Well, the throttle inputs might not be the same between the runs. I think on my next DD run, I'm going to ask the guy to make sure he drops back under 3K before he floor the throttle and takes the run. It's not a very well-controlled variable, and since most people are just looking for the peak HP number anyways, it doesn't matter to many. It would be nice to hook up OBD-II to the dyno machine and get throttle position mapped onto the graph as well if that were possible.

That's what I've noticed as well, mostly in the form of the car having less "jerk" at low rpms (esp at 3k-ish and below). Looking at my graph here:

http://www.the370z.com/members/wstar...-tq-vs-rpm.jpg

The low torque before hitting the peak at 4250 can either be low-rpm torque loss from headers, or it again could be throttle input issues near the start of the run, I'm not really sure. I'm pretty sure everything before 3500 is from lack of WOT though.


I actually like the sound of my full setup most of the time. The only thing that still bugs me (and that the headers undoubtedly exacerbate) is the extreme rasp around the 2500-3000 range even at light throttle. I wish I knew how to fix that with some kind of rubber damper (like the two that are already on there from the stock setup).

Hmm...I don't detect any rasp. I wonder if the fact that I had my headers wrapped is making the difference.

Could be.

Can u make a video of how it sounds from the outside!

You know what, guys? The loss of low-end torque isn't really as bad as it looks on that graph. Keep in mind that the units on that graph are in Newton Meters (Nm). The gap wouldn't look that bad if it were in ft-lbs. (Sharif said he had an issue with the last firmware upgrade from DD in Australia.)

I think I'm going to do that tonight. I was planning to recheck my header<->cat bolts and front O2s for any new looseness this evening anyways, and get started on some of my misc projects (like washer fluid delete, maybe the TB coolant delete too). After I'm done with that, late tonight when there's not much traffic around, I think I'll find an isolated road where I can leave the camera on the ground and make a few passes at various speeds/rpms/throttles.

hmm what bothers me is that I like the torque. I like that jerk when I punch it in the power band. Are you saying that is gone?

It's not gone in the power band, we're just debating whether it's gone in the low end.

No, it's still there. It's just a little . . . 'softened' at lower rpms. It's too bad we don't live in the same city, otherwise I'd just let you drive it.

Btw, I'm about to post a video of the dyno.

Move down here. 305 > ATL

on a more serious note.... I e-mailed Josh about what I was thinking, waiting for a reply.

Oh and good that it isn't gone.

If the gains I can expect from having a full STILLEN setup are the ones advertised on their site. (14.5whp and 10+tq) then I will install... may have to look into wrapping them too. Keeping heat in the headers makes the turbo spool faster!.....err...I switched cars...no longer applies...though it may help with flow.

Hmm...I'm not sure how they're getting 10+ tq. Well, maybe if the rest of the exhaust is stock? I think that's what RelentlessRY did right? And he said he made tq on the top end but lost a bunch in the mid-range?

Alright, here's the video. (I'd better get some rep pts, tvfreakazoid! ;) I wasn't going to bother doing this until you asked.)

Thanks for the external vids, Semtex! That second graph was about as linear as it gets for whp. Even though the headers aren't quite where you wanted them, what is your impression of your setup as it stands?

S.

Awesome man. Nice results on Sharif's dyno :D

Chris

Thanks for the info. Semtex.