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If you strap it loose and let the tyres up on the front rollers,

you will get a higher reading:), this trick has been proven many times

in dyno comps before here and interstate. You can apparently also overspeed the dyno by getting it

up on the front roller and let it wheelsping hard on it and get a fudged figure aswell with big power cars

I'm confused, why would you get more traction on the front roller, there is more surface area when you car

is on both rollers! the same reason you tyres get a lot hotter! they are actually touching something!

-The rear rollers arn't even connected to the front rollers, so how is there any extra traction? traction is simple, there is a coefficient of friction between the tyre and the roller, and a normal force on the tyre, times these together gives your frictional force. For simplicity, say the normal forces from front and rear rollers on the tyre are the same, as the front roller is the only one that is driven (or retarded by the retarders) friction will be halved compared to having the tyre ride up onto the front roller only as there is only the one normal force on the front rollers. (halving the traction is not exactly correct but good enough for the example)

-A dyno just measures how fast you accelerate the rollers, it knows the inertia of the rollers, factoring in what ramp rate is used then it can calculate power. I'm not sure how having a tyre spin on the roller will actually make the roller "overspeed" but that is not possible. I mean going by this does it mean if I wheel spin on the road I will move faster then if I was not wheel spinning? Don't think so.

Interesting...I just had my car dyno'd today and made 168.5RWKW on a 32 RB20DET with 14psi, fuel pump, with around 11.5 AFR etc etc usual mods, and it seems around the money for what the car has done to it. And yeah i have also heard that shauns dyno does tend to read lower figures in general than some other dynos but as people keep on saying it is easy to fudge the figures.

my 2c.

Edited by R32Abuser

has anyone considered that Hitek dosent fudge figures, but John does know how to strap you car on properly.

i know you all love shaun, but maybe he doesnt know any different so he keeps doing the same thing wrong.

and whoever said he can tune PFC cars quicker with a hand controller then with the laptop.

I cant see how thats possible..

yes he's a nice guy, But at the end of the day your not taking the car to your mates place, your taking it to a professional to get it tuned to its optimal performance and fuel economy throughout the whole rev range.

has anyone considered that Hitek dosent fudge figures, but John does know how to strap you car on properly.

i know you all love shaun, but maybe he doesnt know any different so he keeps doing the same thing wrong.

and whoever said he can tune PFC cars quicker with a hand controller then with the laptop.

I cant see how thats possible..

yes he's a nice guy, But at the end of the day your not taking the car to your mates place, your taking it to a professional to get it tuned to its optimal performance and fuel economy throughout the whole rev range.

no one said they fudge figures. Im sure their is a correct and incorrect way to strap a car on, and as long as my car doesnt come flying off im fine with it.

I said before shaun used to prefer using the hc over the lappie, but i havent spoken to him since he aquired the datalogit. Its all personal preference.

Shaun is a professional in what i want done with my car. Im not a dyno whore. I take my car to shaun for a quick tune - a quick tune.

Its not on the rollers for as long as u say "to get the tyres sticky" Its on their long enough to check afrs, and give it a quick going over. If i wanted more id ask for it. Everytime ive come back from a tune with Shaun the car has felt great, and used less petrol, and knock was minimal.

Im happy. So are you. everyone wins.

I use Shaun because yeh he's a nice guy and gives you the time of day, he's local, many mates use him, and he has a proven record(not that others don't) You will NEVER see any of my cars a Tillbrooks, because i have heard way too many stories about them, and as for all the Keen brothers, ATS i would go too, and the others, well Bill is getting better i hear!

Besides i'd rather my car be tuned safe and at a lower reading than a tuner "tweak" a dyno to make me think he's done a great job so i return to them!

But hey thats my 2c, take it or leave it, i'm not fussed!

Edited by Deluxe

Darren,

Yep supermod it is. An Admin gave myself and 2 others supermod rights that gives us mod abilities in all sections of the forum instead of just the given sections.

Will come in handy as in the past late at night I've came across a few spammers etc in other sections that I haven't been able to do a thing about.

------

I've always gone to Shaun as I've known him since he was rubbing shoulders back at RPM with Tim and Ivan.

He does good by me, never charged me the earth and has a solid track record with a handfull of std RB's pushing 300rwkw and holding together.

I'm aware the dyno days do show a few inconsistent readouts but that honestly doesn't bother me as I've had my car on Shauns dyno many times prior and it always reads the same. I haven't had it on at a dyno day so I have no idea if it would read the same then; possibly not as its usually strapped down by some one different.

Thats all that really matters to me. :P

It would be interesting to hold the next dyno day at Hitek dyno.

Why not.. :D

my car will be going to shaun once i get my pfc/hi flow. i'll be chasing your numbers darren. hehe but as with everything, price is always a factor despite the 'you get what you pay for' moto. so in saying that, how much does boostworx charge usually...

my car will be going to shaun once i get my pfc/hi flow. i'll be chasing your numbers darren. hehe but as with everything, price is always a factor despite the 'you get what you pay for' moto. so in saying that, how much does boostworx charge usually...

forgive me if im wrong from memory $160 for a full tune and runs until he is happy

my car will be going to shaun once i get my pfc/hi flow.

Hmmmm, This means you wanna keep it now then Duc, I like what i hear! as for how much for the full re-tune is i think it MAX $400 or $450, but prob won't even be that much, we will go see him when you get your goodies! :P

Hmmmm, This means you wanna keep it now then Duc, I like what i hear! as for how much for the full re-tune is i think it MAX $400 or $450, but prob won't even be that much, we will go see him when you get your goodies! :)

Yeah mate. Ive worked out the numbers and if I 'upgraded' it would leave me living off rice and soy sauce for a few months+years which I dont want to do. That and the fact that at the state the current market is in, my 'line wont be worth much thus rather keep it. I want to drift it someday as well, hehehehe. Care to join me on that venture...?

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