My dyno sheet from yesterdays upgrades..

Sneaky Peaky

Sneaky Peaky

Sneaky Peaky

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Here's my dyno sheet from the upgrades I had done yesterday at Powerstation in Tewkesbury. I'm afraid I have no clue about these things so if you guys could give some pointers on what looks good/bad that would be great.
It's a MY06 Subaru Forester 2.5 FXT - engine mods are 3" Milltek turbo back system, VF39 Turbo, 255lph Walbro Fuel Pump and Tek3 remap. Unfortunately I couldn't get the upgraded intercooler on so had to stick with the oem one but plan to upgrade asap.

Cheers
Pete

6aaef8b4.jpg
 
Interesting - not as much as a jump as I'd of thought. Will be interesting to see what difference the intercooler makes.

Still flippin' fast no doubt :D

Fancy a race? I reckon it'd be close ;) :p
 
Will be a lot of transmission loss - Subaru 4WD powertrains are quite 'lossy' from what I've seen.

Thats 211 at the wheels - isn't it normally compared at the crank in the Uk ? ie 313bhp normalised..
Click to expand...

Not sure what you mean by that? :)
 
Sneaky Peaky said:
Thats 211 at the wheels - isn't it normally compared at the crank in the Uk ? ie 313bhp normalised..
Click to expand...

But then different dynos 'calculate' different crank figures...

Nevermind the fact that wheel dynos are only good for setting up and have far too many variables to provide comparison power figures.

also is it 310 lb-ft torque according to this link..

http://www.boltscience.com/pages/convert.htm
Click to expand...
That'll teach me for counting on my fingers...

I'm interested in what you guys think of the curves etc..
Click to expand...

It looks a bit slow to get going - although not as bad as nothingnothingnothing300lb/ft.

*n
 
Sneaky Peaky said:
Thats 211 at the wheels - isn't it normally compared at the crank in the Uk ? ie 313bhp normalised..
Click to expand...

You can only compare 'at the crank' if you run it on an engine dyno.

*n
 
Max power was measured at 317bhp at the engine. Isn't that what people quote as max power when comparing as opposed to the figure at the wheels.
I think the normalised figure takes into account the conditions on the day or something ?

ie based on this chart my max power would be 317bhp and 310 lb-ft torque..
 
Sneaky Peaky said:
Max power was measured at 317bhp at the engine. Isn't that what people quote as max power when comparing as opposed to the figure at the wheels.
I think the normalised figure takes into account the conditions on the day or something ?

ie based on this chart my max power would be 317bhp and 310 lb-ft torque..
Click to expand...

Yes, but power at the crank as measured on a rolling road through the wheels is essentially a calculated estimate. Many different factors could vary this figure by significant amounts from the actual figure.
 
Sneaky Peaky said:
Max power was measured at 317bhp at the engine. Isn't that what people quote as max power when comparing as opposed to the figure at the wheels.
I think the normalised figure takes into account the conditions on the day or something ?

ie based on this chart my max power would be 317bhp and 310 lb-ft torque..
Click to expand...

As Scuzi said and I alluded to earlier; different rolling roads have different means by which they 'calculate' a flywheel bhp figure. The only way you can get a true flywheel power figure is by removing your engine and placing it on an engine dyno.

Your maximum power is 211bhp at the wheels. Calculated flywheel figures mean bugger all.

Tyre pressure, tyre construction, tyre compound, diff oil, temperature, humidity and many more variables all have an effect on transmission losses so it is meaningless to use them for comparison purposes.

*n
 
Yep - ok I understand that now, many thanks..

My point is though when generally people say , my car does 400 bhp blah blah they are talking about the estimated engine figure from a rolling road, not the at the wheels ?
 
Sneaky Peaky said:
Yep - ok I understand that now, many thanks..

My point is though when generally people say , my car does 400 bhp blah blah they are talking about the estimated engine figure from a rolling road, not the at the wheels ?
Click to expand...

Yeah, it's all pub talk though :p
What really matters is real world performance. I wouldn't worry about a number, if your car performs how you want it to that's all that matters. That's in my opinion but some people see bigger BHP figures as a penis extension.
 
Ahem

No chassis dyno MEASURES BHP at the wheels...

Its all calculated from the torque figure and the rpm....

The torque figure is the one you should be interested in, then you can calculate your own BHP from the formula


Hp = (rpm x torque)/5,252

So go do the math yourself...


Penski, can you supply us with details of a Dyno that measures engine BHP please...

And you dont need an engine dyno to get accurate figures if you have ACTUAL measured losses for a particular transmission however, most actually dont, and also most dynos are massively out of calibration, so the only purpose they serve is to compare pre and post mod vehicles, or compare vehicles on the same day...

So come on you dyno "experts" stop giving out all the BS and making out you know

:p

PS a stock 2.5 forrie turbo will hit 60 in 5.6 seconds, so now modified its gonna be a lot quicker... and thirstier...
 
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