June 23, 2020, 01:41 PM
troyboyracingCar slowed 3 tenths
All new combination, this year. Installed an MSD Grid system (7720 and 7730), new crank trigger and distributor. Car was flawless the first 8 passes of this year, running right where it left off last season. Between rounds, the car loses 3 tenths. Acted like a converter broke, slow to rev and flat on rpm after the shift. Changed converters, went through the fuel system, compression, timing, rotor phase, and such. Looking at the grid playback, shows no timing movement, as it is locked and I do not use the retard feature. Car is consistent enough to race, but still 3 slow. I've read some posts on the 7730 failing and pulling timing. Called MSD and was told to put ground straps on the back of both heads to the chassis, and run power wires directly to the battery. Anyone have some input on this. Thanks
June 23, 2020, 01:45 PM
Mike Rietowquote:
Originally posted by troyboyracing:
All new combination, this year. Installed an MSD Grid system (7720 and 7730), new crank trigger and distributor. Car was flawless the first 8 passes of this year, running right where it left off last season. Between rounds, the car loses 3 tenths. Acted like a converter broke, slow to rev and flat on rpm after the shift. Changed converters, went through the fuel system, compression, timing, rotor phase, and such. Looking at the grid playback, shows no timing movement, as it is locked and I do not use the retard feature. Car is consistent enough to race, but still 3 slow. I've read some posts on the 7730 failing and pulling timing. Called MSD and was told to put ground straps on the back of both heads to the chassis, and run power wires directly to the battery. Anyone have some input on this. Thanks
Put a noise filter on it.
June 23, 2020, 01:46 PM
1320racerquote:
Originally posted by troyboyracing:
All new combination, this year.
running right where it left off last season.
contradictory statement
June 23, 2020, 03:21 PM
troyboyracingSorry, I should have clarified. New combination last August, with 20 passes on it. Grid and crank trigger were installed over the winter.
June 23, 2020, 03:45 PM
Mike RietowKinda sounds like it spun the stator tube. If it seems like it tries to die, when you put it in gear, probably spun the tube.
8 nice laps, then slow down 3 tenths. I'd be thinking more along these lines after changing the converter, possibly. Powerglide
June 23, 2020, 05:03 PM
Mitch HCould be a lot of things.
About 4 years ago I was running my old squarebody pickup truck with an even older 482. Last run of the night I let it get away from me rolling out of the water and buzzed it to 8500rpm. Other guy in the final round broke his transmission, so I just gently drove it down the track, loaded up and collected my check.
Next day at a track one state over the truck is off .29 to the 1/8th. Sounds good, just slow. The darn thing was dead on all day, with 4 rounds total package less than .010
Turned out that I broke three middle springs in that water box deal the night prior.