968 Supercharger Kit Development
06-09-2009, 11:25 PM
#256
Rennlist Member
Carl,
Awesome job! I am grateful that you where willing to develop a product for the 968 considering it's age and market value. This has got to be one of the fastest concept to product ideas I have seen. When I was looking at going the turbo route, I was looking at $20,000 to $25,000 to get it done. So, to have a plug and play kit for around $5,000 is truly remarkable. Again, great job and many thanks from this 968 owner.
Awesome job! I am grateful that you where willing to develop a product for the 968 considering it's age and market value. This has got to be one of the fastest concept to product ideas I have seen. When I was looking at going the turbo route, I was looking at $20,000 to $25,000 to get it done. So, to have a plug and play kit for around $5,000 is truly remarkable. Again, great job and many thanks from this 968 owner.
06-09-2009, 11:36 PM
#257
Developer
Thread Starter
Thanks to all for your kind words.
The last of the parts were farmed out to machine shops and manufacturing houses today, and I also received bids back on the first parts I let out last week. They will be in production soon.
When the production parts come back, the last step will be for me to install them one-by-one with camera and write the installation manual.
As to the Next Stage: I'd like to see some Stage 1 sales before I invest in more development for this car. Stage 2 is most certainly going to require a crankshaft pulley replacement (larger) because we cannot go much smaller on the supercharger inoput shaft pulley without getting into some belt slippage problems and I dont want that. So instead of making the blower pulley smaller, you make the crank pulley larger (same effect, but less belt slippage).
As to the S2: my research suggests that it should fit 1988-1992 S2 models. I know the S2 started in 1985, but it was not until 1988 that they adopted the "short" radiator that we need to get the room for the supercharger.
I'd like someone to bring be an S2 this fall (after I get back from racing Pikes Peak) and we would test-fit the kit to it to be sure.
The last of the parts were farmed out to machine shops and manufacturing houses today, and I also received bids back on the first parts I let out last week. They will be in production soon.
When the production parts come back, the last step will be for me to install them one-by-one with camera and write the installation manual.
As to the Next Stage: I'd like to see some Stage 1 sales before I invest in more development for this car. Stage 2 is most certainly going to require a crankshaft pulley replacement (larger) because we cannot go much smaller on the supercharger inoput shaft pulley without getting into some belt slippage problems and I dont want that. So instead of making the blower pulley smaller, you make the crank pulley larger (same effect, but less belt slippage).
As to the S2: my research suggests that it should fit 1988-1992 S2 models. I know the S2 started in 1985, but it was not until 1988 that they adopted the "short" radiator that we need to get the room for the supercharger.
I'd like someone to bring be an S2 this fall (after I get back from racing Pikes Peak) and we would test-fit the kit to it to be sure.
06-09-2009, 11:46 PM
#258
Instructor
Join Date: Dec 2008
Location: bahrain
Posts: 183
Likes: 0
Received 0 Likes
on
0 Posts
968 supercharger kit
someone raised on this forum questions about the 968 injector ratings ,with a value of 19 lbs mentioned, which is actually the rating for a n/a 944.
and are only good to about 140 BHP AT 3 BAR.,not for the 968.
The 968 bosch high impedance injectors p/n 1-280-155-010 are rated
at 32.5 lbs at 3.0 bar and are good for 50 BHP /INJECTOR at 80 % duty cycle.
when adjusted to the 3.8 BAR as used in 968 the fuel flow increases by about
8 %. hence the 3 litre engine gives236- 240 bhp.
when the duty cycle increases to 95-100% , by software changes this figure
can very well jump to , 285 BHP MAX.
It is clear that what ever the power increase above that , a different injector will be required, or a fuel pressure needs to be adjusted higher,and perhaps a new high flow pump will be in order.
and are only good to about 140 BHP AT 3 BAR.,not for the 968.
The 968 bosch high impedance injectors p/n 1-280-155-010 are rated
at 32.5 lbs at 3.0 bar and are good for 50 BHP /INJECTOR at 80 % duty cycle.
when adjusted to the 3.8 BAR as used in 968 the fuel flow increases by about
8 %. hence the 3 litre engine gives236- 240 bhp.
when the duty cycle increases to 95-100% , by software changes this figure
can very well jump to , 285 BHP MAX.
It is clear that what ever the power increase above that , a different injector will be required, or a fuel pressure needs to be adjusted higher,and perhaps a new high flow pump will be in order.
06-10-2009, 12:56 AM
#259
This is incredible, I have rarely seen anyone accomplish something like this so fast in any hobby/interest.. Great job Carl! You said you were gonna do it, and before I could go thru this thread it was done! Was your test car dynoed prior to the supercharger fitment? I doubt it made 236HP at the flywheel (that's a 60hp increase with the supercharger) it's probably more like 70-80HP increase over your stock setup.. you mentioned a 100k+ car. In that case no one should be complaining about the $4k cost. A Stage 2 setup with an intercooler/larger fuel injectors or larger crankshaft pulley would be a sweet upgrade, putting an intercooler in there would be more work than the bolt-on supercharger itself; which goes against your initial testament of easy DIY kinda deal..
If I had the money.. I love that whirlllll!
Whatever happened to the speedforce racing supercharger? http://www.speedforceracing.com/index.php?productID=736
If I had the money.. I love that whirlllll!
Whatever happened to the speedforce racing supercharger? http://www.speedforceracing.com/index.php?productID=736
06-10-2009, 02:21 AM
#260
Official Rennlist
Borat Impersonator
Rennlist Member
Borat Impersonator
Rennlist Member
Thanks to all for your kind words.
The last of the parts were farmed out to machine shops and manufacturing houses today, and I also received bids back on the first parts I let out last week. They will be in production soon.
When the production parts come back, the last step will be for me to install them one-by-one with camera and write the installation manual.
As to the Next Stage: I'd like to see some Stage 1 sales before I invest in more development for this car. Stage 2 is most certainly going to require a crankshaft pulley replacement (larger) because we cannot go much smaller on the supercharger inoput shaft pulley without getting into some belt slippage problems and I dont want that. So instead of making the blower pulley smaller, you make the crank pulley larger (same effect, but less belt slippage).
As to the S2: my research suggests that it should fit 1988-1992 S2 models. I know the S2 started in 1985, but it was not until 1988 that they adopted the "short" radiator that we need to get the room for the supercharger.
I'd like someone to bring be an S2 this fall (after I get back from racing Pikes Peak) and we would test-fit the kit to it to be sure.
The last of the parts were farmed out to machine shops and manufacturing houses today, and I also received bids back on the first parts I let out last week. They will be in production soon.
When the production parts come back, the last step will be for me to install them one-by-one with camera and write the installation manual.
As to the Next Stage: I'd like to see some Stage 1 sales before I invest in more development for this car. Stage 2 is most certainly going to require a crankshaft pulley replacement (larger) because we cannot go much smaller on the supercharger inoput shaft pulley without getting into some belt slippage problems and I dont want that. So instead of making the blower pulley smaller, you make the crank pulley larger (same effect, but less belt slippage).
As to the S2: my research suggests that it should fit 1988-1992 S2 models. I know the S2 started in 1985, but it was not until 1988 that they adopted the "short" radiator that we need to get the room for the supercharger.
I'd like someone to bring be an S2 this fall (after I get back from racing Pikes Peak) and we would test-fit the kit to it to be sure.
I hereby volunteer my 91 S2 for test fitting!
06-10-2009, 05:42 AM
#261
Rennlist Member
Join Date: Jul 2001
Location: Brisbane, Australia (Formerly: Sunnyvale, CA)
Posts: 2,120
Likes: 0
Received 3 Likes
on
3 Posts
Stage 2 is most certainly going to require a crankshaft pulley replacement (larger) because we cannot go much smaller on the supercharger inoput shaft pulley without getting into some belt slippage problems and I dont want that. So instead of making the blower pulley smaller, you make the crank pulley larger (same effect, but less belt slippage).
Would this be a problem for (economical) fabrication of larger pulleys?
Edit: Upon reading up a bit, the S2 crank pulley is a harmonic balancer, but the 968 pulley may not be -- the 968 has a dual mass flywheel instead, which differs from the S2. If anyone knows for sure please chime in.
Last edited by Mark944na86; 06-10-2009 at 07:17 AM.
06-10-2009, 10:23 AM
#262
Developer
Thread Starter
Savvass944 - thanks for the fuel injector info. Good stuff.
If we "need" a crank pulley with harmonic balancer, I can get that made.
We make them with ATI now - here is a link:
http://www.928motorsports.com/parts/harmonic_damper.php
But lets not go there yet. Usually (knowing Porsche) the plastic timing belt covers are pretty form fitted and a larger crank puleey and damper will require they be removed or altered - something I'd like to avoid.
About the S2.... I am serious. If there is one within the tri-state area (Iliinois, Wisconsin, Minnesota, maybe Iowa) that can get here this fall, I'd like to test fit the kit to it and take pictures and measurements.
If we "need" a crank pulley with harmonic balancer, I can get that made.
We make them with ATI now - here is a link:
http://www.928motorsports.com/parts/harmonic_damper.php
But lets not go there yet. Usually (knowing Porsche) the plastic timing belt covers are pretty form fitted and a larger crank puleey and damper will require they be removed or altered - something I'd like to avoid.
About the S2.... I am serious. If there is one within the tri-state area (Iliinois, Wisconsin, Minnesota, maybe Iowa) that can get here this fall, I'd like to test fit the kit to it and take pictures and measurements.
06-10-2009, 02:39 PM
#265
Rennlist Member
Raj
06-11-2009, 01:25 AM
#266
Instructor
Join Date: Dec 2008
Location: bahrain
Posts: 183
Likes: 0
Received 0 Likes
on
0 Posts
speedforce racing supercharger kit fo 6,166 usd?315 hp at wheels/385at flywheel?
looks very professional,with software , big injectors and that intercooler and plumbing mean business.
something that should have been included though is an uprated clutch as that std will not last very long
and what a pity , the A.C. needs to go.
by the way,for whoever is interested, i have thrown the dual mass 13.2 kg flywheel in the bin and intalled a spec aluminium one at 6 kg . No vibrations at all, the engine revs so freely and the in gear acceleration is fantastic as if there were another 20 bhp on the engine. Also the gearchanges improved.
giving a lot less strain on the synchros with increased reliability.
best value for money at 625 usd.
Minor drawback , with std chips needed a bit more throttle to launch from traffic, with the promax chip
i have now this is gone.
a german chief automobile engineer once told me that the dual mass was made for the very light cranks of 993 and onwards, but the 968 crank is so heavy and correctly balanced ,does not need one.
Nevertheless the decision was taken by the factory to proceed anyway as they had a good deal with
the subcontractor who developed the dual mass flywheel for them, for the sake of change.
the 968 turbo used single mass flywheel.
looks very professional,with software , big injectors and that intercooler and plumbing mean business.
something that should have been included though is an uprated clutch as that std will not last very long
and what a pity , the A.C. needs to go.
by the way,for whoever is interested, i have thrown the dual mass 13.2 kg flywheel in the bin and intalled a spec aluminium one at 6 kg . No vibrations at all, the engine revs so freely and the in gear acceleration is fantastic as if there were another 20 bhp on the engine. Also the gearchanges improved.
giving a lot less strain on the synchros with increased reliability.
best value for money at 625 usd.
Minor drawback , with std chips needed a bit more throttle to launch from traffic, with the promax chip
i have now this is gone.
a german chief automobile engineer once told me that the dual mass was made for the very light cranks of 993 and onwards, but the 968 crank is so heavy and correctly balanced ,does not need one.
Nevertheless the decision was taken by the factory to proceed anyway as they had a good deal with
the subcontractor who developed the dual mass flywheel for them, for the sake of change.
the 968 turbo used single mass flywheel.
06-11-2009, 01:37 AM
#267
Rennlist Member
06-11-2009, 01:46 AM
#268
RL Community Team
Rennlist Member
Rennlist Member
Carl, if a larger crank pulley is made, will we also need a larger alternator pulley to compensate? No big deal though.
Savvas, I'm glad you like your lightweight flywheel. I'm using an S2 flywheel, with harmonic balancer, and it is not as smooth as the DMF, gear changing has definitely become more notchy, and it does rattle a little bit. I guess it's just a big case of YMMV.
Savvas, I'm glad you like your lightweight flywheel. I'm using an S2 flywheel, with harmonic balancer, and it is not as smooth as the DMF, gear changing has definitely become more notchy, and it does rattle a little bit. I guess it's just a big case of YMMV.
06-11-2009, 08:07 AM
#269
Instructor
Join Date: Dec 2008
Location: bahrain
Posts: 183
Likes: 0
Received 0 Likes
on
0 Posts
Hi Fr porscheman,
Did you change the dme CHIP,perhaps thats were the notchines comes from .Try the promax 7700 RT,you will be surprised at the difference for about 135 USD.NO AFFILIATION at all.any thing else is useless.
Dont know about the S2 flywheel set up, but i think is much more heavy than the Aluminium set up as well. Also i am using Liquid Moly 75/140 Lsd oil, perhaps the whole thing works in synergy and i get. these results.
Also in the engine i use 10-60 FULL SYNTHETIC oil., and the oil thermostat is the 95 degree one instead of the 105 Degree that the factory use.
Did you change the dme CHIP,perhaps thats were the notchines comes from .Try the promax 7700 RT,you will be surprised at the difference for about 135 USD.NO AFFILIATION at all.any thing else is useless.
Dont know about the S2 flywheel set up, but i think is much more heavy than the Aluminium set up as well. Also i am using Liquid Moly 75/140 Lsd oil, perhaps the whole thing works in synergy and i get. these results.
Also in the engine i use 10-60 FULL SYNTHETIC oil., and the oil thermostat is the 95 degree one instead of the 105 Degree that the factory use.
06-11-2009, 11:28 PM
#270
Rennlist Member
Join Date: May 2001
Location: North Of Chicago
Posts: 1,992
Likes: 0
Received 0 Likes
on
0 Posts
If Borys can't help you out since he volunteered first, I certainly can. I am even close to the WI border.
Cheers!