968 Supercharger
11-09-2015, 03:00 AM
#16
Three Wheelin'
Speedforceracing.com
They have a few different supercharger setups, and the tuning and add ons to go with.
These guys have some good quality stuff and most of it comes with a bit of R & D
Lead times on some of the very special stuff may be a week or 2 but communication is there an there realists.
They have a few different supercharger setups, and the tuning and add ons to go with.
These guys have some good quality stuff and most of it comes with a bit of R & D
Lead times on some of the very special stuff may be a week or 2 but communication is there an there realists.
11-09-2015, 05:54 AM
#17
I have a Design 1 Racing supercharger. I started with the Stage 1, then moved directly to Stage 3. So far, it's been great.
I was initially very concerned about adding complexity to an engine I consider to be (overly) complex already, based on serious issues I had years ago with the 944S. That car cost me a lot of money in maintenance and failures, and finding someone qualified to work on it was just as hard then as it is with the 968 today. It took me quite a few years to want to get back into p-cars because of that one bad car.
Thankfully, I haven't had any of the issues with the 968 that I had with that car, but you understand my hesitation. Overall, I just think the timing belts are a horrible design for this size engine and fail way too often (although I've never had one myself, they're altogether too common from what I read of other peoples' experience), and the entire top end feels like a high-dollar maintenance item "waiting to happen".
Perhaps I've been very fortunate, and just haven't run into any issues yet? I just figured I'd share my experience, which so far has been very positive. Of course having said that, I'll go out to the garage this morning and find a puddle of supercharger blood on the floor or something...
I was initially very concerned about adding complexity to an engine I consider to be (overly) complex already, based on serious issues I had years ago with the 944S. That car cost me a lot of money in maintenance and failures, and finding someone qualified to work on it was just as hard then as it is with the 968 today. It took me quite a few years to want to get back into p-cars because of that one bad car.
Thankfully, I haven't had any of the issues with the 968 that I had with that car, but you understand my hesitation. Overall, I just think the timing belts are a horrible design for this size engine and fail way too often (although I've never had one myself, they're altogether too common from what I read of other peoples' experience), and the entire top end feels like a high-dollar maintenance item "waiting to happen".
Perhaps I've been very fortunate, and just haven't run into any issues yet? I just figured I'd share my experience, which so far has been very positive. Of course having said that, I'll go out to the garage this morning and find a puddle of supercharger blood on the floor or something...
11-09-2015, 09:42 AM
#18
Rennlist Member
Good to hear that some have had positive experience with the unit you currently run.
As far as maintenance, for a 968, its not the timing belt but the BS belt that is the bigger concern. The timing belt is quite stout and with the hydraulic tensioner, you are in good shape. The balance shaft belt is the weakest link in my opinion and its failure can cause the timing belt to fail.
As far as the top end issues, the tensioner mounting has been fixed from a 2 bolt (944s/s2) to a 3 bolt design. Also, variocam is a great technology that uses the tensioner to adjust timing. These are typically 60K items and depending on usage should not be required as often.
Regards,
Raj
As far as maintenance, for a 968, its not the timing belt but the BS belt that is the bigger concern. The timing belt is quite stout and with the hydraulic tensioner, you are in good shape. The balance shaft belt is the weakest link in my opinion and its failure can cause the timing belt to fail.
As far as the top end issues, the tensioner mounting has been fixed from a 2 bolt (944s/s2) to a 3 bolt design. Also, variocam is a great technology that uses the tensioner to adjust timing. These are typically 60K items and depending on usage should not be required as often.
Regards,
Raj
11-09-2015, 01:24 PM
#19
Racer
Join Date: Oct 2003
Location: Palm Beach, FL / Hamburg, DE
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My experience with the Stage 3 D1R supercharger was more mixed. Unfortunately, everything what could fail did fail: Exhaust fell off, AC holding bolt broke, idler pulley and one of the metal pulleys of the SC failed, MAF failed, idler valve failed or was found to have failed. While trouble-shooting the alarm module failed with non-start and other electrical gremlins seem to have gotten woken up.The power of the SC was such that I felt no longer safe driving with the 86’ NA transmission and a re-built AOR transmission had to be sourced from Germany. While installing the transmission it was noted that parts of the clutch was worn out and where also replaced. Lifting up the car (incorrectly?) caused the lifting points and rocker to fail, now I have rust issues (if not present before) and the car needs bodywork.
If we are all in the car (two adults, two children) in a hot Summer day (South Florida, AC) keeping the car in a lower gear for slicing through light rush hour traffic, the temperature gauge does go into the red zone, which shouldn’t be a big surprise since the 86’ NA radiator and fans were not designed for a supercharged 968 motor. Motor still shutters under acceleration when cold (idler valve seized up again?).
On the positive side, the car really wakes up with the SC. Also Bob Larson has been very responsive and helpful.
I feel the biggest difference might not be so much the additional ponies but the different performance characteristics due to the centrifugal charger, there is noticeably more power when getting into higher RPMs, which makes the car more fun to drive.
P.S. Bob Larson never asked or mentioned a gag order to me.
If we are all in the car (two adults, two children) in a hot Summer day (South Florida, AC) keeping the car in a lower gear for slicing through light rush hour traffic, the temperature gauge does go into the red zone, which shouldn’t be a big surprise since the 86’ NA radiator and fans were not designed for a supercharged 968 motor. Motor still shutters under acceleration when cold (idler valve seized up again?).
On the positive side, the car really wakes up with the SC. Also Bob Larson has been very responsive and helpful.
I feel the biggest difference might not be so much the additional ponies but the different performance characteristics due to the centrifugal charger, there is noticeably more power when getting into higher RPMs, which makes the car more fun to drive.
P.S. Bob Larson never asked or mentioned a gag order to me.
Last edited by MN; 11-09-2015 at 01:39 PM.
11-09-2015, 01:25 PM
#20
Happily Amused
Rennlist Member
Rennlist Member
11-09-2015, 01:59 PM
#21
Sorry to hear about your problems, and I hope you get everything sorted. Are you running the supercharger on a 968 motor, but transplanted into a 1986 944?
11-09-2015, 02:41 PM
#22
Racer
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Are you running the supercharger on a 968 motor, but transplanted into a 1986 944?
hope you get everything sorted
11-10-2015, 12:14 AM
#24
Team Owner
Join Date: Oct 2009
Location: one thousand, five hundred miles north of Ft. Lauderdale for the summer.
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wow. fantastic posts resurrecting an enthusiast forum!!
great post!
best wishes with your thumpin' sleepers!! 
great post!
I have a Design 1 Racing supercharger. I started with the Stage 1, then moved directly to Stage 3. So far, it's been great.
I was initially very concerned about adding complexity to an engine I consider to be (overly) complex already, based on serious issues I had years ago with the 944S. That car cost me a lot of money in maintenance and failures, and finding someone qualified to work on it was just as hard then as it is with the 968 today. It took me quite a few years to want to get back into p-cars because of that one bad car.
Thankfully, I haven't had any of the issues with the 968 that I had with that car, but you understand my hesitation. Overall, I just think the timing belts are a horrible design for this size engine and fail way too often (although I've never had one myself, they're altogether too common from what I read of other peoples' experience), and the entire top end feels like a high-dollar maintenance item "waiting to happen".
Perhaps I've been very fortunate, and just haven't run into any issues yet? I just figured I'd share my experience, which so far has been very positive. Of course having said that, I'll go out to the garage this morning and find a puddle of supercharger blood on the floor or something...
I was initially very concerned about adding complexity to an engine I consider to be (overly) complex already, based on serious issues I had years ago with the 944S. That car cost me a lot of money in maintenance and failures, and finding someone qualified to work on it was just as hard then as it is with the 968 today. It took me quite a few years to want to get back into p-cars because of that one bad car.
Thankfully, I haven't had any of the issues with the 968 that I had with that car, but you understand my hesitation. Overall, I just think the timing belts are a horrible design for this size engine and fail way too often (although I've never had one myself, they're altogether too common from what I read of other peoples' experience), and the entire top end feels like a high-dollar maintenance item "waiting to happen".
Perhaps I've been very fortunate, and just haven't run into any issues yet? I just figured I'd share my experience, which so far has been very positive. Of course having said that, I'll go out to the garage this morning and find a puddle of supercharger blood on the floor or something...
My experience with the Stage 3 D1R supercharger was more mixed. Unfortunately, everything what could fail did fail: Exhaust fell off, AC holding bolt broke, idler pulley and one of the metal pulleys of the SC failed, MAF failed, idler valve failed or was found to have failed. While trouble-shooting the alarm module failed with non-start and other electrical gremlins seem to have gotten woken up.The power of the SC was such that I felt no longer safe driving with the 86’ NA transmission and a re-built AOR transmission had to be sourced from Germany. While installing the transmission it was noted that parts of the clutch was worn out and where also replaced. Lifting up the car (incorrectly?) caused the lifting points and rocker to fail, now I have rust issues (if not present before) and the car needs bodywork.
If we are all in the car (two adults, two children) in a hot Summer day (South Florida, AC) keeping the car in a lower gear for slicing through light rush hour traffic, the temperature gauge does go into the red zone, which shouldn’t be a big surprise since the 86’ NA radiator and fans were not designed for a supercharged 968 motor. Motor still shutters under acceleration when cold (idler valve seized up again?).
On the positive side, the car really wakes up with the SC. Also Bob Larson has been very responsive and helpful.
I feel the biggest difference might not be so much the additional ponies but the different performance characteristics due to the centrifugal charger, there is noticeably more power when getting into higher RPMs, which makes the car more fun to drive....
If we are all in the car (two adults, two children) in a hot Summer day (South Florida, AC) keeping the car in a lower gear for slicing through light rush hour traffic, the temperature gauge does go into the red zone, which shouldn’t be a big surprise since the 86’ NA radiator and fans were not designed for a supercharged 968 motor. Motor still shutters under acceleration when cold (idler valve seized up again?).
On the positive side, the car really wakes up with the SC. Also Bob Larson has been very responsive and helpful.
I feel the biggest difference might not be so much the additional ponies but the different performance characteristics due to the centrifugal charger, there is noticeably more power when getting into higher RPMs, which makes the car more fun to drive....
11-13-2015, 06:08 PM
#25
Advanced
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I have over 2 1/2 years and 8,000 miles on my Stage 3 Design 1R supercharger in my '94 968. My experience is pretty much the same as tamathumper. I have had to change both idler pulleys (standard Dayco part as mentioned), but otherwise zero problems. It's really a pretty well designed system. The tuning is set for street driving, not racing, so the torque comes on very smoothly from about 3,500 to 6,000 rpm. Max boost is only 5psig. It does transform the car in a very positive way. I neither signed not heard of a gag order.
11-13-2015, 09:17 PM
#26
Rainman
Rennlist Member
Rennlist Member
Don't know how many people out there can say this, but I've met Bob (Design1) and been to his house before.
Seen the kits in the box and as installed on his own car and it looks super clean, very nice attention to detail. It looks like it could be an OEM thing, it's that well put together.
Having talked to him about that kit and some other things he offers as products and general 968 ownership experience, I don't get the impression that he needs to hide anything - he knows what he wants out of something and will do what it takes to get there and be done right, cost be damned.
I have heard of some bad blood between him and some other 968 gurus in years past and won't comment on that at all since it was before my time here...but I wanted to share.
Seen the kits in the box and as installed on his own car and it looks super clean, very nice attention to detail. It looks like it could be an OEM thing, it's that well put together.
Having talked to him about that kit and some other things he offers as products and general 968 ownership experience, I don't get the impression that he needs to hide anything - he knows what he wants out of something and will do what it takes to get there and be done right, cost be damned.
I have heard of some bad blood between him and some other 968 gurus in years past and won't comment on that at all since it was before my time here...but I wanted to share.
11-14-2015, 04:05 PM
#27
Drifting
I picked up a new unused set of Carrillo rods from a supercharged 968 owner, the engine went pop a 2nd time before he had a chance to fit them, and he gave up on it.
11-18-2015, 11:55 PM
#28
Track Day
Join Date: Sep 2013
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I have a Stage 3 D1R supercharger in my car and love it. My head gasket did give out but it was a very small "hole", so I actually drove it home, then to the mechanic without a problem. I knew I was taking this risk and I accepted the consequences. Bob warned me that it was probable because of the miles on my engine, 112,000. Now I have a valve job and new head gasket, so I don't mind. The extra power is intoxicating. I have had no other problems with the supercharger in the year that it has been in my car.
Also, no gag order, of course. That statement is ridiculous.
Also, no gag order, of course. That statement is ridiculous.
11-20-2015, 09:15 AM
#29
Racer
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My head gasket did give out
The extra power is intoxicating
11-23-2015, 08:48 PM
#30
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Just back in the mix… glad to see everyone still so passionate. Good to see some of the long experienced guys still around.
I've played with the Ls option but never leaped. Superchargers seemed to come and go. Turbo IMHO of the 8V motor of my 951 was a blast…
Cheers, Mike
PS I still type terrible
I've played with the Ls option but never leaped. Superchargers seemed to come and go. Turbo IMHO of the 8V motor of my 951 was a blast…
Cheers, Mike
PS I still type terrible