Had my car strapped on the dyno and it kept spinning the tires. Wanted to ask if spinning the tires affect the tune in any way? The guy that tune my car said my A/F was great and that's all that matters, the only thing that spinning the tires changes were my power numbers. Is this true?
Spinning tires on dyno
- Thread starter LETHL 03
- Start date
We have in house Dyno where I work and we see all levels of power on it. Spinning the tires on the drum is unacceptable it skewes all the numbers!!! Depending how badly you were spinning does make a difference. Not sure on how your guy has his anchor points located but we control wheel spin with two anchor points located about two feet or so from the drum. This makes the straps pull down on the axle and the tires into the drum. As far as your AFR being correct I would take what he said with a grain of salt. Get your self a good wideband the innovate MTX wideband is a good choice and monitor the AFR just to be on the safe side.
Dynos are not real great at simulating real world street/strip conditions anyway - the load bearing dynos are better, but nothing beats the dragstrip or road course with wind resistance. That being said, a dyno is the only option to safely tune the car, but when the tires spin excessively the engine does not come close to seeing the load it will see on the street so that will affect the tune somewhat. On turbo cars (yours may not be) it is always a great idea to do a double check of fueling on the street/strip, because often there are differences.
We have been to a lot of places training tuning shops and have seen all kind of setups - the best I have seen by far was a Mustang Dyno in Mettiere, LA - the had a small pit with anchors fabbed right under where the tires would be. They connected straps that pulled straight down on the axles to the anchors - we tuned maybe 10 vehicles, some with crazy power and no hint of wheelspin.
When all else fails when we are doing a session and the tires break loose, there usually are a number of bystanders watching, so we ask for the beefiest volunteers to sit in the trunk - that usually works.
In one session in Oklahoma, we heard a story about a young guy in an import at the dyno who was removing weight from from the trunk of the car. When asked why, he said he always did that at the track and got better times and figured he'd also get better numbers on the dyno doing that.... Hmmmm...
Don LaSota
We have been to a lot of places training tuning shops and have seen all kind of setups - the best I have seen by far was a Mustang Dyno in Mettiere, LA - the had a small pit with anchors fabbed right under where the tires would be. They connected straps that pulled straight down on the axles to the anchors - we tuned maybe 10 vehicles, some with crazy power and no hint of wheelspin.
When all else fails when we are doing a session and the tires break loose, there usually are a number of bystanders watching, so we ask for the beefiest volunteers to sit in the trunk - that usually works.
In one session in Oklahoma, we heard a story about a young guy in an import at the dyno who was removing weight from from the trunk of the car. When asked why, he said he always did that at the track and got better times and figured he'd also get better numbers on the dyno doing that.... Hmmmm...
Don LaSota
Thanks for the info. On the dyno graph, a/f is 11.5 all across
Users who are viewing this thread
