[Harry]

Havent seen a Before and After shown before - so put up for interest

Before:
UK Spec R33
unmodified but for boost at 1bar

After:
as Before, but add
Apexi Induction Kit
De-kat pipe
Trust Downpipe
Dual Drager exhaust

Data is off Abbey's Dynapack - so at axle
I thought the most interesting part was the change in the shape of the torque curve....(of course the overall improvement is also satisfying )

cheers

Harry

 

[Peter]

Nice improvement Harry, very noticeable on the road no doubt! Something tells me you're not making over 1000ft/lbs of torque though, what's that all about?

Peter.

 

[Lee_Pendlebury]

I would like this answer too for my graph. I assumed you divide it by 4 seeing as 4 wheels are driven but realyl have no idea.

Cheers
Lee

 

[[email protected] M/S]

torque figures

PE,

the dyno reads the torque at the axle so the figure is multiplied
by the axle ratio[ gearbox and diffs are torque multipliers]
So divided the axle torque by the diff ratio as we run the car in 4th gear 1-00 gear ratio you get the flywheel torque.



Mark

 

[Peter]

Cheers MG.

So what's David's peak torque, 270 ft/lbs?

PE.

 

[Harry]

Peter

ratio is 4.11 I believe

giving torque of:

before peak is 263ft/lb at 4500

after peak is 274ft/lb at 4200

Mark - trust I got this right

cheers

 

[jae]

Dip

Is it my misinterpretation, or is there a power drop off around the 2600-2800 rev range on the pre stage 1 graph?

 

[Harry]

Jae - re power - you're right (you can see it in the torque curve)

I dont know why though?

 

[Peter]

Harry,

I would guess it's as the wastegate starts opening, looks like you've now got better boost control to me although your torque still dips a bit at about 5k. May be think about a boost controller next....

Peter.

 

[Harry]

Thanks Peter - the shopping list gets longer all the time....

re the dip - have also seen other flatter curves from a remap...damn...add a programable ECU to the list also

 

[Peter]

The modifying bug has got a few teeth into you already Harry, just wait until it bites hard!!

 

[slippyr4]

Is that really just over 280 horses at the wheels from standard+1bar ??? that seems a lot to me?!?!

 

[Peter]

At the hubs, not wheels so transmission losses will be less than at the wheels. Stacks up to me.

 

[slippyr4]

why would there be a significant difference in power at the wheels and power at the hubs? they're connected with 5 big studs!!!!

 

[Peter]

Errr, tyres. I'm sure Abbey would have an idea how much rolling resistance these will give you. My guess is that it will be relatively significant though....

 

[Peter]

Regardless of that, most stage 1 cars make anywhere from 370 to, in one case (SteveC), 415bhp. Normal transmission losses on chassis dynos seems to come out between 120 and 135bhp. So add to 280 a slightly lesser tranmssion loss of say 100bhp, you're back to the norm, 380bhp. As I said, it stacks up to me.

 

[slippyr4]

and what do you define as stage 1 ? air filters, exhaust, decat and 1bar boost ? anything else?

 

[Peter]

Not sure where this is going or what you're getting at....?

 

[slippyr4]

Just asking you a question, thats all! you say that stage one normally makes 380 ish, and i just want to be clear on what that stage one involves. a lot of people regard different things as stage one.

 

[Peter]

OK then. A fairly typical stage 1 car would be like Harry's, have a look at the first post in this thread. SteveC's car made 415bhp with more or less the same spec list.