good idea 
well the procharger just exploded last night!
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Originally Posted by Grasshopper
Doing the calculations, it looks like he's spinning it around 6,100 rpm.
I pretty sure the blower is toast, i still havent had a chance to look at it, i will on friday, maybe i'll take some pics of it.
Originally Posted by Grasshopper
No wonder it blew up. It was way overspun. The D1 has a 4.44 gear ratio. Redoing the calculations puts that blower spinning at 68,993 rpm.
That would do it!! 
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From: Germantown, MD
Originally Posted by Grasshopper
No wonder it blew up. It was way overspun. The D1 has a 4.44 gear ratio. Redoing the calculations puts that blower spinning at 68,993 rpm.
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Originally Posted by LittleRedZ
dont know but i was told by ATI and Lonnie That the blower was spinning at 64800 something like that, well that is the pulleys it came from Ati i havent changed anything.
Is your blower maybe a D1SC instead of a D1? That could make a pretty good difference. The D1SC only has a 4.1 gear ratio. That would put the impeller rpm at 63,710, although that would still be overspinning it since the D1SC is only good up to 62,000 rpm.
Last edited by Grasshopper; Jul 7, 2005 at 02:59 PM.
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Blower Speed (D1SC):
(7.65 / 3.2) * 4.1 * 6500 = 63710 RPM
This isn't that bad. As a rule of thumb a typical 2-4% 'flex' loss can be thrown into the mix to give an actual blower speed. It is not a biblical figure, but if you RPM gage the blower you will usually see a discrepancy from the actual blower speed to the calculated blower speed with the actual being a smidge lower (2-4%).
You actual blower speed is probably between 61000 and 62500.....if it is a D1SC.
If it is a D1 with the step up 4.44, then the blower was well overspun, even including a 'flex'.
(7.65 / 3.2) * 4.1 * 6500 = 63710 RPM
This isn't that bad. As a rule of thumb a typical 2-4% 'flex' loss can be thrown into the mix to give an actual blower speed. It is not a biblical figure, but if you RPM gage the blower you will usually see a discrepancy from the actual blower speed to the calculated blower speed with the actual being a smidge lower (2-4%).
You actual blower speed is probably between 61000 and 62500.....if it is a D1SC.
If it is a D1 with the step up 4.44, then the blower was well overspun, even including a 'flex'.
Last edited by NoGo; Jul 7, 2005 at 05:25 PM.
Originally Posted by NoGo
Blower Speed (D1SC):
(7.65 / 3.2) * 4.1 * 6500 = 63710 RPM
This isn't that bad. As a rule of thumb a typical 2-4% 'flex' loss can be thrown into the mix to give an actual blower speed. It is not a biblical figure, but if you RPM gage the blower you will usually see a discrepancy from the actual blower speed to the calculated blower speed with the actual being a smidge lower (2-4%).
You actual blower speed is probably between 61000 and 62500.....if it is a D1SC.
If it is a D1 with the step up 4.44, then the blower was well overspun, even including a 'flex'.
(7.65 / 3.2) * 4.1 * 6500 = 63710 RPM
This isn't that bad. As a rule of thumb a typical 2-4% 'flex' loss can be thrown into the mix to give an actual blower speed. It is not a biblical figure, but if you RPM gage the blower you will usually see a discrepancy from the actual blower speed to the calculated blower speed with the actual being a smidge lower (2-4%).
You actual blower speed is probably between 61000 and 62500.....if it is a D1SC.
If it is a D1 with the step up 4.44, then the blower was well overspun, even including a 'flex'.
It doesn't look like RedZ has a warranty (he hasn't stated he does), but that still doesn't mean he can over-spin the blower. It'll still break.
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Originally Posted by Ponyhntr
That's nice to know, but ProCharger doesn't account for any so-called 'flex'. They use solid numbers-given by the drive/driven*step-up*engine rpm. If using that formula, and it's overspun, then no warranty. Plain and simple.
It doesn't look like RedZ has a warranty (he hasn't stated he does), but that still doesn't mean he can over-spin the blower. It'll still break.
It doesn't look like RedZ has a warranty (he hasn't stated he does), but that still doesn't mean he can over-spin the blower. It'll still break.
Originally Posted by LittleRedZ
3.4 upper and 7.65 lower dosent overspin the blower at 6500rpm, i dont have the 3.2 i messed up
