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RPM QUESTION ON GRAPH!
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DRR S/Pro
Picture of Kutsick
posted
What is your opinion on the change in direction of the rpm`s just before the shift?




 
Posts: 526 | Location: Couch | Registered: January 05, 2003Reply With QuoteReport This Post
DRR Top Comp
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Are you talking about the sharp rise in RPM leading up to the shift?


.
Dave



F J B

 
Posts: 4582 | Location: Earth | Registered: February 08, 2006Reply With QuoteReport This Post
DRR S/Pro
Picture of Kutsick
posted Hide Post
Yes.




 
Posts: 526 | Location: Couch | Registered: January 05, 2003Reply With QuoteReport This Post
DRR Pro
Picture of 67TSCHEVY2
posted Hide Post
Overlay the driveshaft rpm
 
Posts: 1265 | Location: middle georgia | Registered: July 20, 2003Reply With QuoteReport This Post
DRR S/Pro
Picture of Kutsick
posted Hide Post
I can not do that. I dont have a racepack with a driveshaft sensor only the grid that just gives me the rpm graph.




 
Posts: 526 | Location: Couch | Registered: January 05, 2003Reply With QuoteReport This Post
DRR Top Comp
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So many things it could be....
It really starts to rpm/pull @7000rpm
"Driving through the convertor"
Tires start spinning
etc etc

You need more data to interpret the graph correctly....


.
Dave



F J B

 
Posts: 4582 | Location: Earth | Registered: February 08, 2006Reply With QuoteReport This Post
DRR S/Pro
Picture of Kutsick
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If you listen to this video interview with Marty Chance at about 30.00 into it he addresses it and says it is a converter problem.




 
Posts: 526 | Location: Couch | Registered: January 05, 2003Reply With QuoteReport This Post



DRR Top Comp
Picture of Curly1
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With limited information we have I would say the converter is too tight and where it ramps up is where motor really gets into powerband.


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Posts: 4352 | Location: United States of Texas | Registered: April 02, 2011Reply With QuoteReport This Post
DRR S/Pro
Picture of Kutsick
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Yes I do believe it is a converter issue, that is why I have already contacted two different converter company's about a new one. Just waiting on a response at the moment.




 
Posts: 526 | Location: Couch | Registered: January 05, 2003Reply With QuoteReport This Post
DRR Pro
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From the graph display, it looks like you are using a distributor to trigger the ignition.
 
Posts: 2722 | Location: 53056 | Registered: December 30, 2009Reply With QuoteReport This Post
DRR All Star
Picture of Scott Smith
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Logging data without a drive shaft sensor is like evaluating a time slip without sixty foot times.
 
Posts: 7021 | Location: Montgomery Al. USA | Registered: October 04, 2001Reply With QuoteReport This Post
DRR Sportsman
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What's your combo?

You are not getting a flat spot indicative stall.

I see this sometimes with Nitrous or blown cars running their "small" tune-up but the "big" converter:


typical Powerglide bracket car:

 
Posts: 675 | Location: New Jersey | Registered: April 26, 2001Reply With QuoteReport This Post
DRR S/Pro
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Most that I see the rpm in low has two curves, your first one is much steeper than most for sure! Most tend to flatten out before the normal steep rise in rpm. How does the Accel curve look? How is it performing on track?

Not a lot to go on here.
 
Posts: 2163 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR S/Pro
Picture of Kutsick
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The best explanation for it that I have heard is in this video at about the 30:00 mark on, where Marty Chance says your losing torque multiplication in the converter. Basically it becomes to efficient/equal. If you have facebook go listen to the explanation here.... https://www.facebook.com/dragi...s/10156383230473588/
 
Posts: 526 | Location: Couch | Registered: January 05, 2003Reply With QuoteReport This Post



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