I know DaveW has one,anyone else have these fitted to their Z?Did you notice a differance after it was fitted?

Thinking of having one sent up from SE next week.

Ditto Dave- very noticeable, especially 'low-down'

Dave

Originally posted by WillieO

Beware add-on devices with dubious power claims.

 

Ask yourself why do they make em in different pretty anodised colours? answer because a marketing person is selling them not an engineer!

 

the 2 or so extra bhp only come at high revs - just when harmonic vibrations might be wanting to tear your crankshaft to bits. Nissan didnt put the weights on the stock pulley for nothing.

It damps harmonic vibrations at certain frequencies and makes the motor smoother.

 

The reason they annodise them is to harden the material due to using soft aluminium which could get badly worn by the belts ;)

Dave

 

The dyno chart shows a whopping 11bhp increase overall in max bhp. And these are SAE bhp which I think are not as big as DIN BHP.

 

Max effect around 4200rpm. Why only there? if the savings should be accross the rpm range? Maybe thats where the stock pulley is doing max damping of vibration frequencies excited in the crankshaft so you save there but get vibration instead.

 

Hardly anything before 3000rpm - so the dyno doesnt notice any low down effect whatsoever??

 

I dont believe I could feel 11bhp difference personally maybe 50 tho.

 

even a curious loss of power about 2300rpm - new vibration frequency excited in crankshaft due to new pulley?

 

Then there is always the possibility the dyno has been "influenced" to maximise the gains to justify the mod.

 

stimulating some debate here!!

 

Willie

How about this one then?

 

http://www.ttzd.com/rides/dynocharts/dynochart31.jpg

 

There's still "only" an increase of 12bhp, but it's a fairly obvious increase throughout the rev range.

 

I suspect the first one involved a gear change, which would account for the odd peaks/troughs low down.

 

If you can't feel a 12RWHP difference, I wouldn't bother with doing the exhaust, intake, decat, etc, etc. :p

LOL Mac banging head off wall:D:rolleyes:

Originally posted by Dave Marley

I suspect the first one involved a gear change, which would account for the odd peaks/troughs low down.

 

Maybe I misunderstand what you mean but when doing a dyno run there are no gear changes involved. The gear which is closest to 1:1 overall ratio is used and only that gear.

 

CheerZ,

 

Andy

Originally posted by andyduff

Maybe I misunderstand what you mean but when doing a dyno run there are no gear changes involved. The gear which is closest to 1:1 overall ratio is used and only that gear.

I know there's not supposed to be a gear change.

 

Can you think of any other reason for the troughs around 2300rpm?

Probably something to do with the turbos sapping power but not actually generating any back. As the exhaust flow increases, the turbo impellor presents more restriction, as the turbo gains speed, you start to get your gains back again but up to a certain speed all the turbo does is restrict the exhaust (and also the intake to a certain extent). So basically IMO that is where the turbos are 'choking' the engine.

 

Any other ideas?

 

Have I made any sense at all? :D

 

CheerZ,

 

Andy

Dave

 

Its partly my point - there you have 2 dyno tests with different results for basically the same mod on the same engine - hardly repeatable objective evidence m'lud. Do you pick the one you want to believe?

 

If you can't feel a 12RWHP difference, I wouldn't bother with doing the exhaust, intake, decat, etc, etc

 

I think i'd struggle to feel 12bhp on a megane let alone a 1.6 tonne zed.

 

Mine has exhaust done with pipes a small dog could get up before I bought it so I cannot compare before but I did do the intake kit instead of K&N panel filters and it sounded different at full whack (noisier) and I think it feels faster but I could be deluding myself into believing I just won 15bhp!

Originally posted by WillieO

Its partly my point - there you have 2 dyno tests with different results for basically the same mod on the same engine - hardly repeatable objective evidence m'lud. Do you pick the one you want to believe?

One was on a stage 3 and one was on a stage 5 car. They both showed around an 11-12 increase in peak rwhp. Seems fairly decent evidence to me! :D

 

I did do the intake kit instead of K&N panel filters and it sounded different at full whack (noisier) and I think it feels faster but I could be deluding myself into believing I just won 15bhp!

On the other hand, you could accept that your feelings were correct (and just happen to agree with all the dynos people have done when they added a cone filter!). :rolleyes:

 

I don't see that you can really argue that there's no power difference when you've seen 2 dyno charts showing a power increase, and both Dave and myself have had them fitted and felt an obvious difference, unless you've done it yourself and felt nothing. :mad:

 

:D

Originally posted by Dave Marley

......unless you've done it yourself and felt nothing....

 

Depends if you sit on your hand first :D:D:D:D:D

If 2 identicle Z's race side by side on a straight stretch the one with a 12 hp advantage will pull away from the other FACT

whether you think you can feel it or not.

Tuning is about gaining a little here and a little there it all adds up

I'm glad its Friday!

 

If 2 identicle Z's race side by side on a straight stretch the one with a 12 hp advantage will pull away from the other FACT

 

Similarly

 

If the one with the 12bhp advantage turns up his 2000W hifi with some heavy metal at the time the 3bhp electrical demand will consume 12bhp at the flywheel and the advantage is gone and thats before the extra weight of the amps and subs is included.

 

Also if you've loads of bodykit and a lard ar5e mate inside advantage gone. In fact just a neat slim other=advantage gone.

 

I accept that there is a gain in bhp just that it aint so much to get excited about and is it worth the cost/risk?

Originally posted by paulg

If 2 identicle Z's race side by side on a straight stretch the one with a 12 hp advantage will pull away from the other FACT

whether you think you can feel it or not.

Tuning is about gaining a little here and a little there it all adds up

 

FFS this thread has gone out of control.

 

 

Ok What about this...................................................

 

 

 

 

 

I am sat in my Z I weigh 18st4 lbs

 

Duffer his sat in Stuarts Z he weighs 2 stone

 

 

 

 

Who would win the race?:confused: :confused: :confused:

Originally posted by WillieO

Also if you've loads of bodykit and a lard ar5e mate inside advantage gone.

 

OK Macca, I see why you don't want one now! :D

Thats one bodykitted car I really like!

Originally posted by ChrisC

OK Macca, I see why you don't want one now! :D

 

Cheeky git!

Originally posted by WillieO

I'm glad its Friday!

 

 

 

Similarly

 

If the one with the 12bhp advantage turns up his 2000W hifi with some heavy metal at the time the 3bhp electrical demand will consume 12bhp at the flywheel and the advantage is gone and thats before the extra weight of the amps and subs is included.

 

Also if you've loads of bodykit and a lard ar5e mate inside advantage gone. In fact just a neat slim other=advantage gone.

 

I accept that there is a gain in bhp just that it aint so much to get excited about and is it worth the cost/risk?

 

what a stupid argument :rolleyes: if he didnt have a 12bhp advantage then he would be even more disadvantaged in the above scenarios!!

 

as mentioned previously, its all the smaller mods that add up. if your not into tuning then leave it stock. if you are then any bhp increase is worthwhile