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philly single
06-26-2008, 08:22 AM
MSD 7531
377" sbc, powerglide, 106mm turbo on drag radials....

I'm new to racing this setup and still learning about the MSD box, which has been great so far!

My question is - does anyone at MSD have a suggestion on slew rate or another option to use to try and control the massive wheel speed / spin I get once this turbo spools?

The car launches fine, consistantly 1.32-1.40 and then gets very loose just past the 60' line when the turbo is fully spooled.

Current setting for slew ON:
Gear 1: 3100rpm
Gear 2: 3700rpm

After looking at the log, I see RPM change / sec reaching 5900rpm before the RPM limit/slew comes on. Granted it goes from 3000rpm to 5900rpm in only.05 seconds...so I assume it's working just fine right?

Now, the rpm slew limit stays on (solid line in the log) from .88sec to 1.00sec and I see the rpm change is down to 2900rpm.

BUT...from 1.00 - 1.30sec it's turning on/off rapidly as rpm change bounce around the slew limit...during that whole time the car was def spinning the tires and really all over the track. This was all in first gear.

Question: Is my rpm slew set too high? Should I bring it down to 2500rpm in 1st gear in an attempt to keep things under control?

Or is there another angle to attack this from?

Thanks!
Jay

MSDTECH8
07-08-2008, 08:22 PM
you will need to email me your acquisition file and ign file. In a normal application the first gear slew will be greater than your second gear slew. Please be sure to send me your acquisition file with you optimum run.

philly single
07-09-2008, 10:58 PM
Never mind, I figured it out for myself.

msdtech21
08-20-2008, 10:42 AM
Good to hear.

Thanks,
MSDTECH21