9m 968 supercharger conversion - 360, 430 or 480hp....
05-14-2007, 07:39 PM
#1
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9m 968 supercharger conversion - 360, 430 or 480hp....
Not content to rest on our laurels with the standard 360hp 9m supercharger conversion, after a customers new supercharger unit arrived at our workshop with the wrong pulley fitted, to get the job out of the door (and with the custmer's blessing) we fitted the correct blower from our own car to ensure that the engine ran as the expected 7psi boost. Once the customers job was finished we were left with our debilitated 968, so it would have been simply rude not to fit the new blower with its smaller pulley and see what happens when you run a stock engine at 11psi of boost.
A few weeks later we had fitted larger injectors and further remapped the ecu, but the first pulls on the dyno managed to melt the cat and highlighted a durability problem with the stock 6 rib belt drive. Decatting the exhaust was a no-brainer, remaking the crank, alternator and supercharger pulleys to run an 8 rib belt took a few weeks longer, but the result was a further 50hp over the basic 9m supercharger conversion. After 18 months track testing this package we were comfortable to offer this kit as a secondary upgrade provided that the customer accepts total responsibility for the engine.
The latest stage of our development came about when we had the opportunity to rework a customer's previously supercharged 968CS with the supercharger from the 9m kit. The original conversion used a pro-charger unit, our customer eventually adding Motec engine management and reducing the compression ratio of his engine in an attempt to get the engine running satiusfactorily. In the end an unexpected supercharger failure combined with our experience of Motec brought him to 9m to have our supercharger fitted and the new package remapped. The car already benefitted from a set of headers and a cat free exhaust, so tje only extras required were a set of 750cc injectors, a high capacity fuel pump and the 9m 8 rib pulley set. Running the superharger with the smallest pulley available resulted in 1.1bar boost at 6500rpm, and once the Motec had been dialed in the result was an astonishing 480hp and 400lbft, the power exactly double that of a standard car.
Makes you wonder why you would bother with the hassle of fitting a turbocharger.....
A few weeks later we had fitted larger injectors and further remapped the ecu, but the first pulls on the dyno managed to melt the cat and highlighted a durability problem with the stock 6 rib belt drive. Decatting the exhaust was a no-brainer, remaking the crank, alternator and supercharger pulleys to run an 8 rib belt took a few weeks longer, but the result was a further 50hp over the basic 9m supercharger conversion. After 18 months track testing this package we were comfortable to offer this kit as a secondary upgrade provided that the customer accepts total responsibility for the engine.
The latest stage of our development came about when we had the opportunity to rework a customer's previously supercharged 968CS with the supercharger from the 9m kit. The original conversion used a pro-charger unit, our customer eventually adding Motec engine management and reducing the compression ratio of his engine in an attempt to get the engine running satiusfactorily. In the end an unexpected supercharger failure combined with our experience of Motec brought him to 9m to have our supercharger fitted and the new package remapped. The car already benefitted from a set of headers and a cat free exhaust, so tje only extras required were a set of 750cc injectors, a high capacity fuel pump and the 9m 8 rib pulley set. Running the superharger with the smallest pulley available resulted in 1.1bar boost at 6500rpm, and once the Motec had been dialed in the result was an astonishing 480hp and 400lbft, the power exactly double that of a standard car.
Makes you wonder why you would bother with the hassle of fitting a turbocharger.....
05-15-2007, 09:23 AM
#4
Nordschleife Master
Colin,
Supercharging my Frankencar has always been in the back of my mind. My concerns are reliability at the track and how well it will perform in the high heat and humidity of the southern US. I'm specifically interested in hearing about the 360 HP conversion.
Supercharging my Frankencar has always been in the back of my mind. My concerns are reliability at the track and how well it will perform in the high heat and humidity of the southern US. I'm specifically interested in hearing about the 360 HP conversion.
05-15-2007, 09:27 AM
#5
Burning Brakes
Looks nice Colin.
Once you reduce the compression ratio, use different headers, injectors and fit Motec its not that different to a turbo conversion though. With the turbo you get better midrange power, albeit in a trade off for some lag which you don't have with a supercharger of course. Nice to see you are still developing the 968, just a shame more people are not taking up these fantastic power upgrades for such a great car. If I had to start all over again I may well have chose the SC route, but I never seem to take the easy road!
I am still to refine my Motec M400 that I have fitted to my 968 turbo. If I can't get it how I want it I may give you a call as I havent had much luck with the dyno I used first time round. Before I go back to another dyno I will need to make up a custom intercooler as the 951 IC in the front lower location is not cutting it as well as blocking off the air flow to the rad leading to less than ideal cooling. Apart from that, just chasing down a couple of leaks in the exhaust system and its more or less where I want it.
Once you reduce the compression ratio, use different headers, injectors and fit Motec its not that different to a turbo conversion though. With the turbo you get better midrange power, albeit in a trade off for some lag which you don't have with a supercharger of course. Nice to see you are still developing the 968, just a shame more people are not taking up these fantastic power upgrades for such a great car. If I had to start all over again I may well have chose the SC route, but I never seem to take the easy road!
I am still to refine my Motec M400 that I have fitted to my 968 turbo. If I can't get it how I want it I may give you a call as I havent had much luck with the dyno I used first time round. Before I go back to another dyno I will need to make up a custom intercooler as the 951 IC in the front lower location is not cutting it as well as blocking off the air flow to the rad leading to less than ideal cooling. Apart from that, just chasing down a couple of leaks in the exhaust system and its more or less where I want it.
05-15-2007, 11:29 AM
#6
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Originally Posted by nick_968
Looks nice Colin.
Once you reduce the compression ratio, use different headers, injectors and fit Motec its not that different to a turbo conversion though. With the turbo you get better midrange power.
Once you reduce the compression ratio, use different headers, injectors and fit Motec its not that different to a turbo conversion though. With the turbo you get better midrange power.
Also, there is no limitations to turbo charging as far as boost level goes. As long as you have your fuel maps covered, you won't be limited by pulley size to the max boost you can run.
Raj
05-15-2007, 11:38 AM
#7
Racer
Originally Posted by Lemming
Colin,
... My concerns are reliability at the track and how well it will perform in the high heat and humidity of the southern US. ...
... My concerns are reliability at the track and how well it will perform in the high heat and humidity of the southern US. ...
Grant
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05-15-2007, 12:39 PM
#9
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There are now eight 9m supercharged 968's on the road and one other track car that started the ball rolling with the very first SFR kit, we budgeted the development at 10 kits to break-even point so as far as 9m is concerned (assuming that we will sell 2 more kits!) the project is a success.
I take yours (and Raj's) point with respect to the turbo conversion being not far off the 9m low comp package, but keep in mind that you do not need to fit an unobtainble 2.7 cylinder head and old 944 turbo manifold parts on our conversion, so even though the engine work and management changes are similar (Motec was the customer's choice, we could have retained Motronic) the cost is lower with the SC engine. As for useable torque, my view (based on a good few years of racing) is that I would rather drive the progressive SC torque curve in real road conditions than have to deal with the typical mid range torque spike of a typical high hp turbo engine. It is a fact that the 968 chassis suffers in comparison to the rear engined 911 with its ability to put the torque down to the road, but in any case I am sure that 400lbft would be enough to keep most folk entertained!
If you are having trouble with Motec mapping you should bring it up here as I have yet to work on a car mapped elsewhere that did not benefit from a bit of 9m fine tuning - in fact the 480hp car as arrived made just 400hp on the exisiting map. With respect to the intercooler, you could always consider the 9m SC intercooler/rad assembly which drops straight in from above the engine bay on the standard mountings, no intake temp problems have been encountered to date at up to 480hp and on some pretty hot track days. The price of the combined unit would be £1500 +VAT.
I take yours (and Raj's) point with respect to the turbo conversion being not far off the 9m low comp package, but keep in mind that you do not need to fit an unobtainble 2.7 cylinder head and old 944 turbo manifold parts on our conversion, so even though the engine work and management changes are similar (Motec was the customer's choice, we could have retained Motronic) the cost is lower with the SC engine. As for useable torque, my view (based on a good few years of racing) is that I would rather drive the progressive SC torque curve in real road conditions than have to deal with the typical mid range torque spike of a typical high hp turbo engine. It is a fact that the 968 chassis suffers in comparison to the rear engined 911 with its ability to put the torque down to the road, but in any case I am sure that 400lbft would be enough to keep most folk entertained!
If you are having trouble with Motec mapping you should bring it up here as I have yet to work on a car mapped elsewhere that did not benefit from a bit of 9m fine tuning - in fact the 480hp car as arrived made just 400hp on the exisiting map. With respect to the intercooler, you could always consider the 9m SC intercooler/rad assembly which drops straight in from above the engine bay on the standard mountings, no intake temp problems have been encountered to date at up to 480hp and on some pretty hot track days. The price of the combined unit would be £1500 +VAT.
Originally Posted by nick_968
Looks nice Colin.
Once you reduce the compression ratio, use different headers, injectors and fit Motec its not that different to a turbo conversion though. With the turbo you get better midrange power, albeit in a trade off for some lag which you don't have with a supercharger of course. Nice to see you are still developing the 968, just a shame more people are not taking up these fantastic power upgrades for such a great car. If I had to start all over again I may well have chose the SC route, but I never seem to take the easy road!
I am still to refine my Motec M400 that I have fitted to my 968 turbo. If I can't get it how I want it I may give you a call as I havent had much luck with the dyno I used first time round. Before I go back to another dyno I will need to make up a custom intercooler as the 951 IC in the front lower location is not cutting it as well as blocking off the air flow to the rad leading to less than ideal cooling. Apart from that, just chasing down a couple of leaks in the exhaust system and its more or less where I want it.
Once you reduce the compression ratio, use different headers, injectors and fit Motec its not that different to a turbo conversion though. With the turbo you get better midrange power, albeit in a trade off for some lag which you don't have with a supercharger of course. Nice to see you are still developing the 968, just a shame more people are not taking up these fantastic power upgrades for such a great car. If I had to start all over again I may well have chose the SC route, but I never seem to take the easy road!
I am still to refine my Motec M400 that I have fitted to my 968 turbo. If I can't get it how I want it I may give you a call as I havent had much luck with the dyno I used first time round. Before I go back to another dyno I will need to make up a custom intercooler as the 951 IC in the front lower location is not cutting it as well as blocking off the air flow to the rad leading to less than ideal cooling. Apart from that, just chasing down a couple of leaks in the exhaust system and its more or less where I want it.
05-16-2007, 08:18 PM
#14
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Here are the photos of our Porsche Motorsport replica solid flywheel which is a direct replacement fit for the factory dual mass unit, running the stock clutch. This is the prototype with welded on ring gear and trigger ring, on the production units we now shrink fit the rings on. The flywheels are supplied fully balanced ready to fit.