Thurr

Went to a dyno pull today and had my S4 dynoed along with another almost identical S4 (2000, ABox, APR Stage 3 running 104 program using the same fuel). The only differences are I have larger IC's (RS4), ASP downpipes (he has piggies), UUC VM3 exhaust (he has Borla) and I have a bi-pipe. Neither car has had any tweaking - we're running the same program.

I dynoed right after him. He got 374/394 and I got 351/409.

Any suggestions about why my HP isn't higher and why the wide gap between HP and torque? Another S4 (Stage 3?) did 360/388.

It seems as though I should be around 385 or so. What are some of the things I should check that might be affecting my HP numbers? Thanks.

FTW

Yeah, something is wrong. You should be over 400 first of all.

The_Jerbel (Jordan)

You are running out of steam up top, try logging your MAF values and ign timing.

Wrinkledpants

but doubtful

The_Jerbel (Jordan)

It just depends where in the power band you are making the torque.

Thurr

Max Torque: 409 @ 3250, Max HP: 351 @ 6250

Wrinkledpants

Right, I wasn't insinuating that 351/409 was taken at the same RPM.

WECoyote-SuperGenius

My ots apr Stage 3 numbers on a Mustang Dyno:

93 oct. (whp/torque)
362/377, wcf: 351/366

100 oct.
382/431, wcf: 365/411

DocSlowMiniPerson

Boost profile that spikes quick and tapers hard could easily explain it.

Thurr

At 3250 torque 409 and tapers to about 290 at 6250. HP at 3250 is about 260 and rises to 351 at 6250. Neither curve has much of a spike.