Strap - No strap.

[Soopy]

http://i157.photobucket.com/albums/t51/suprauc/nostrap.jpg


Guess which run showed the higher value...

I wonder how many workshops pull this wool over unsuspecting eyes?

[VYSHSV8]

Hell of alot......
I wonder if the best in OZ does this.... answer is yes I seen it in a video

[10sec_rx7]

maybe thats how people get claimed 310rwkw out of stock cam LS3... considering that dyno sheet is from a cammed LS3 if i heard correctly...

[Soopy]

Hell of alot......
I wonder if the best in OZ does this.... answer is yes I seen it in a video

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That video?

[FooSV8]

Loose strapped - higher reading

[VYSHSV8]

Yeh that's the Vid

[Soopy]

Loose strapped - higher reading

To the best of my knowledge, this is correct.

Just got me to thinking, how many workshops do this to sell product?

[FooSV8]

Most probably alot aye, its sad. Thats why i appreciate my tuner he showed the difference with full straped and loose strapped runs. so ya know theres no bullsh!t. although a dyno is merely a tuning tool but its cool to see some numbers :)

[Soopy]

Most probably alot aye, its sad. Thats why i appreciate my tuner he showed the difference with full straped and loose strapped runs. so ya know theres no bullsh!t. although a dyno is merely a tuning tool but its cool to see some numbers :)

That's exactly it. I agree, Dyno numbers are redundant - I just thought that picture might illustrate a few points that have been made on here recently.

[k1w1noz]

Yeh that's the Vid

OMG. That looks so sketchy without a strap. Don't think workplace health safety would be too stoked to see that. I'd be super pissed if I saw my ride get tested without a strap.

[Soopy]

OMG. That looks so sketchy without a strap. Don't think workplace health safety would be too stoked to see that. I'd be super pissed if I saw my ride get tested without a strap.

bqum1cNJGew

Its not unique...

[the big fist]

Personal favourite:

FAIL - EVO plummets and falls off dyno - YouTube (http://www.youtube.com/watch?v=oKFGr_mkQaA&feature=related)

[RB30X]

Can someone explain why the strap makes a difference to how the wheels spin the rollers?

[VYSHSV8]

Personal favourite:

FAIL - EVO plummets and falls off dyno - YouTube (http://www.youtube.com/watch?v=oKFGr_mkQaA&feature=related)

Haha Gold.......

[zorro]

Seen it plenty at dyno days, chocks on front and straps on just to beginning of tension. Gives everyone a good show and a half chub for the owners.....

[Soopy]

Can someone explain why the strap makes a difference to how the wheels spin the rollers?

I could be wrong, But I believe it has to do with the load distribution over the two rollers.
If you have two rollers both with X amount of force needed to rotate them, and you ride up on one, you'll get an inflated indication of effort.

Again, someone with more of an idea could clarify.

[dogsballs]

only a semi?! :(

[Soopy]

Seen it plenty at dyno days, chocks on front and straps on just to beginning of tension. Gives everyone a good show and a half chub for the owners.....

Makes no difference at dyno days. Little bit sus when you start selling it though.

[NIXON]

Can of worms soopy haha. What's the correct way to strap a car then? Tight, or just tensioned. I would have thought tight for safety concerns, but it appears you have a "happy dyno" if it's safely strapped???

[FooSV8]

Can someone explain why the strap makes a difference to how the wheels spin the rollers?

It has to do with the mathematics of the sofware in the dyno,
normaly full strapped run has both rollers in contact with the tyres,
loose strapped or no strap allow the car to ride up onto the front roller
which then reduces the force on the rear roller usually atleast 20Nm at ramp rate of 10kmh/sec which would make a 258rwkw pull, a 273rwkw.

(somewere on this forum a long while ago)

[XLR8 V8]

Most people that have been around dynos, or even just car forums, for more than 5mins know that strapping changes the figures. It's not some big secret that has just broken ACA style. The variation only matters if one run is done without strapping and the other with strapping. If they are both done the same way with a before and after tune dyno, then who cares, since the change is all that matters?? So many people obsessed with dyno figures ... yaWN.

[Delft Maloo]

Every single car that i have strapped onto my mates dyno and every single car that he puts on gets strapped regardless of its power level due to safety reasons, who gives a shit about power readings it is bloody stupid not strapping a car wether it has 100kw or 1000kw. All the cars we strap can done quite firmly but at this level you still have plenty of leverage onto the roller, the fronts wheels are chocked and on cars with suspected or known higher power levels we strap over the front wheels aswell to guarantee that there is no chance the car will leave the dyno.
Operators letting cars climb up or wonder on the rollers are just waiting for accidents to happen:teach:.

[FooSV8]

its not obsessed with dyno figures, its something which has passed my mind and probably alot of others, that some Shops tweek there dyno runs to pull a higher reading to sell products and its interesting to see what others have to say.

[JezzaB]

Can someone explain why when you have a high hp car you strap it tighter the wheels spin more?

[FooSV8]

Could be because when you strap a car down too tight it spoils the axle geometry and gives the rear wheels negative camber which would result in less traction

[Delft Maloo]

Can someone explain why when you have a high hp car you strap it tighter the wheels spin more?

i assume its a trick question as you'd know the answer but like most std strapping mounts/systems(on dd's, don't know regards mainlines) when you pull the car down harder it actually pulls the car backwards releasing pressure on the rollers allowing for easier slippage, if you have a decent strapping system that pulls the car onto the roller not away the problems aren't know where near as bad, from our experience.

[Wonky]

Similar but different - showing how strapping down tightly also robs power according to the dyno readout. Obviously not strapping at all or not to specifications adds to the reading too. http://www.ls1.com.au/forum/showthread.php?t=78700. All ways people can be fooled by dodgy shops. :(

[Martin_D]

Can someone explain why when you have a high hp car you strap it tighter the wheels spin more?

Bingo......

[godsvt2]

if you strap it on too tight the wheel will sit in front of the roller and slip which wont help your tune because your reading will be incorrect
:teach: if you loosen the strap off so the wheel sits on the top of the roller ie how the wheel touches the road when your driving you get the right reading
it doesnt give a higher hp reading than your making its the correct hp
this is why road tuning is so important less slip = better tune


but leave the strap on never have it unstrapped

[Soopy]

Bingo......

Bingo what?


if you strap it on too tight the wheel will sit in front of the roller and slip which wont help your tune because your reading will be incorrect
:teach: if you loosen the strap off so the wheel sits on the top of the roller ie how the wheel touches the road when your driving you get the right reading
it doesnt give a higher hp reading than your making its the correct hp
this is why road tuning is so important less slip = better tune


but leave the strap on never have it unstrapped

Hrmm.

[AGIT8D]

Similar but different - showing how strapping down tightly also robs power according to the dyno readout. Obviously not strapping at all or not to specifications adds to the reading too. http://www.ls1.com.au/forum/showthread.php?t=78700. All ways people can be fooled by dodgy shops. :(

I was going to ask that question re: over tightening being a power sap. The resistance would certainly increase, whether that aids anything I wasn't sure of. Will read thread now.

[Roonstain]

The funny thing is that you guys complaining about this and one sponsor, you have completely failed to realise (even though i have mentioned it!) that another sponsor here doesn't strap cars at all on their mainline - and yet no furore over that?

Double standards

[Toddler78]

I could be wrong, But I believe it has to do with the load distribution over the two rollers.
If you have two rollers both with X amount of force needed to rotate them, and you ride up on one, you'll get an inflated indication of effort.

Again, someone with more of an idea could clarify.


OH FFS Sopy the farken self apointed dyno police!:jerk: youve just admitted here that you have NFI so STFU
:sux:

[Soopy]

OH FFS Sopy the farken self apointed dyno police!:jerk: youve just admitted here that you have NFI so STFU
:sux:


What are you on about wanker?

[SVNLTR]

these threads are getting worst by the day

[Toddler78]

What are you on about wanker?

what Im on about is you are obviously bored, so you decide to start a thread on the merits of strapping or not straping a car on a dyno for the sole purpose of trying to stir up shit with OZTRACK or whoever your new target is, when you go on to say (in the post I originally referenced) that you have no idea what your talking about.

Im personally sick and tired of reading your tirades and personal vendettas on certain people/workshops nothing you post is of any relevance and what you do post is only limited to dyno related threads where you sit down from behind your keyboard in ya mums loungeroom critiquing professionals and criticizing them on everything they do