C7 Z06 FBO low torque opinions/insight
 

Hi all, I just had my m7 c7 z06 tuned after going fbo.

Wanting y’all’s thoughts/opinions/comparisons on my power numbers.

Tuned on 93oct
709whp/611wtq

I noticed my torque number seems low? Could lower torque # be result of tuner trying to keep things from being too aggressive or something? Any thoughts/insights on that?
I’m very happy with the WHP.

Mod list:
Cordes 5” intake
NWP 103mm TB
Kong “X” ported supercharger
2.3 upper pulley
DSX Lid
ARH Headers/catless x-pipe
Cordes billet heat exchanger
Cordes expansion tank
Brand new oem HPFP and related fuel lines

709whp/611wtq
I’ve seen similarly modded cars make 700+wtq
https://cimg0.ibsrv.net/gimg/www.cor...1eaf6f5469.png

When I bought the car it was previously tuned and already had 5”intake, headers, and 2.3 pulley and was supposedly making over 650wtq… so after adding x-port and 103mm tb, making less torque seems odd.

No fuel mods, you just replaced the HPFP with a new OEM one?

no fuel mods. Old HPFP was having issues, and wouldn’t supply more than 2000psi above 5k rpm. Replaced with new OEM HPFP, fixed said issue.

Mine wasn't really high either. I think it has to do with the 2" headers and ported blower...
https://cimg7.ibsrv.net/gimg/www.cor...a206598e84.jpg

What all mods do you have?
Ive seen other members with a mod almost identical to mine make 750+ wheel torque
Just seems oddly low compared to many others

Pretty much the same setup as you
ARH 2" headers
Big Gulp Intake
103 TB
X-Port with 2,38" pulley
Cordes HX and Expansion Tank
DSX Low side
DSX Flex Fuel kit
DSX Billet Lid
Running on E40

@Tfreud35 Could just be dyno variance, another shop may have much different numbers. Stock cars are making around 560-570wtq so I wouldn't put too much weight on those numbers being very accurate.

I was going to say this too. Unless you did a dyno measurement prior to the mods on the same machine it's hard to put much weight into dyno numbers after the fact. This is why I always have my guy do a base run before I start messing with my mods and tunes.
every machine is different and the uncontrollable variables (ambient temp, humidity, etc) don't help in consistency.

“INSIGHT NEEDED” FBO 93oct dyno numbers and torque
 

Hi everyone, just wanting some feedback on my dyno results based on my mods…
Is my torque low for my mods, or normal?

I feel like that torque number is really low for what’s done to the car.

Also, thoughts on my overall powerband(s)?

tuned on 93Mod list:
Cordes 5” intake
NWP 103mm TB
Kong “X” ported supercharger
2.3 upper pulley
DSX Lid
ARH Headers/catless x-pipe
Cordes billet heat exchanger
Cordes expansion tank

https://cimg7.ibsrv.net/gimg/www.cor...5e75fe5bab.png

Looks like all the right parts. That's also STD so will read higher than SAE numbers. I'm not an expert but I agree I'd think that should dyno a bit higher. The only major variable would be the tune and intake temps. Did you use one of the bigger, more well known tuners? Some dynos just read low also. 1/4 mile traps would also be helpful.

Not sure why you made a duplicate thread asking basically the same question, see the answers in your other thread from 2 days ago..

2 inch headers, 103TB and x port with a mild pulley setup slow down the velocity in lower RPM's and shift the powerband to the right. Low to mid range torque will be affected with the benefit of more high end HP. This is normal for these mods. Typically the X port is run with a more aggressive pulley setup to make up for the slower air velocity in the low/mid range. But if you're on street tires, having lower torque in the mid range is desirable and then once you're at WOT you're always above 5000 RPM where these mods shine, which makes the car faster.

The above statement is assuming a stock cammed LT4.

Might be a little low, adding in some meth would really help get more out of it. I have the same setup and made 775/680 spraying meth

Essentially duplicate threads merged.

I could see 2 causes. As mentioned above, the power band is shifted with these mods and not spinning the blower hard enough. There is also the potential that your tuner dialed back the torque down low in order to allow you to be able to get traction. Also, don't get caught up with dyno numbers. They are just a tool, and are not the best to measure different cars hp/tq against cars on different dynos. On the same exact dyno, sure, but just looking at any dyno that is found anywhere will lead to variances in almost all cases. There are so many factors that play into the number that you get, STD vs SAE and dynojet vs mustang and their respective calibrations. Just two possibilities, hope this helps

Also, the type of fuel matters. On 93 pump you have to be conservative on timing. With Meth or Ethanol blends you can be more aggressive at lower RPM's and pick up more toruqe.

Larger displacement blowers traditionally make a bit less power down low but more up top. Porting a blower increases its displacement at least a little bit. Honestly, I'd rather have peak torque around 600 than 700. Torque is what spins tires when you punch it from a slow roll; I'd rather have more up top and a bit less down low.

It increases the volume of the manifold but not the displacement of the blower. The blower "displacement" is determined by the rotor pack. By increasing the 1.7L blowers manifold volume, while not increasing its displacement, makes it less efficient at lower speeds. This is why adding a pulley when its ported makes up so much of the torque. You get the rotors spinning faster down low. If you spin an X port real hard (like 20-25% over) they hit real hard down low.

That said, since the X port makes significantly more power past 5000 RPM the car is usually faster at WOT because that is where it is operating. Even when you only do a mild pulley like a 2.3 upper.

Larger blowers make less torque if not spun in their efficiency range. But if you pulley them appropriately, they make a lot more torque than a smaller blower.

Dynos can vary so much, if you are concerned with power levels I would get some 1/4 mile trap speeds logged.