Well, kurgan bought one & we used it on his dad's WS6.. And it worked pretty well.. But we want it for our cars to help tune timming. Hopfully it will be good enough.

Thanks,
-Zach

 

You will be ok, my car is just a freak !

If you guys need help to set it up just e-mail me and I will send you the set up of the unit for a wankel rotary.

 

I think i got all the info we need.. But if we need anything i will be droping you a line

Thanks,
-Zach

 

Ok cool, it's just the set up they give on their site for a rotary is wrong, I sent Mike an e-mail stating how the unit needs to be set up and he will be changing the info on his site.

 

I was under the impression that you should do your dyno pulls in 4th gear, since in most trannies, its a 1:1 ratio. That should take care of most of your tire slip... maybe At least give it a try....

 

he's hitting 170kph in 3rd and you think he should try 4th?

Hey rice, sorry for the late update. I have built the prototype and have been having heaps of fun with it. I have done 2 runs so far 1 on a workmate VT commodore. His run was pretty clean maxing out at 3.59m/s^2. The second run was my TT FD rx-7. This was (not surprisingly) a lot shorter run maxing out at 5.59m/s^2. Both were 2nd gear runs. This BTW is proof that it's power that matters here. His measured RW torque was MUCH LOWER than mine even though his flywheel torque is supposed to be equal. The reason of course is that I can run a lot higher diff ratio (4.11 vs 3.08).

The runs looked to be quite noisy but on closer analysis I found out I was measuring the individual power pulses (sampling at @ >500samples/s !

So I've got some averaging software in at the moment but its raining outside

I do have the LED bar graph working so I'm having a ball nailing the throttle and watching the graph

I'll let you know when I have a good smooth power run. I should point out that my system will read your power too low if you have wheelspin but can it's very obvious on the graph what the wheelspin is.

-pete

 

Thanx rpm-pwr, I sent the other unit back, I was not prepared to do power runs in 4th gear and 240+kph !

 

wow, great thread, and RICE, stop changing your mind! ha ha
It would be incredible to get some of this integrated into something like the HKS C.A.M.P. so you could check out your dyno right after you ran it.

rpm_pwr: are you just making this for yourself/small amount of people interested, or are you planning on making quite a few and distributing it?

 

Wow, I am glad I read all that. Lots of good information. Some day when I have the money to get more seriously into this I will definitely be looking for just this kind of thing. Thanks for gicing me a lot to think about tonight.

 

Well. it was originally being made just for me to measure suspension / engine mods. But I have also used the excuse of testing to get a ride in some pretty powerful cars .. and now those people want one...

BTW Update:
More testing shows that the 'overshoot' I saw on gear changes comes from suspension wobble which causes the earth's gravitational field to wobble the signal. A 2002 WRX with a flat 2-3 shift will wobble nearly halfway through third!! My FD with 255 T1=S' and the factory adjustable shocks all round has virtually NO suspension shift at all Not to worry I have a fix (turn the unit sideways and mesure both axes) and development continues...

-pete

-pete