Question about dynoing an automatic transmission
Question about dynoing an automatic transmission Hey guys, I'm not sure if this is the right forum to post this in or not but here it goes! I have a stock auto with a 3600 stall in my 99 ss. I just got the motor built, and dynoed the car. They only went up to 6,000 rpm because the car was at 139 mph and they said it was vibrating a lot. They didn't go any higher because of the risk of snapping the input shaft. I think some power was left on the table because of that limitation. Is there anything I can do to stop the vibration and possibility of the input shaft snapping? Like a brace or new crossmember? I'd like to get a new dyno tune at max rpm. Thanks!
What type of trans mount do you have. Polymounts will transfer vibration when nothing is actually wrong.
__________________
I've come down to the assumption that it's the stock mounts. I'm going to get solid motor mounts and a poly trans mount to help stop the vibration. I don't care that the car will vibrate more, I just need the powertrain/driveline vibration gone. The wheels/tires are in balance since they were done recently and I worked at the shop they were done at.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
IMHO, the proper way to deal with a strong vibration is to find the source of it, not suppress it with solid mounts.
There have been plenty of posts here about driveshafts going out of balance. At those speeds a driveshaft that breaks a u-joint can destroy the car and seriously injure the driver. Hence the use of driveshaft loops.
There have been plenty of posts here about driveshafts going out of balance. At those speeds a driveshaft that breaks a u-joint can destroy the car and seriously injure the driver. Hence the use of driveshaft loops.
Not something to take lightly for sure. The driveshaft is the most likely culprit. The stock aluminum shafts are pretty poor in my experience. It might be slightly bent or out of high speed balance.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'
Brett Foote
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei