, Brian. I think that's the way to go, stick with the auto, add lsd and a refresh and go. Then be ready for the next link in the chain to show it's age.
11-08-2010, 11:16 PM
#37
Race Director
Thread Starter
I think a large part of why the 928 Estate has been so reliable is due to the automatic and its relatively low HP-torque.....its also pretty light...all of these things tend to reduce wear.....not exceeding 6000rpm also helps too...
I am looking forward to the refreshed trans with LSD....should be able to power out of corners better...or at least do some bitchin powerslides!!!
11-09-2010, 12:09 AM
#38
Rennlist Member
Hey, Im with you and its good to know the differences in constructon of the synchros. However, sure, the borg Warner set up might create heat based on design, but if you are shifting properly, you might not develop the heat in the first place.
Now Marks best time with slicks that weekend was 1:31.9, prior, his all time best is 1:30.7, while mine is 1:36.1 call it under 5 seconds difference. I had many 1:36.xxs he had many 1:31s in the race. Again, this has no bearing on shifting, but everything to do with braking/cornering and power.
Sure, beating up the equipment can be fast, but being smarter about it can be more economical and probably faster. without a borg warner synchro and their greater surface area, it uses the actual gear and the grind to complete the shift mesh, but with it, im sure its making up for a lot of mis-shifting, and hiding the effects in the form of heat. however, if shifted correctly, i bet , logically, you would have a lot less heat.
Again, I had the problem that many of the 928 racers complained about. at the end of a 100F degree race at thunderhill, the last few laps were nasty to get the Holbert stock transmission into 2nd gear and even 3-4 gear shifts were notchy. However, as I said, I learned a trick from the cup car drivers. all that blipping and heal toeing sounded really cool and my car had a great high rpm exhauast note, so I started doing for the sound, and also found my shifts were much more crisp and suddenly, I NEVER had a hard-to-shift S4 tranmission shift AGAIN. never, nowhere! 50min speed GT races, club races, whatever.
Now, post your video racers and see if you are shifting correctly. If you want to make your transmission last, you need to heal-toe or match RPM on engine downshifts, to reduce the heat in the transmission and make cleaner, faster, shifts.
The 928 is a hard car to race. no question. go find me the best driver you know, have him take the 928 for a hot lap. it will be ugly as far as shifts. Ive done this. I also drove that drivers regular racer and my shifts looked just like his. it was "Butter" easy! BMWs for example are just a dream to drive and shift. they are very close throw, and are VERY unforgiving for mistakes, but if you are careful, they are amazing to drive. i guarantee, Sofro, pobst, pat long, would BUTCHER a 928 transmission on their first few laps, but im sure after a sesson or two, they could be proficient. any other car, they would be at home at very quickly. In fact, I probably wouldnt let anyone like that drive my car, unless they signed a transmission bond.
Now Marks best time with slicks that weekend was 1:31.9, prior, his all time best is 1:30.7, while mine is 1:36.1 call it under 5 seconds difference. I had many 1:36.xxs he had many 1:31s in the race. Again, this has no bearing on shifting, but everything to do with braking/cornering and power.
Sure, beating up the equipment can be fast, but being smarter about it can be more economical and probably faster. without a borg warner synchro and their greater surface area, it uses the actual gear and the grind to complete the shift mesh, but with it, im sure its making up for a lot of mis-shifting, and hiding the effects in the form of heat. however, if shifted correctly, i bet , logically, you would have a lot less heat.
Again, I had the problem that many of the 928 racers complained about. at the end of a 100F degree race at thunderhill, the last few laps were nasty to get the Holbert stock transmission into 2nd gear and even 3-4 gear shifts were notchy. However, as I said, I learned a trick from the cup car drivers. all that blipping and heal toeing sounded really cool and my car had a great high rpm exhauast note, so I started doing for the sound, and also found my shifts were much more crisp and suddenly, I NEVER had a hard-to-shift S4 tranmission shift AGAIN. never, nowhere! 50min speed GT races, club races, whatever.
Now, post your video racers and see if you are shifting correctly. If you want to make your transmission last, you need to heal-toe or match RPM on engine downshifts, to reduce the heat in the transmission and make cleaner, faster, shifts.
The 928 is a hard car to race. no question. go find me the best driver you know, have him take the 928 for a hot lap. it will be ugly as far as shifts. Ive done this. I also drove that drivers regular racer and my shifts looked just like his. it was "Butter" easy! BMWs for example are just a dream to drive and shift. they are very close throw, and are VERY unforgiving for mistakes, but if you are careful, they are amazing to drive. i guarantee, Sofro, pobst, pat long, would BUTCHER a 928 transmission on their first few laps, but im sure after a sesson or two, they could be proficient. any other car, they would be at home at very quickly. In fact, I probably wouldnt let anyone like that drive my car, unless they signed a transmission bond.
One can rationalise this stuff forever...I'm not going to try. If you take Mark's best ever lap at Laguna and your best ever lap at Laguna...that's 6-7 seconds. That's an eternity on the race track....like I said.
Some guys can improve and go faster by ability and some guys make up the difference by "beating" on the equipment....and I'm glad that you are the former....it makes the sport so much more ecconomical.
Note that I'm not stating an opinion here...I'm stating a fact...the Borg Warner style syncros are more sensitive to heat/abuse than the older Porsche design syncros. It's all about where the friction surface is and about how you get oil there to cool them. The GT-3 gearboxes that used the Borg Warner style syncros had many modifications to get more oil to the syncros, but it was futile. They killed syncros.
The addition/change to the Tilton clutch was the best thing Porsche ever did for the syncro wear problem, in these cars. But that didn't solve the problem for everyone. I had one of "Porsche's Factory uber Cup Car Wonderchildren" as a driver, at the 24 hours of Daytona, one year. He killed a Borg Warner style gearbox in 45 minutes...Tilton clutch and all. He drove sprint races, in Germany and had learned to not worry about the gearbox. Who cares if they crunched after 45 minutes...they got rebuilt after every event!
You/anyone can use whatever gearbox design they choose. I'm just saying that everyone is always bad mouthing the early gearboxes...and I happen to think they work really well. The design of the syncro allows much faster gear changes than the Borg Warner style syncro, without grinding. As a matter of fact, the less time the hub touches the syncro, the happier the syncro is. That is not the case, with the Borg Warner design.
Some guys can improve and go faster by ability and some guys make up the difference by "beating" on the equipment....and I'm glad that you are the former....it makes the sport so much more ecconomical.
Note that I'm not stating an opinion here...I'm stating a fact...the Borg Warner style syncros are more sensitive to heat/abuse than the older Porsche design syncros. It's all about where the friction surface is and about how you get oil there to cool them. The GT-3 gearboxes that used the Borg Warner style syncros had many modifications to get more oil to the syncros, but it was futile. They killed syncros.
The addition/change to the Tilton clutch was the best thing Porsche ever did for the syncro wear problem, in these cars. But that didn't solve the problem for everyone. I had one of "Porsche's Factory uber Cup Car Wonderchildren" as a driver, at the 24 hours of Daytona, one year. He killed a Borg Warner style gearbox in 45 minutes...Tilton clutch and all. He drove sprint races, in Germany and had learned to not worry about the gearbox. Who cares if they crunched after 45 minutes...they got rebuilt after every event!
You/anyone can use whatever gearbox design they choose. I'm just saying that everyone is always bad mouthing the early gearboxes...and I happen to think they work really well. The design of the syncro allows much faster gear changes than the Borg Warner style syncro, without grinding. As a matter of fact, the less time the hub touches the syncro, the happier the syncro is. That is not the case, with the Borg Warner design.
11-09-2010, 12:16 AM
#39
Rennlist Member
Funny! no, 200rwhp doest really buy you those bitch'n power slides out of corners. spend your money on a set of rims and start using up all my 305 RA1s. pull those fenders out and do the MK flares, and you will use 305 on all 4 corners and the car will be 2 -3 seconds faster. the LSD is not a problem with that wide low light 928.
Gee thanks Mike
I think a large part of why the 928 Estate has been so reliable is due to the automatic and its relatively low HP-torque.....its also pretty light...all of these things tend to reduce wear.....not exceeding 6000rpm also helps too...
I am looking forward to the refreshed trans with LSD....should be able to power out of corners better...or at least do some bitchin powerslides!!!
I think a large part of why the 928 Estate has been so reliable is due to the automatic and its relatively low HP-torque.....its also pretty light...all of these things tend to reduce wear.....not exceeding 6000rpm also helps too...
I am looking forward to the refreshed trans with LSD....should be able to power out of corners better...or at least do some bitchin powerslides!!!
11-09-2010, 12:27 AM
#40
Race Director
Thread Starter
Funny! no, 200rwhp doest really buy you those bitch'n power slides out of corners. spend your money on a set of rims and start using up all my 305 RA1s. pull those fenders out and do the MK flares, and you will use 305 on all 4 corners and the car will be 2 -3 seconds faster. the LSD is not a problem with that wide low light 928.
2-3 seconds put me in the 2:06's over the top which is damm fast for only 200whp!!! I still gotta get you in the car on R comps so you can see how much better it handles now! One thing that always sucked on the Widow was the shifting....I liked to call it "rowing an asparagus stalk through marbles" Sean did say fixing the clutch slave cylinder made it much better though.....when the Widow died and I drove spec miata's the single best part was the shifter....short precise throws you could shift with 1 finger!
11-09-2010, 01:42 AM
#41
Former Vendor
One thing that always sucked on the Widow was the shifting....I liked to call it "rowing an asparagus stalk through marbles" Sean did say fixing the clutch slave cylinder made it much better though.....when the Widow died and I drove spec miata's the single best part was the shifter....short precise throws you could shift with 1 finger!
11-09-2010, 01:58 AM
#42
Former Vendor
Then again everyone thinks an automatic will suck on the track & its far from the truth.... sure its not perfect...but given how reliable it is why not run it!!! I do think the Mercedes trans is far stronger than people think! Look at the years of abuse the supercharged crowd has subjected theirs too..... 928 SS was pretty good at abusing his trans too with all the torque of the Doc Brown stroker too!!
They do seem to have a tendency to always have broken springs/pistons in the valve body and it amazes me that they can work, at all, with these kind of defects, but they do.
Amazingly, both Mercedes and Porsche tend to not have a ton of inventory of the pieces needed to "set" one of these things up properly, so I have to keep one of everything in stock, to be able to rebuild them with original parts.
This surprises me, a bit, since there are a zillion of these things out there. I have to assume that most of the rebuilders choose to "optimize" their profits and use "aftermarket" pieces.
I figure that if they made it as many miles as they did, the first time around, I might as well use the same pieces that they came with.
11-09-2010, 02:30 AM
#43
Race Director
Thread Starter
I really like the 4 speed automatics. Very sturdy and very reliable. I've build several automatic stroker cars and they work great....after you "beef" them up a bit and "weed" through all the supercessions of the parts.
They do seem to have a tendency to always have broken springs/pistons in the valve body and it amazes me that they can work, at all, with these kind of defects, but they do.
Amazingly, both Mercedes and Porsche tend to not have a ton of inventory of the pieces needed to "set" one of these things up properly, so I have to keep one of everything in stock, to be able to rebuild them with original parts.
This surprises me, a bit, since there are a zillion of these things out there. I have to assume that most of the rebuilders choose to "optimize" their profits and use "aftermarket" pieces.
I figure that if they made it as many miles as they did, the first time around, I might as well use the same pieces that they came with.
They do seem to have a tendency to always have broken springs/pistons in the valve body and it amazes me that they can work, at all, with these kind of defects, but they do.
Amazingly, both Mercedes and Porsche tend to not have a ton of inventory of the pieces needed to "set" one of these things up properly, so I have to keep one of everything in stock, to be able to rebuild them with original parts.
This surprises me, a bit, since there are a zillion of these things out there. I have to assume that most of the rebuilders choose to "optimize" their profits and use "aftermarket" pieces.
I figure that if they made it as many miles as they did, the first time around, I might as well use the same pieces that they came with.
11-09-2010, 10:58 AM
#44
You sold your M3 Brian?
11-09-2010, 12:27 PM
#45
Rennlist Member
ha ha ha. Im sure you have seen my videos, where i usually aim about 1 foot to the right of where 4th gear should be, just to make sure it goes in there! 
now, with the lever shortened (10years ago) and the broken linkage fixed, (this season with the rebuild and replacement TT and linkage element), its pretty tight, but the gear spacing for 3rd to 4th is like 1st to 5th on a BMW
now, with the lever shortened (10years ago) and the broken linkage fixed, (this season with the rebuild and replacement TT and linkage element), its pretty tight, but the gear spacing for 3rd to 4th is like 1st to 5th on a BMW
