If our cars pick up 8 wheel hp how much is that at the crank?

[pr086]

Topic

[YourFearlessLeader]

10

[Xdragonxb0i]

We lost about 20% give or take

[so26]

looks like drivetrain losses are ~17.5% on the twins (manual trans).

Therefore,

CHP = WHP/(1-0.175)

so a 8 whp gain is 9.69hp gain at the crank.

[tech4pdx]

Originally Posted by Xdragonxb0i

We lost about 20% give or take

That's what I've seen more often than not. Depends on the dyno. Possibly quality of fuel..

[whtchocla7e]

How did you pick up these extra 8whp?

I would like a 8whp on the cheap.

[pr086]

Originally Posted by whtchocla7e

How did you pick up these extra 8whp?

I would like a 8whp on the cheap.

i bought a chip off ebay...

jk. that seems to be about what you can expect from a drop in filter and catback

[DarkSunrise]

Originally Posted by so26

looks like drivetrain losses are ~17.5% on the twins (manual trans).

Therefore,

CHP = WHP/(1-0.175)

so a 8 whp gain is 9.69hp gain at the crank.

I suspect our engines don't make the full 200 hp until somewhere after 5000 miles (i.e., fully broken in). DD Performance demonstrated that their stock FR-S dyno'd at:

- 166 whp with 250 miles
- 171 whp with 2500 miles
- 174 whp with 8500 miles

on their dynojet. Based on that, I'd guess the drivetrain loss on the twins is a bit lower, probably 13-15%.

http://www.ft86club.com/forums/showt...?t=7319&page=3

[KGFRS86]

Originally Posted by DarkSunrise

I suspect our engines don't make the full 200 hp until somewhere after 5000 miles (i.e., fully broken in). DD Performance demonstrated that their stock FR-S dyno'd at:

- 166 whp with 250 miles
- 171 whp with 2500 miles
- 174 whp with 8500 miles

on their dynojet. Based on that, I'd guess the drivetrain loss on the twins is a bit lower, probably 13-15%.

http://www.ft86club.com/forums/showt...?t=7319&page=3

I just hit 5k the other day...not sure I noticed any difference but about a thousand miles ago I'd say it's picked up a little bit. Has anyone else seen this and can confirm it or just those guys?

[DarkSunrise]

Originally Posted by KyleGato

I just hit 5k the other day...not sure I noticed any difference but about a thousand miles ago I'd say it's picked up a little bit. Has anyone else seen this and can confirm it or just those guys?

I think it'd be hard to find more of these kinds of dynos. I don't know of anyone else dynoing their cars stock every few thousand miles.

It is pretty common knowledge that most cars gain some hp after the break-in period (you see it sometimes when magazines do 0-60/quarter mile tests at the beginning and end of long-term tests).

[muffinman]

Why would u need to know that? "At the crank" hp would always be an estimate unless u took the motor out. Dyno it, get baseline whp, then stick on the bolt on and dyno it on the same exact dyno in similar temperature.