Flash RPM?

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NOVALOU
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Flash RPM?

#1 Post by NOVALOU » Thu Sep 26, 2013 6:28 pm

I launch my car at 3500 RPM and the converter flashes to 7000-7200. If I raised the 2 step to 5500 RPM would the converter flash less or more? and by about how much?

This is a Procharged SBC application.

Thanks in advance,

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Craig W.
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Re: Flash RPM?

#2 Post by Craig W. » Thu Sep 26, 2013 8:18 pm

In general, raising the launch rpm will not flash the converter as hard but as with most things, there are a lot of variables that come into play. Trial and error is often the best teacher.
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Re: Flash RPM?

#3 Post by John_Heard » Tue Oct 01, 2013 7:49 am

It'll change how it hits the tire also by changing the launch RPM. Going to hit the tire harder initially with higher RPM

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Re: Flash RPM?

#4 Post by Craig W. » Tue Oct 01, 2013 7:59 am

Flashing to 7000+ has got to be pretty violent. Since you're asking about it, I assume the car doesn't like the converter?
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supernova
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Re: Flash RPM?

#5 Post by supernova » Tue Oct 01, 2013 10:10 am

I would think that the converter is too loose. The rpm is way high at the hit for a Procharged application. I bet it's very violent. I think at would be a lot better if what you saw was 2000 rpm lower than what you are seeing. Your converter being that loose probibly has slippage % so high that it is slowing you car way down.
There is a lot of unknowns here but that is a awfully high flash even with the unknowns.

JMO

Oh and raising the rpm at the launch may not matter because at that high rpm your motor should be close to max power and that's not good at the hit.
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Marty Chance
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Re: Flash RPM?

#6 Post by Marty Chance » Tue Oct 01, 2013 10:37 am

This question has so many variables I would rather look at a data log with you and see if we could point you in a direction that would help your program go faster. The best way to show me your data log is to link our computer screens through www.join.me. Just go to join.me and click on the "start meeting" button then call me.
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NOVALOU
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Re: Flash RPM?

#7 Post by NOVALOU » Wed Oct 02, 2013 9:54 pm

The car actually is very mellow leaving at 3500 RPM. I pull 10* from 3600-7000, so that's another contributing factor to how the car takes off.

I was planning on experiment with launch RPM last time out but had some other mechanical issues that preventing that from happening?

On my friends naturally aspirated car the converter flash is ever so slightly effected by the rpm you flash the converter from.

So, I'm just curious what some of you guys have seen while experimenting with your launch rpm, especially on a boosted application.?

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Re: Flash RPM?

#8 Post by Marty Chance » Thu Oct 03, 2013 7:11 am

this varies from motor to motor greatly. For example i have a motor with 3.750 stroke and changing launch rpm from 3800 to 3900 makes a significant difference but on my 3.500" stroke motor i can vary the launch from 4000-5800 and see very little difference (same blower F1R) so my point is , It is very difficult to give you accurate info on exactly how your car will respond. I recommend you try different things and compare your data and the car will tell you what direction it wants to go. My offer still stands to look at your data with you.
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NOVALOU
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Re: Flash RPM?

#9 Post by NOVALOU » Thu Oct 03, 2013 9:13 pm

Well after speaking with Marty a bit, I'm going to go ahead and put my other stator in my converter, he said it should flash a few hundred rpm less. We feel the one that's in there now is just a little loose for shifting at 7700-7800; I should know for sure pretty soon.

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Re: Flash RPM?

#10 Post by supernova » Fri Oct 25, 2013 8:35 am

Cool! Let's us know how it does. Marty knows his stuff!!!! :mrgreen:
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
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Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

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