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How many RPMs can she take?

Speedy!

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#41
I can probably name on one hand the tuners I'd trust with my car. Add that to the fact the Hellcat platform has become extremely popular and you can imagine their inboxes stay full. I talk to Mike from OST pretty often and he's 3 weeks behind on email tunes today. Business is good. I'm sure it's the same for Tim.
 


stonewall

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#42
Does anybody have an idea at what Rpm the supercharger rotors would be spinning @ 7,800 rpm's? I guess that you wont be using the stock unit.
 


BULL

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#43
Does anybody have an idea at what Rpm the supercharger rotors would be spinning @ 7,800 rpm's? I guess that you wont be using the stock unit.


7800 / 6200 = ~1.26


So 26% faster...
 


Speedy!

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#44
I've always wanted to create a map with name/locations/recommendations for the members. Some guy that works in the industry ;) and knows how to do that with Google Maps might be a good candidate for that, unfortunatly, that's not me. Know anybody that could do that?
That used to be easy on Google maps, but they don't offer it any longer. Probably a third party way to do it, but more work and upkeep I think than most would sign up for (permissions and such).

7800 / 6200 = ~1.26


So 26% faster...
Or 2.36 (supercharger drive ratio stock) x RPM
2.36 x 7800 = 18,408rpm with the stock supercharger and crank pulleys :)
 


stonewall

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#45
And the stock SC rotor spins @ 25,000 rpm ish at 6200 engine rpm?
 


Speedy!

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#46

cole3986

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#47
Bull,

I was going to let this thread go but you sucked me in. The A8 will not shift above 7,000 rpm. Sure, on a dyno a gear can be held but not going to shift at 7,800 rpm at the track.

I have never blown up a supercharger based on supercharger speed. Blown up 3 blowers using a 250 or 300 nitrous shot.

If the heat generated by spinning the blower causes the PCM to pull timing (typically above 152 F) then it serves no purpose, use an ice tank, IATs drop to under 100 F, additional rpm now is useful, IMO.
 


BULL

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#48
Bull,

I was going to let this thread go but you sucked me in. The A8 will not shift above 7,000 rpm. Sure, on a dyno a gear can be held but not going to shift at 7,800 rpm at the track.

I have never blown up a supercharger based on supercharger speed. Blown up 3 blowers using a 250 or 300 nitrous shot.

If the heat generated by spinning the blower causes the PCM to pull timing (typically above 152 F) then it serves no purpose, use an ice tank, IATs drop to under 100 F, additional rpm now is useful, IMO.

Two things, a sincere thank you for the useful post. (really...)


And I hope you know that my poke was a good-natured poke, and while it was factually wrong, it was still fun to poke at your misfortune, like friends do to each other on occasion....


:)
 


cole3986

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#49
Two things, a sincere thank you for the useful post. (really...)


And I hope you know that my poke was a good-natured poke, and while it was factually wrong, it was still fun to poke at your misfortune, like friends do to each other on occasion....


:)

Bull,

I always try help the Forum out, some more information, never, never, let a E85/E98 hellcat sit for 10 months, ran 9.03 at Eplings event a few weeks ago (on boost), thought, how bad could the injectors be? Almost did not take the injectors out because the cat ran good (1.31 60 foot 3 times), however, the injectors were screwed, they took over 1 week of work, some would not pulse correctly, wow, installing them tomorrow for the MSHS event, looking for 8.7/8.8's on boost, then a small stray for the 8.5 super pro class.

Remove the injectors after the event and have them cleaned, do not make my mistake.

Regarding spinning the motor, keep the shift points below 6,500 rpm because if there is a problem with the command, the cat will bounce off the rev limiter, I lost at least 1 blower bouncing off the shift points, a quick hellcat will cause a delay in the shift command, got to have a buffer or the cat will bounce off the rev limiter, which is not desirable.
 


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Hpindy

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#50
Bull,

I always try help the Forum out, some more information, never, never, let a E85/E98 hellcat sit for 10 months, ran 9.03 at Eplings event a few weeks ago (on boost), thought, how bad could the injectors be? Almost did not take the injectors out because the cat ran good (1.31 60 foot 3 times), however, the injectors were screwed, they took over 1 week of work, some would not pulse correctly, wow, installing them tomorrow for the MSHS event, looking for 8.7/8.8's on boost, then a small stray for the 8.5 super pro class.

Remove the injectors after the event and have them cleaned, do make my mistake.

Regarding spinning the motor, keep the shift points below 6,500 rpm because if there is a problem with the command, the cat will bounce off the rev limiter, I lost at least 1 blower bouncing off the shift points, a quick hellcat will cause a delay in the shift command, got to have a buffer or the cat will bounce off the rev limiter, which is not desirable.
I agree with all of this .

Sent from my BBF100-2 using Tapatalk
 


stonewall

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#51

Hickster

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#52
Don't know but the chillers I was working on McQuay magnetic chillers were running 32,000 and would work on a variable speed drive and would down load to 10%. And still run with no noise. No moving parts so no noise. Wish I could place one of those compressors in the trunk of the H/C. One bad expensive bitch. Drop the tempt to -32 if need be. Works off magnets so it levitates as the load increases and spins. No refrignant oil to worry about and no noise at all.
 


BULL

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#53
Moved various posts to a new thread.
 


BULL

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