[Warning: M.net content] Turbos make more power but superchargers make more 'torque'
#81
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Here is my post on the matter in which I discuss throttle nonlinearity in NA motors. IMO it's an important concept to understand.
MX-5 Miata Forum - View Single Post - old TC vs SC debate...
Hey Sav, how do you think a 220 hp GT2554 setup would compare to a 220 hp s/c setup on the track?
MX-5 Miata Forum - View Single Post - old TC vs SC debate...
Hey Sav, how do you think a 220 hp GT2554 setup would compare to a 220 hp s/c setup on the track?
Julian, what kind of experience does sjmarcy have? I thought he was a fanboi who might have a little experience, but after his "drifting is not performance driving" comment I have basically no respect for his commentary. To me, he sounds like a guy who has NEVER driven a big turbo car, or if he has driven it he hasn't done it fast. People who don't have the experience/skill/both to extract the potential from a 28R/30R sized turbo will obviously badmouth it and say it's slow, when in reality it's the nut behind the wheel that needs adjustment.
#82
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seems like he has plenty of experience...back in 1980 before he retired and bought a lotus and plays with his accelerometer all day long.
the rotrex needs a transmission module to get full boot earlier.
the rotrex needs a transmission module to get full boot earlier.
#84
You know, I forgot to mention since people feel that Henessey vipers, Kon. Cars, Bugatti Veyrons, etc are great examples of turbo vs. supercharger debates...
How come nobody mentioned the massive dominance of Turbochargers for over a decade until their ban in Formula One? I mean, turbos running upwards of 40psi with water/toluene as gas? Are you kidding me? Anyway, they basically cleaned the floor with any other sort of competition at the time, and F1 cars had their highest power/speed levels around that time. Its sort of come down back to earth and started to rise, obviously, since then, but I'm sure it was a hell of a time to be an F1 driver.
How come nobody mentioned the massive dominance of Turbochargers for over a decade until their ban in Formula One? I mean, turbos running upwards of 40psi with water/toluene as gas? Are you kidding me? Anyway, they basically cleaned the floor with any other sort of competition at the time, and F1 cars had their highest power/speed levels around that time. Its sort of come down back to earth and started to rise, obviously, since then, but I'm sure it was a hell of a time to be an F1 driver.
#85
How come nobody mentioned the massive dominance of Turbochargers for over a decade until their ban in Formula One? I mean, turbos running upwards of 40psi with water/toluene as gas? Are you kidding me? Anyway, they basically cleaned the floor with any other sort of competition at the time, and F1 cars had their highest power/speed levels around that time. Its sort of come down back to earth and started to rise, obviously, since then, but I'm sure it was a hell of a time to be an F1 driver.
Other than drag racing, what other forms of racing allow/encourage supercharger use? I know there's got to be others, but I'm blanking.
#86
I'm not sure how relevant it is to the debate for a street car looking for some extra power, but it's an interesting question. Obviously turbocharging is massively popular in almost every series where it's allowed.
Other than drag racing, what other forms of racing allow/encourage supercharger use? I know there's got to be others, but I'm blanking.
Other than drag racing, what other forms of racing allow/encourage supercharger use? I know there's got to be others, but I'm blanking.
#87
Julian, what kind of experience does sjmarcy have? I thought he was a fanboi who might have a little experience, but after his "drifting is not performance driving" comment I have basically no respect for his commentary. To me, he sounds like a guy who has NEVER driven a big turbo car, or if he has driven it he hasn't done it fast. People who don't have the experience/skill/both to extract the potential from a 28R/30R sized turbo will obviously badmouth it and say it's slow, when in reality it's the nut behind the wheel that needs adjustment.
I've missed the "drifting" comments - maybe he's part of those "elitist" groups who hate drifters
Last edited by j_man; 02-23-2010 at 04:02 PM.
#88
Depends entirely on the track. I think a Rotrex might have a slight edge on a fast track, but the 2554R is going to produce a lot more torque lower down, which means that on a tighter track (i.e. autocross, Streets of Willow, etc) it probably will have a slight advantage.
2554 = more low end, less top end
2560 = about par
2860 = less low end, more top end
And comparing the Rotrex to a turbo is much closer to comparing apples/apples than comparing turbos to a PD supercharger... since as I said before it's basically a belt driven turbo.
Last edited by Rennkafer; 02-23-2010 at 08:31 PM.
#93
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it still makes boost with rpm rise like all SCers. you'd need to run it completely unrestricted and then close a restrictor with rpm increase so it would output boost like a turbo if I understand it's operation correctly
#94
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Ive always been confused why they run it that way.
Ive seen other centrifugal supercharger setups that use a bypass system, so that you can use a ratio that builds boost much faster and then maintains it at that level, like a wastegate.
So instead of making 10psi at redline make 10psi from 4k-redline.
I recall asking emelio about this when he initially posted the kit on M.net but he didnt seem to understand what I meant.
After a quick search on the interwebz, I found this,
I give you exibit A:
The blue line is running the supercharger in its normal configuration, the red line is with a boost controlling bypass valve.
Ive seen other centrifugal supercharger setups that use a bypass system, so that you can use a ratio that builds boost much faster and then maintains it at that level, like a wastegate.
So instead of making 10psi at redline make 10psi from 4k-redline.
I recall asking emelio about this when he initially posted the kit on M.net but he didnt seem to understand what I meant.
After a quick search on the interwebz, I found this,
I give you exibit A:
The blue line is running the supercharger in its normal configuration, the red line is with a boost controlling bypass valve.
#97
So much like a wastegate, except it byasses intake air charge instead of exhaust gases. I guess there would not be a loss of efficiency since the compressor will simply spin at tht RPM it spins at as opposed to spining faster and faster. probably a lot cheaper and more reliable than a variable planetary gear set.
#98
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exactly
it was a proof of concept not a real application
but I know there are kits sold like that because I used to know a guy with such a setup on his mustang GT, he would make like 10psi almost immediately and it would 'creep' to 12 at redline.
You could take a rotex kit and just add a normal wastegate onto the charge pipe to bleed off boost. Then just use the right pulley ratio to spin it as high as you safely can.
it was a proof of concept not a real application
but I know there are kits sold like that because I used to know a guy with such a setup on his mustang GT, he would make like 10psi almost immediately and it would 'creep' to 12 at redline.
You could take a rotex kit and just add a normal wastegate onto the charge pipe to bleed off boost. Then just use the right pulley ratio to spin it as high as you safely can.
#99
Sounds like a pain in the butt to get turbo like results, but i think rotrex's are cool. You can't tell me this isn't cool.
A Sucker's Bet - '72 Nova - Hot Rod Magazine
A Sucker's Bet - '72 Nova - Hot Rod Magazine
#100
exactly
it was a proof of concept not a real application
but I know there are kits sold like that because I used to know a guy with such a setup on his mustang GT, he would make like 10psi almost immediately and it would 'creep' to 12 at redline.
You could take a rotex kit and just add a normal wastegate onto the charge pipe to bleed off boost. Then just use the right pulley ratio to spin it as high as you safely can.
it was a proof of concept not a real application
but I know there are kits sold like that because I used to know a guy with such a setup on his mustang GT, he would make like 10psi almost immediately and it would 'creep' to 12 at redline.
You could take a rotex kit and just add a normal wastegate onto the charge pipe to bleed off boost. Then just use the right pulley ratio to spin it as high as you safely can.
wwwwwwwwWHHHHHHHHHRRRRRRRRRRRRRRQUAAAAAAAAAAAAAAAA AA!
Sweet.