Victor's Rotrex Supercharger Kit - Group Buy?
09-21-2012, 01:49 PM
#61
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481rwhp minus 326 rwhp is a delta of 155rwhp. 25.83 RWHP per pound of boost (6) almost defies logic. Especially with our stock manifold.
My car dynoed at 280RWHP before adding the turbo. It was not stock. I had an X-pipe ,RMB, advanced cams, EIS intake system, 24 pound inectors, and lots of shark tuning.....
Edit: Not saying it didn't happen, I'm staring at the dyno sheet after all.
Edit edit: My car was dynoed on a dynojet dyno.
My car dynoed at 280RWHP before adding the turbo. It was not stock. I had an X-pipe ,RMB, advanced cams, EIS intake system, 24 pound inectors, and lots of shark tuning.....
Edit: Not saying it didn't happen, I'm staring at the dyno sheet after all.
Edit edit: My car was dynoed on a dynojet dyno.
09-21-2012, 01:57 PM
#62
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09-21-2012, 02:08 PM
#63
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Victor,
I would be a very happy camper with those numbers propelling my S4 motor along irrespective of how they were derived. It would more than compensate for the fact that I do not have a GTS motor in my chassis.
All you chaps who are coming up wth these enhancements are to be commended for giving us punters options irrespective of what route you go. It's not as though you are going to sell thousands of sets and I dare say you will be hard pushed to break even on time invested developing such systems even if your time if priced modestly.
A GB motor is what it is- a work of great artistry/mastery but not sure I see the point in comparing apples and oranges as it were.
As I see it $5k will get you a stage 1 centrif, $10k a TS setup, $15k a twin turbo and whatever the going rate is for a stroker motor these days- presumably $25k and maybe upwards depending on spec and 140 hours [or more?] of build time.
Nowadays we are almost spoiled for choice!
Regards
Fred
I would be a very happy camper with those numbers propelling my S4 motor along irrespective of how they were derived. It would more than compensate for the fact that I do not have a GTS motor in my chassis.
All you chaps who are coming up wth these enhancements are to be commended for giving us punters options irrespective of what route you go. It's not as though you are going to sell thousands of sets and I dare say you will be hard pushed to break even on time invested developing such systems even if your time if priced modestly.
A GB motor is what it is- a work of great artistry/mastery but not sure I see the point in comparing apples and oranges as it were.
As I see it $5k will get you a stage 1 centrif, $10k a TS setup, $15k a twin turbo and whatever the going rate is for a stroker motor these days- presumably $25k and maybe upwards depending on spec and 140 hours [or more?] of build time.
Nowadays we are almost spoiled for choice!
Regards
Fred
09-21-2012, 02:33 PM
#64
Under the Lift
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Coast down calibration should be standard for Mustang. Jim Morton does it with each car. With his dyno, Jeff and I only hit about 279 RWHP with x-pipes. On a Dynapac I got 262 RWHP bone stock and 294 RWHP with the x-pipe, before and after same day, which are more inline with expectations. Anyway, the dyno type, calibration and other dyno operator inputs make a huge difference. My experience is that most Mustang dyno operators have not read most of the user manual. They pop in a few numbers for gear ratios and RPM and go w/o calibrating.
http://www.mustangdyne.com/mustangdy...ers-Manual.pdf
326 RWHP for a stock S4 is very, very optimistic. I don't think anyone has ever reported 50+ RWHP increase just from Sharktuning a stock S4 with slightly bigger injectors or is this common knowledge I somehow missed? I've done enough Sharktuning that I would expect to have run into that before. S3s respond much more to tuning. I've Sharktuned my own S4 stock (and with a Roots blower), and I saw nothing terribly significant when stock and chose to return to stock chips. I've Sharktuned George Suennen's 200+ MPH Vortex supercharged S4 (with stock internals and exhaust except x-pipe) extensively on various dynos and on the road over the last 3 years. Even at 13 PSI boost he doesn't produce 481 RWHP on a Mustang dyno despite what appears to be an very optimized tune, at least with pump gas and methanol/water injection (which is better than with race gas).
This is a nice kit and I'm sure provides a good kick in the pants. The before and after numbers are not really all that important. If you even get 100 RWHP for $4500, be very happy. My old Roots blower produced maybe 85 RWHP net at 6 PSI, and with big rubber, it was terrifyingly quick. Of course, being a Roots, it produced almost all of its torque right off the line.
http://www.mustangdyne.com/mustangdy...ers-Manual.pdf
326 RWHP for a stock S4 is very, very optimistic. I don't think anyone has ever reported 50+ RWHP increase just from Sharktuning a stock S4 with slightly bigger injectors or is this common knowledge I somehow missed? I've done enough Sharktuning that I would expect to have run into that before. S3s respond much more to tuning. I've Sharktuned my own S4 stock (and with a Roots blower), and I saw nothing terribly significant when stock and chose to return to stock chips. I've Sharktuned George Suennen's 200+ MPH Vortex supercharged S4 (with stock internals and exhaust except x-pipe) extensively on various dynos and on the road over the last 3 years. Even at 13 PSI boost he doesn't produce 481 RWHP on a Mustang dyno despite what appears to be an very optimized tune, at least with pump gas and methanol/water injection (which is better than with race gas).
This is a nice kit and I'm sure provides a good kick in the pants. The before and after numbers are not really all that important. If you even get 100 RWHP for $4500, be very happy. My old Roots blower produced maybe 85 RWHP net at 6 PSI, and with big rubber, it was terrifyingly quick. Of course, being a Roots, it produced almost all of its torque right off the line.
09-21-2012, 02:47 PM
#66
No, my dyno numbers are exact....I make them calibrate the thing, each time I go.
I believe that since dyno operators "depend" on people being happy, most all of the other horsepower numbers collected are pretty much pure bull****. (Which is why a 900HP engine can't go over 206mph.) Hell, I know people that will go from dyno to dyno, trying to get the results they want.
The guy that has his dyno "adjusted" to get the "best results" is the guy that gets the return business!
I call these numbers "dream-o-meter" results.
I believe that since dyno operators "depend" on people being happy, most all of the other horsepower numbers collected are pretty much pure bull****. (Which is why a 900HP engine can't go over 206mph.) Hell, I know people that will go from dyno to dyno, trying to get the results they want.
The guy that has his dyno "adjusted" to get the "best results" is the guy that gets the return business!
I call these numbers "dream-o-meter" results.
09-21-2012, 02:54 PM
#67
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Can you post your dyno results?
Dyno chart from 5-26-10. I'm going to try to get back to Superior before Sharktoberfest so I know where we are now:
09-21-2012, 04:38 PM
#70
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It's more than just about money.
A supercharged car requires constant "care".
Mark Anderson said it the best....
"If you want a car that you need to raise the hood and fiddle with, everyday, supercharge it. If you want a car that starts and runs everyday, with completely normal service intervals....buy a stroker."
I've seriously got strokers that we could weld the hood shut for 15,000 mile intervals.
And BTW....25K doesn't even buy the parts required to build a stroker.
These are hand built Porsches, not Pintos.
Devek was building strokers, that didn't run for very long, for about 50K, in 2004!
A supercharged car requires constant "care".
Mark Anderson said it the best....
"If you want a car that you need to raise the hood and fiddle with, everyday, supercharge it. If you want a car that starts and runs everyday, with completely normal service intervals....buy a stroker."
I've seriously got strokers that we could weld the hood shut for 15,000 mile intervals.
And BTW....25K doesn't even buy the parts required to build a stroker.
These are hand built Porsches, not Pintos.
Devek was building strokers, that didn't run for very long, for about 50K, in 2004!
Good to see we are talking the same language and numbers here. I have no doubt the end products are quite different and bolting on extra power is not going to solve the inherent issues these motors appear to have with oiling etc and it sure is not going to improve reliability even if the bolt on bits do no harm to the existing kit.
I tend to view the s/c route as an acceptable alternative for occasional use to liven things up on a street machine. Not so sure I would even want to try one on the track for other than the occasional lap or two on a track day.
No idea what you chaps charge but given a straight forward strip and rebuild is rated by Porsche at 140 hrs and that without specialised mods etc it does not take a whole lot of gumption to recognise that the end product may be in the $50k region assuming $100/hr labour. Such artistry quite reasonably comes with an appropriate price tag so it takes a very motivated owner.
Regards
Fred
09-21-2012, 07:17 PM
#72
Three Wheelin'
Hi Jim,
Victors car is a 5 speed, my understanding is that 270 rwHP is for the automatic cars and the 5 speeds make more.
Victors car is a 5 speed, my understanding is that 270 rwHP is for the automatic cars and the 5 speeds make more.
I hadn't previously focused on the "before" numbers, but this is interesting. An RMB with a stock exhaust is net-zero for added hp, so the only power-adder was 24# injectors and Sharktuning. And power in that configuration was 326 rwhp. A stock S4 will be right around 270 rwhp, so the 24# injectors and Sharktuning is worth another 56 rwhp-- a whopping 21% increase.
That's terrific, and a lot more from injectors and Sharktuning than I think anyone would have guessed, including me. That also confirms what a great investment a Sharktuner is, at only a fraction of the cost of a S/C setup. For more info see http://JDSporsche.com or my website at http://siriuscyber.net/sharktuner.
We can also extrapolate this back to a completely stock car without Sharktuning, compared to a Rotrex setup with standard "safe" tune. Victor's 481 rwhp (from the dyno sheet) compared to 326 (also from the sheet) is +48%, and applying that to a completely stock car at 270 rwhp would be 398 rwhp. That's pretty sweet also!
Cheers,
That's terrific, and a lot more from injectors and Sharktuning than I think anyone would have guessed, including me. That also confirms what a great investment a Sharktuner is, at only a fraction of the cost of a S/C setup. For more info see http://JDSporsche.com or my website at http://siriuscyber.net/sharktuner.
We can also extrapolate this back to a completely stock car without Sharktuning, compared to a Rotrex setup with standard "safe" tune. Victor's 481 rwhp (from the dyno sheet) compared to 326 (also from the sheet) is +48%, and applying that to a completely stock car at 270 rwhp would be 398 rwhp. That's pretty sweet also!
Cheers,
09-21-2012, 07:24 PM
#73
Three Wheelin'
Find me a supercharged 928 engine (with stock internals) that can make 2 laps at Willow Springs, at WOT, and I'll change my entire thought process....until then, everyone is simply installing the fuse to a grenade.
I do know how to find out....Let's run one right next to a known output engine and compare apples with apples.
Hell, I'm "spotting" you guys over 100hp, at the rear wheels and offering to run you heads up!
What is a "known output" engine? I assume you are referring to SAE standards for dynos? What makes you think that only your standards are the only ones that are correct, and everyone else's are inflated?
I'd like to see this done with one of the Murf cars as well. Maybe a stage one AND a stage 3. I'm pretty sure they use SAE correction factors in GB also. At a neutral spot where everyone has to come out of their respective "corners". THAT is when you'll get a legitimate "winner".
09-21-2012, 07:38 PM
#74
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There you have it, straight from one of the professionals.... I know Gregs strokers have great torque and power. I would still take the challenge just for the fun of it though. Esp at $9.28. I think it would be a riot!!! Yes we would probably get torqued off the line, but you can only put so much power to the road before smoking the tires, and if we are both on road tires, that could make quite an interesting white smoke show. I may then have to counter challenge and go for a 40 to 80 run on the highway though
Regaurdless this thread is not supposed to be about who can beat who, or what has the most power, or even whats the limits of the system. There is always someone faster. Look at that damn twin turbo Todd has, now that's 5.0 power... Holy crap!! So let Mike do his thing on this group buy thread, and see if he can get to the numbers he is hoping for to save himself and others some cash. We can always start a "Challenge" or "comparison thread" for this other stuff. And I am more than willing to have a Rotrex thread to answer anyone's questions, concerns, issues, or whatever may come up.
Regaurdless this thread is not supposed to be about who can beat who, or what has the most power, or even whats the limits of the system. There is always someone faster. Look at that damn twin turbo Todd has, now that's 5.0 power... Holy crap!! So let Mike do his thing on this group buy thread, and see if he can get to the numbers he is hoping for to save himself and others some cash. We can always start a "Challenge" or "comparison thread" for this other stuff. And I am more than willing to have a Rotrex thread to answer anyone's questions, concerns, issues, or whatever may come up.
Great price on the kit!! A little boost goes a long way in these cars.
09-21-2012, 07:51 PM
#75
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