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-   -   Fast Intentions exhaust and header comparison. Before and after UPRev tune (Dyno) (http://www.the370z.com/intake-exhaust/16039-fast-intentions-exhaust-header-comparison-before-after-uprev-tune-dyno.html)

XwChriswX 04-09-2010 12:00 PM

What can we do to help bring it back to vertical?

semtex 04-09-2010 12:06 PM

Quote:

Originally Posted by XwChriswX (Post 488313)
What can we do to help bring it back to vertical?

You don't want it vertical, lol. You want it horizontal. (Maybe that's what you meant.) But seriously, I'm wondering if it has something to do with the AT. I mean, considering how flat mine looks (which is 6MT).

http://www.the370z.com/members/semte...n-04-07-10.jpg

XwChriswX 04-09-2010 12:08 PM

Quote:

Originally Posted by semtex (Post 488322)
You don't want it vertical, lol. You want it horizontal. (Maybe that's what you meant.) But seriously, I'm wondering if it has something to do with the AT. I mean, considering how flat mine looks (which is 6MT).

http://www.the370z.com/members/semte...n-04-07-10.jpg

You don't want it going up? I thought more = better? Or is that just for HP?

semtex 04-09-2010 12:12 PM

You want it to go up as early as possible to its peak level, then stay there. What that translates into is a car that pulls early and continues to pull all the way to redline. If you had a curve that went upwards, it would mean that the car only pulls as the revs get high (think Honda VTEC). And I don't think you'd want that with this car as people already complain about how there's a lack of grunt below 3k rpm.

semtex 04-09-2010 12:18 PM

I found wstar's dyno sheet (also 7AT). It's flat for his 7AT as well.

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

XwChriswX 04-09-2010 12:18 PM

Quote:

Originally Posted by semtex (Post 488332)
You want it to go up as early as possible to its peak level, then stay there. What that translates into is a car that pulls early and continues to pull all the way to redline. If you had a curve that went upwards, it would mean that the car only pulls as the revs get high (think Honda VTEC). And I don't think you'd want that with this car as people already complain about how there's a lack of grunt below 3k rpm.

OH ok. I thought you wanted it to 'keep' pulling, so going up on the scale. See like I said, I'm pretty low on knowlege of the science of dynos lol I just know higher numbers = good (minus practicality)

semtex 04-09-2010 12:28 PM

Quote:

Originally Posted by XwChriswX (Post 488345)
OH ok. I thought you wanted it to 'keep' pulling, so going up on the scale. See like I said, I'm pretty low on knowlege of the science of dynos lol I just know higher numbers = good (minus practicality)

Right. A flat torque curve means that it keeps pulling. A torque curve that goes up means that as rpms build, it pulls at a higher rate. You'd see that with many turbo apps -- as the turbo spools up, the torque increases, but prior to the spool-up there's not much torque (aka turbo lag). Now, what concerns me about Pablo's curve is that, based on how the curve drops off at 5k, it means that as his rpms climb from 5-7.5k, his car is actually decreasing its rate of pull.

XwChriswX 04-09-2010 12:30 PM

Quote:

Originally Posted by semtex (Post 488362)
Right. A flat torque curve means that it keeps pulling. A torque curve that goes up means that as rpms build, it pulls at a higher rate. You'd see that with many turbo apps -- as the turbo spools up, the torque increases, but prior to the spool-up there's not much torque (aka turbo lag). Now, what concerns me about Pablo's curve is that, based on how the curve drops off at 5k, it means that as his rpms climb from 5-7.5k, his car is actually decreasing its rate of pull.

Is that a 7AT problem? Or something specific to his runs? I hope all 7ATs arent like that... That would piss me off. lol

You Smoke a CRX to see him putt putt putt past you just before the 1/4 mile lol

semtex 04-09-2010 12:42 PM

Quote:

Originally Posted by XwChriswX (Post 488366)
Is that a 7AT problem? Or something specific to his runs? I hope all 7ATs arent like that... That would piss me off. lol

You Smoke a CRX to see him putt putt putt past you just before the 1/4 mile lol

Well that's why I posted wstar's dyno sheet a couple of posts above. Did you miss that? lol

XwChriswX 04-09-2010 12:44 PM

Quote:

Originally Posted by semtex (Post 488398)
Well that's why I posted wstar's dyno sheet a couple of posts above. Did you miss that? lol

I saw it, but i didnt remember it until after I posted mine.. and I'm too lazy right now to ninja edit... Need to eat, strength waining... :icon14:

Pablo Z 04-09-2010 01:59 PM

1 Attachment(s)
Quote:

Originally Posted by semtex (Post 488292)
Wow, I'm surprised to see how the TQ plummets after 5k rpm.

Quote:

Originally Posted by vipor (Post 488310)
yeah most TQ "curves" on the VQ's are pretty flat....

I had the same question and the tuner came back to me today and pointed out that the scales are different between TQ and HP - duh
He sent me a dynojet format and it looks like what you would expect

vipor 04-09-2010 02:01 PM

That's still a LOT of fall off after the 5250 (crossover on a NA) mark.

Did the A/F go back up to 13 at that point or something?

semtex 04-09-2010 02:16 PM

Quote:

Originally Posted by vipor (Post 488555)
That's still a LOT of fall off after the 5250 (crossover on a NA) mark.

Did the A/F go back up to 13 at that point or something?

Actually, I think it looks right. It just looks a little exaggerated due to the scale. The y-axis is in 10 lb-ft increments, so even relatively minor changes will look a little bigger. Also, compare his graph with wstar's. Notice that the y-axis on wstar's graph is in increments of 40 lb-ft. And also notice that both curves end at 200 lb-ft @ 7500 rpm. In fact, if you look at 5k rpm, Pablo is making more tq (probably due to his tune).

http://www.the370z.com/attachments/i...ojet-style.jpg

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

vipor 04-09-2010 02:54 PM

per 500rpm from 5000 the first drops 5, 10, 5, 15, 15 - (35ft/lbs by 7000, 50 by 7500)

per 500rpm from 5000 the second drops <5, ~5, ~0, ~5, ~25 - (<15ft/lbs by 7000, ~40 by 7500)

"~" means "approximately" by the by

semtex 04-09-2010 03:00 PM

I know what ~ means! (And it's called a tilde.) :p Yeah I'm not saying they're identical. Pablo's curve still isn't as flat as I'd expect it. I'm just saying it's not as bad as it might initially look is all.


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