dyno question

9lives · 25-03-2006, 03:21 PM

Hey, i heard that when your car is on the dyno you can get a better power figure if you put a weight ballast over the rear axle ( in effect, not getting as much lift off)....

Will have my ute on the dyno next week for the first time and im interested to find out ??? anyone heard of this or done it????

Casper · 25-03-2006, 03:31 PM

Other way around. You will get more kw readout if it is not tied down firmly and it lifts onto 1 roller.

nugget378 · 25-03-2006, 04:47 PM

Getting the dyno to read higher like that wont make your car go any better, if you want it to read more just make sure they put it on shootout, they can also fudge it with the keyboard, but youll look silly when you claim ?kw, and get blown away by a car with whatever less kw, when I had my car on last I was shown how by putting it on shootout it miraculously gained 50hp

EvilChief · 25-03-2006, 05:37 PM

i have said it before and i say it again: Dynometers are tuning tools only and the performance read outs are an indicator ONLY!

so cheat the kW as much as you want, but when it comes down to the time at the strip it wont make you look better.

ratter · 26-03-2006, 11:16 AM

If it's wheel spinning on the dyno, placing more weight in it will give a higher reading,

loosening the straps so it rides higher up on the rollers will also give a higher reading, but whats the point in trying to acheive a false figure? as allready mentioned they are ideally a measuring tool for before and after.

FLUB378 · 26-03-2006, 09:05 PM

Quote:

Originally Posted by EvilChief

i have said it before and i say it again: Dynometers are tuning tools only and the performance read outs are an indicator ONLY!

so cheat the kW as much as you want, but when it comes down to the time at the strip it wont make you look better.

Too true, u can't race a dyno! Can't remember what mag it was in but they did a dyno comparison on numerous cars, they put a tube chassis probe on the dyno slicks and all. The car had run deep into the 9's and had pulled about 800hp on engine dyno yet on the chassis dyno only showed 200+HP. This ony proves "EvilChief" comment. My combo on chassis dyno made 661.9RWHP but could be easily smoked by 500HP car if they can put the power on the track.

brenx · 26-03-2006, 09:37 PM

Slicks don't grip on a dyno FLUB378. Hence low reading ;)

EvilChief · 26-03-2006, 11:31 PM

the only dynos you may get a little more consistency from are either axel dynos (ie dynopacs) or engine dynos, as you are able to cut the variables of friction loss and rotational loss, having said that you still need to control environmental factors as well as calibration.

My 2 cents

9lives · 27-03-2006, 10:32 AM

no worries thanks for that.
I dont want a false reading just wanna know the difference before and after my cams and unichip go in. hopefully the straps will be the same tightness for boths runs so i get a consistant figure... will let you know 1/4 times in next few weeks once i get a chance to go to wsid.

superpursuit83 · 27-03-2006, 12:51 PM

Quote:

Originally Posted by 9lives

no worries thanks for that.
I dont want a false reading just wanna know the difference before and after my cams and unichip go in. hopefully the straps will be the same tightness for boths runs so i get a consistant figure... will let you know 1/4 times in next few weeks once i get a chance to go to wsid.

If you want consistency use the same dyno, same operator and make sure the strapping down is the same. This way you should get a reasonable indication of what each mod has done

Rollin · 27-03-2006, 09:22 PM

sneakily put the dyno intake air temp sensor hanging over the rocker cover above the exhaust - it will think your intake air temp reading is like 90+ degrees and you will pick up a stack of hp.

though as others have said above, why bother?