968 Supercharger Kit Development
10-19-2010, 06:56 PM
#901
Three Wheelin'
I suppose I should respond... all I have to look at (like you) are those two photos.
Remember our kit fits without any modification to the car also. This thread has taken a turn into the racing application and away from the street install - but no modification to the car is required for a street install.
Remember that you are comparing a currently available kit with one that is either no longer produced or never was. There are a number of home-built elements in those photographs that make me beleive it was a hand-made and very low production kit.
As to "awaiting CARB certification" - probably not. If the $10,000 to $30,000 CARB certification fees dont get you (Divide $10k by 10 kits and see what that will do you your per-kit price). And thats the filing fee. More CARB fees come later. Generally speaking, unless you can sell 1000+ units, CARB certification just doesnt make sense. Look at the Edelbrock manifold website - CARB certification just doesnt make financial sense on any but the most common highest volume units.
The picture shown is using a very small Rotrex supercharger (look how small the volute is), which, when you compare to the size of our volute - will help you know which will make more HP.
Observe the oil lines and know that this install requires oil lines to and from the supercharger. It will run hotter as a result (the motor oil will pre-heat the supercharger case as it passes thru) and possibly should have an intercooler. The installation will also be more complex as a result.
I can also see from the photo that the induction tubing makes a large jump in size right at the inlet to the throttle body. Thats a bad idea, and will put flat-spots in the throttle response.
Just a few observations that I was frankly reluctant to make at all. It looks like a well-made, hand-made kit. But, if it is not commercially available, the comparison is rendered moot.
Remember our kit fits without any modification to the car also. This thread has taken a turn into the racing application and away from the street install - but no modification to the car is required for a street install.
Remember that you are comparing a currently available kit with one that is either no longer produced or never was. There are a number of home-built elements in those photographs that make me beleive it was a hand-made and very low production kit.
As to "awaiting CARB certification" - probably not. If the $10,000 to $30,000 CARB certification fees dont get you (Divide $10k by 10 kits and see what that will do you your per-kit price). And thats the filing fee. More CARB fees come later. Generally speaking, unless you can sell 1000+ units, CARB certification just doesnt make sense. Look at the Edelbrock manifold website - CARB certification just doesnt make financial sense on any but the most common highest volume units.
The picture shown is using a very small Rotrex supercharger (look how small the volute is), which, when you compare to the size of our volute - will help you know which will make more HP.
Observe the oil lines and know that this install requires oil lines to and from the supercharger. It will run hotter as a result (the motor oil will pre-heat the supercharger case as it passes thru) and possibly should have an intercooler. The installation will also be more complex as a result.
I can also see from the photo that the induction tubing makes a large jump in size right at the inlet to the throttle body. Thats a bad idea, and will put flat-spots in the throttle response.
Just a few observations that I was frankly reluctant to make at all. It looks like a well-made, hand-made kit. But, if it is not commercially available, the comparison is rendered moot.
To everyone else: Anyone else of the opinion that with mods (eg suspension, engine), you often get best results by prioritising in this order?:
1. Suitability
2. Setup
3. Support
4. Shiny bits (hardware)
IMHO, its far too easy to focus on the shiny bits (item 4). Human nature I guess.
I don't think anyone can expect to better Carl's kit on points 1,2 and 3. And, as an engineer, I really like the way Carl clearly laid out the objectives first before deciding the solution.
Just my $0.02.
Mike
Last edited by mikey_audiogeek; 10-20-2010 at 10:04 PM.
10-19-2010, 07:12 PM
#902
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Very nice. Carl, please accept my apologies. It was not my intention to violate a sponsored thread. I saw a really good installation and posted it on relevant thread, unaware that it was commercially sponsored. I am NOT a competitor and meant no intrusion. My last response was simply to refute some erroneous claims about my post. If I'd taken the time to research the origin of the thread, I would not have posted to it as, as you mentioned, it is very bad form, especially if I were a competitor.
Odurandina... show a little class and send a PM before you publicly slam another member or go whining to the admins. I've never deliberately violated a TOS and this was just an oversight on my part. Keep posting as long as the rest of us have and you'll make mistakes once or twice.
Odurandina... show a little class and send a PM before you publicly slam another member or go whining to the admins. I've never deliberately violated a TOS and this was just an oversight on my part. Keep posting as long as the rest of us have and you'll make mistakes once or twice.
10-19-2010, 08:13 PM
#903
Team Owner
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i deleted....
on a more positive note, today i purchased two very hard to source, Audi S4 2.7 twin-turbo 01E 300 045G - 5th and 6th gearsets... w/ 5th perfect, 0.806, and 6th: 0.684 gears.... and what made it really special was
that i paid for only 400 dollars for the 2 gearsets ! (good things come w/ over a year waiting) !!
these two sets will set you back almost two grand from the dealer,
and it's almost impossible to get people to part the transmissions for their fertile gearsets...
http://www.autoshoppingcenter.com/Vo...sionscode.html
audi ratios table: http://www.elektro.com/~audi/01E/
win for the seller as he gets to keep the box for a customer who wants it for installing shorter track gears...
these are basically the most usefull gearsets that will swap into the stock 968 box for supercharger,
turbo and LSx projects and 175-190 mph top speeds.
5th gear becomes a very usable highway gear, quite a bit taller than the stock 968 5th gear and will take the car easily to 80~120 mph (about 150 at redline ?) before changing to top gear and 6th tops out at about 180 mph at 6000 rpm for running the 275-35-18 tire....
don't yet have the horsepower to make use of the gears. but sometime in the future as i now have a fresh transmission on the side w/ only 48 k miles for installing the gears. or i can use my existing box and do a full rebuild.
/
on a more positive note, today i purchased two very hard to source, Audi S4 2.7 twin-turbo 01E 300 045G - 5th and 6th gearsets... w/ 5th perfect, 0.806, and 6th: 0.684 gears.... and what made it really special was
that i paid for only 400 dollars for the 2 gearsets ! (good things come w/ over a year waiting) !!
these two sets will set you back almost two grand from the dealer,
and it's almost impossible to get people to part the transmissions for their fertile gearsets...
http://www.autoshoppingcenter.com/Vo...sionscode.html
audi ratios table: http://www.elektro.com/~audi/01E/
win for the seller as he gets to keep the box for a customer who wants it for installing shorter track gears...
these are basically the most usefull gearsets that will swap into the stock 968 box for supercharger,
turbo and LSx projects and 175-190 mph top speeds.
5th gear becomes a very usable highway gear, quite a bit taller than the stock 968 5th gear and will take the car easily to 80~120 mph (about 150 at redline ?) before changing to top gear and 6th tops out at about 180 mph at 6000 rpm for running the 275-35-18 tire....
don't yet have the horsepower to make use of the gears. but sometime in the future as i now have a fresh transmission on the side w/ only 48 k miles for installing the gears. or i can use my existing box and do a full rebuild.
/
Last edited by odurandina; 10-19-2010 at 09:32 PM.
10-19-2010, 08:16 PM
#904
Developer
Thread Starter
Miles,
Thank you for writing. Thats a rare and honest fella that posts a retraction. Your fine. No worries. There have been some troubles with a certain 968 parts vendor that likes to rip off designs and call it there own and take credit for it. Its happened enough that members of the forum are very wary of it. I think what happened here is they felt you "accidently" saw one of these installs, when in reality it was a thinly veiled attempt by those guys to edge in again.
As to California, I sell both Ferrari and Porsche 928 kits into CA, none of which are CARB certified. We design the kit so that the supercharger comes off with just a few bolts (three for the 928) - they go get their 2-year sticker, and come home and put it back on.
As we do not move or remove the emissions equipment, they dont have a problem.
Thank you for writing. Thats a rare and honest fella that posts a retraction. Your fine. No worries. There have been some troubles with a certain 968 parts vendor that likes to rip off designs and call it there own and take credit for it. Its happened enough that members of the forum are very wary of it. I think what happened here is they felt you "accidently" saw one of these installs, when in reality it was a thinly veiled attempt by those guys to edge in again.
As to California, I sell both Ferrari and Porsche 928 kits into CA, none of which are CARB certified. We design the kit so that the supercharger comes off with just a few bolts (three for the 928) - they go get their 2-year sticker, and come home and put it back on.
As we do not move or remove the emissions equipment, they dont have a problem.
10-20-2010, 06:28 AM
#905
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+1,Mike
there was no intention at all to ''SPAM'' as someone put it,it was an honest
observation and an enquiry due to lack of available info .
Carl,from the very beginning you have clearly stated your goals,very honestly
and you have also welcomed realistic feedback from other members,on this
venture.You have achieved quite a reputation,in my book anyway ,to
defend your turf with technical , professional and polite statements.,for
the other members to consider and judge for themselves.
After all ,admitedly , the reference to a gear set as a substitute to a supercharger was perhaps not
appropriate on this thread,although by own admission the member who did
made these comments went that road instead of buying a supercharger from you ,but in the words of someone,we progress and mature
through default.
there was no intention at all to ''SPAM'' as someone put it,it was an honest
observation and an enquiry due to lack of available info .
Carl,from the very beginning you have clearly stated your goals,very honestly
and you have also welcomed realistic feedback from other members,on this
venture.You have achieved quite a reputation,in my book anyway ,to
defend your turf with technical , professional and polite statements.,for
the other members to consider and judge for themselves.
After all ,admitedly , the reference to a gear set as a substitute to a supercharger was perhaps not
appropriate on this thread,although by own admission the member who did
made these comments went that road instead of buying a supercharger from you ,but in the words of someone,we progress and mature
through default.
10-20-2010, 11:46 AM
#906
Team Owner
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there are a couple of reasons why i'm not yet, running Carl's supercharger in my car. but i can assure you, none are for a lack of "want" as my car had been running a deficit for a long time on some other issues that had to be addressed first. i daily drive my car pretty far from home at times, and i'll top over 30 k miles this year. so what happens ? more stuff comes up, lol.
about running a transmission that more closely mimics the rare 968 Turbo S box for the street,
there's a good thread we had recently about that, which you in fact started.... https://rennlist.com/forums/968-foru...ar-ratios.html
there probably is no "right" or "wrong" when it comes to gears if you're running a forced induction system (or a V8).
you can run a supercharger without doing anything to the stock 968 box, in fact, what you end up with, is a very fast 0-150-0 car.
(Carl offers a 928 GTS brake kit that compliments the supercharger nicely).
however, once you're running with the increased power on the highway, like, say going about 90 mph.... once switching to the taller gear/s, with the .068 gear, you'll be dropping the rpm down from 36~3700 down to about 3000... you'd also be able to enter into a rather elite class of P-car by having your top end going past 170 mph... not saying anyone should drive like that. not saying this is "where it's at," either, but that's how Porsche builds the Cayman S, 911 Turbo, etc. (to go fast and to spread the gears out over a workable system to maximum speed).
additionally, by installing the correct 5th gear you would still have the first 4 gears for brutal acceleration, but you'd also have the correct 4th and 5th gears for proper highway acceleration up to about 140~150 mph, or simply changing to 6th gear at any point along the way...
you wouldn't want to be installing the higher gear to the box without creating the need for it first. Porsche selected very carefully, the proper gears for the 968, and the result of changing 6th gear while running the stock engine, wouldn't offer an advantage under any circumstances.
we had a gentleman on the following thread adding that taller audi gear to his transmission without having a proper engine to run that gear much less be able to go much faster than about 100 mph in top gear. the other problem is that he will now find himself using his short 5th gear just to go up mild incline on the highway and rely on that gear much more often than he would ordinarily want.
the net savings on rpm is effectively cancelled out for lack of the proper gear to transition from the short 5th to the ultra-long 6th. as explained in the following thread;
https://rennlist.com/forums/968-foru...ar-ratios.html
Shorter? I've always wanted taller. The first few gears are short enough, and then cruising at 75 in 6th, the engine speed is way too high. Our 928 S4 is revving at 2000 rpm at about 70 - 75mph.
odurandina, please tell me more about the taller 5th and 6th gears available from Audi. I'd like to get these gears. PM me if you think that's more appropriate....
odurandina, please tell me more about the taller 5th and 6th gears available from Audi. I'd like to get these gears. PM me if you think that's more appropriate....
10-20-2010, 12:48 PM
#907
Addict
Lifetime Rennlist
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Lifetime Rennlist
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Quality, Performance, Price. Pick any two.
Well done Carl. I'm saving my pennies.
Well done Carl. I'm saving my pennies.
10-23-2010, 03:27 PM
#908
Finally got hold of an a/c compressor. Fitted it, but was unable to open it up to remove the insides, could`nt fathom it out, tried a bearing puller on the pulley and shaft, but nearly wrecked the pulley, so had to install it complete. The belt tension is now super tight, thought the car would`nt run and felt like it was going to sieze, with the a/f ratio meter, going off the scale to lean and not moving, felt like fuel starvation on a short run, stalling, backfiring, etc; Tried tweaking the FMU, to no avail. Fitted the supplied injectors and it got worse, with over fuelling/black smoke from the exhaust, wound out the FMU and still no better. Removed them and fitted the OEM injectors and it ran a bit better but not much, going to stall all the time and running lean, the supllied injectors won`t work, ever 
I have a track day Tuesday, so have to get this sorted.
It goes on
I have a track day Tuesday, so have to get this sorted.
It goes on
10-23-2010, 03:39 PM
#909
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Finally got hold of an a/c compressor. Fitted it, but was unable to open it up to remove the insides, could`nt fathom it out, tried a bearing puller on the pulley and shaft, but nearly wrecked the pulley, so had to install it complete. The belt tension is now super tight, thought the car would`nt run and felt like it was going to sieze, with the a/f ratio meter, going off the scale to lean and not moving, felt like fuel starvation on a short run, stalling, backfiring, etc; Tried tweaking the FMU, to no avail. Fitted the supplied injectors and it got worse, with over fuelling/black smoke from the exhaust, wound out the FMU and still no better. Removed them and fitted the OEM injectors and it ran a bit better but not much, going to stall all the time and running lean, the supllied injectors won`t work, ever
I have a track day Tuesday, so have to get this sorted.
It goes on
I have a track day Tuesday, so have to get this sorted.
It goes on
Fraser.
Last edited by FraMac; 10-23-2010 at 03:40 PM. Reason: can't tpye
10-23-2010, 05:07 PM
#910
Developer
Thread Starter
Edz - you dont have the MAF installed backwards, do you? Silly I know - but make sure the air flow is in the direction of the arrow cast into the cover...
10-23-2010, 05:30 PM
#911
No, the MAF is definately on the right way round
The car has been running fine until now, done around 400 miles,a dyno run and a track day, but now seems reluctant to idle
Frazer, at the PCGB event @ Oulton Park, this Tuesday. I hope
The car has been running fine until now, done around 400 miles,a dyno run and a track day, but now seems reluctant to idle
Frazer, at the PCGB event @ Oulton Park, this Tuesday. I hope
10-23-2010, 06:00 PM
#912
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10-23-2010, 07:50 PM
#913
Nordschleife Master
Just an FYI since a few of you have asked, I just put a fuel pressure gauge on the car and at idle it sits right at 50 psi with the new Welbro 392 installed.
Chris, sorry to hear about your troubles, but I can't figure out why you are so lean all of a sudden. As you said, you have run before just fine. Without the belt slipping you will be getting much more air so I might understand it going a bit leaner than before, but not much and only at the upper RPMs
My replacement pulley arrived in the mail today and is installed. I will be putting the SC back in the car tomorrow.
Chris, sorry to hear about your troubles, but I can't figure out why you are so lean all of a sudden. As you said, you have run before just fine. Without the belt slipping you will be getting much more air so I might understand it going a bit leaner than before, but not much and only at the upper RPMs
My replacement pulley arrived in the mail today and is installed. I will be putting the SC back in the car tomorrow.
Last edited by Lemming; 10-23-2010 at 08:10 PM.
10-24-2010, 06:29 AM
#914
My fuel rail gauge, sits at 58PSI at idle, revving it I can get it swooping to 70 PSI, but backing the FMU off I can control the idle at around 56 and get it to only reach 60 under load