SC pulley weights?
01-04-2009, 09:55 PM
#26
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Mercedes
I'm saying that the amount of money and time needed to create a new supercharger pulley would not yield enough results to constitute it being beneficial. If you don't believe me, just ask some of the tuners...
01-04-2009, 10:23 PM
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2015 S212
Thanks for the info, Ted and others.
I apologize for the confusion, since I did say SC pulley but meant the crank pulley.
To get back to the original point, I guess I understand that we do not want to reduce the weight from OEM, but what about at least keeping the overdrive ones at that lower weight rather than making them heavier? The reason I ask is because i noticed added lag with the larger pulley. Not throttle lag as the tune took care of that, but lag in engine spin...
I apologize for the confusion, since I did say SC pulley but meant the crank pulley.
To get back to the original point, I guess I understand that we do not want to reduce the weight from OEM, but what about at least keeping the overdrive ones at that lower weight rather than making them heavier? The reason I ask is because i noticed added lag with the larger pulley. Not throttle lag as the tune took care of that, but lag in engine spin...
01-04-2009, 10:43 PM
#28
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01-05-2009, 12:51 AM
#29
Thanks for the info, Ted and others.
I apologize for the confusion, since I did say SC pulley but meant the crank pulley.
To get back to the original point, I guess I understand that we do not want to reduce the weight from OEM, but what about at least keeping the overdrive ones at that lower weight rather than making them heavier? The reason I ask is because i noticed added lag with the larger pulley. Not throttle lag as the tune took care of that, but lag in engine spin...
I apologize for the confusion, since I did say SC pulley but meant the crank pulley.
To get back to the original point, I guess I understand that we do not want to reduce the weight from OEM, but what about at least keeping the overdrive ones at that lower weight rather than making them heavier? The reason I ask is because i noticed added lag with the larger pulley. Not throttle lag as the tune took care of that, but lag in engine spin...
01-05-2009, 01:43 AM
#30
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Any guesses what to watch? I noticed it even before the tune. It has bugged me enough to want to try an EVOSport mid sized pulley. I'm not sure if these huge pulleys really help except at max boost and I like transitional as well.
01-05-2009, 04:15 PM
#32
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I'd be careful, I talk with many high HP supra guys, and on a recent drive one of them had his supra CP fail on him and nearly cost him his engine. Those Supra pulley manufacturers are not producing a very high quality product, most of their pulleys for their market aren't even harmonic dampened. Be very careful who you trust with your engine, most performance companies are not able to produce MB quality performance products. Just a suggestion from someone who has seen some pretty bad product designs from other companies when they've gone wrong.
FWIW, I never like touching crank pulleys. If a tuner would come up with an upgrade to the supercharger pulley for these cars I'd dump my aftermarket unit and go with one of them. I am happy with my VRP unit but I just never liked playing with drive pulleys.
-m
01-05-2009, 04:56 PM
#33
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can't say for sure because I had pulley + TB installed at the same time, but I suspect the larger TB is guilty
01-05-2009, 06:37 PM
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I was a high hp Supra guy (link to my last car - http://www.t04r.com/member.php?show=marcus.frost) and still consider myself one since I know one day I will have another one. You are talking about drastically different platforms and very different variables affecting failures. An engine is an engine but having a high hp 2JZ is very different from a mid-hp M113.
FWIW, I never like touching crank pulleys. If a tuner would come up with an upgrade to the supercharger pulley for these cars I'd dump my aftermarket unit and go with one of them. I am happy with my VRP unit but I just never liked playing with drive pulleys.
-m
FWIW, I never like touching crank pulleys. If a tuner would come up with an upgrade to the supercharger pulley for these cars I'd dump my aftermarket unit and go with one of them. I am happy with my VRP unit but I just never liked playing with drive pulleys.
-m
01-05-2009, 06:43 PM
#35
if by "lag" you mean it just does not rev as freely and feel as lively before, then yes its the mass. If you mean there is an actual delay from when you hit the throttle to when power kicks in that is software.
Only way you can make the car rev more freely in this application (similar to a lightweight flywheel effect) is through mass reduction (power aside, talking about just the character of the engine). The bigger the pulley is, the more its going to weigh and the larger its radius will be. As a result, it will have more inertia. The lightest you could possibly make an overboost pulley is probably around 5.5 lbs (maybe 5.0lbs), anything lower than that and you would probably be pushing the safety envelope. But on stock size, 4.3lbs is a basically what an almost identical Aluminum pulley to the OEM design will weigh. Its very tough to get under 4.3lbs on the 55k pulley simply b/c it has to be a certain size due to the dual belt design. If you want to avoid the heavier overboost pulleys, then just avoid the Hybrid-stock aftermarket pulleys. Go with an all-aftermarket one like VRPs. Although they do not reveal their weight specs on it, I'm sure its at least a little bit lighter than OEM-hybrids (although not as light as ours).
its a trade off really on what you want. This thread does bring up a good point: weight also plays a factor as well as pulley diameter. Obviously the lights pulley w/ the largest diameter will make the most power, but you can only do so much before you start pushing the natural limits of the engine (as some of the 185mm C32 guys have found out... or will in the near future when their engines go kaboom, as some have).
Only way you can make the car rev more freely in this application (similar to a lightweight flywheel effect) is through mass reduction (power aside, talking about just the character of the engine). The bigger the pulley is, the more its going to weigh and the larger its radius will be. As a result, it will have more inertia. The lightest you could possibly make an overboost pulley is probably around 5.5 lbs (maybe 5.0lbs), anything lower than that and you would probably be pushing the safety envelope. But on stock size, 4.3lbs is a basically what an almost identical Aluminum pulley to the OEM design will weigh. Its very tough to get under 4.3lbs on the 55k pulley simply b/c it has to be a certain size due to the dual belt design. If you want to avoid the heavier overboost pulleys, then just avoid the Hybrid-stock aftermarket pulleys. Go with an all-aftermarket one like VRPs. Although they do not reveal their weight specs on it, I'm sure its at least a little bit lighter than OEM-hybrids (although not as light as ours).
its a trade off really on what you want. This thread does bring up a good point: weight also plays a factor as well as pulley diameter. Obviously the lights pulley w/ the largest diameter will make the most power, but you can only do so much before you start pushing the natural limits of the engine (as some of the 185mm C32 guys have found out... or will in the near future when their engines go kaboom, as some have).
Last edited by AMS Performance; 01-05-2009 at 06:45 PM.
