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krawler - dont know mate u will have to ask them.

it was done at DYNO SOURCE a 4wd dyno and was just be re-calabrated a week before hand.

gavin sayed another one of his gtrs made 617hp on a engine dyno and on the dyno source dyno it made 387hp@awhp

and that car has the works done to it with a HUGE single turbo.

wouldnt mind seeing what it would make on another dyno, prob another 60hp all depends on the dyno and how it reads.

Looks like you had a bit of wheel spin - that's what usually causes the dips and rises.   It's the wheels gripping, then leting go, then gripping etc..

Nothing to be worried about.

J

Well it is something to be worried about actually, if this is what happened, then why didnt gavin tell melv and then dyno again. Surely wheel spin of any kind on the dyno would alter the final results significantly

Well it is something to be worried about actually, if this is what happened, then why didnt gavin tell melv and then dyno again. Surely wheel spin of any kind on the dyno would alter the final results significantly

What I meant was just because the dyno graph is up and down as it is, doesn't particularly mean there is something mechanically wrong with the car.

Only got to 3rd?? Err... Have you seen a dyno work before?

I'm sure there are many good reason as to why Gav did what he did. My car is going down on monday so I'll ask all your demanding questoins then.

Who cares what the graph looks like, it's an awesome power readout that I'm sure melv is happy with.

no erin i have never seen a dyno before fill me in

I think she's probably wondering the same thing I'm wondering... What do you mean "Only got to 3rd"?

Normally dyno runs are done in 4th gear. Thats because it is 1:1 (or at least, the closest to. I dont think all cars are actually 1:1) and gives you the most accurate estimate of HP cause you dont get the torque multiplication you get with lower gears.

So when you said "Only got to 3rd gear", it sounds like you are thinking that he revved out 1st, revved out 2nd, revved out 3rd and then gave up? I dunno, you're crazy as a coconut :headspin:

And the other thing I was wondering was why the curve has all the blips. Apparently due to RWD swapping to FWD as it lost traction (yay GTR!) but I was thinking if thats on an AWD dyno, that shouldnt happen... Unless the HP is only actually measured on the rear set of rollers and the fronts are just there so the front wheels dont just do some 200k/hour static burnout on the concrete? I dunno enough about dynos :rant: Anyway, if thats the explanation than I'm a bloody jenios (nb - you are still crazy as a coconut :headspin: ) :)

I think she's probably wondering the same thing I'm wondering... What do you mean "Only got to 3rd"?

 

Normally dyno runs are done in 4th gear. Thats because it is 1:1 (or at least, the closest to. I dont think all cars are actually 1:1) and gives you the most accurate estimate of HP cause you dont get the torque multiplication you get with lower gears.

 

So when you said "Only got to 3rd gear", it sounds like you are thinking that he revved out 1st, revved out 2nd, revved out 3rd and then gave up? I dunno, you're crazy as a coconut :headspin:  

 

I would think that there was a calculation done to account for the fact that it was done in 3rd and not 4th. There was no doubt a good reason for this!

Mindflux, a cars power isnt determined by the top gear at top rpm! by the sounds of things thats what you thought...by saying it only got to 3rd....

Nice figure, but I do wonder about it being done in 3rd not 4th. Also i doubt those dips are wheel spin just friday i ran my cefiro up on the dyno and thats rwd and it didnt have any of those dips.. Nice figure though :)

suprised power delivery isnt that broad though seems pretty peaky, mite be due to the gearing though

Wheel spin is very possible on a dyno. It depends on the ramp rate used and the power of the car (not to mention the grip on the tyres).

If the ramp rate is slow, it may tend to spin a little. Happend when I had my car on the dyno, and then again with a R32 GTR when I was there.

I wouldn't say it is common, but it does happen.

J

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