I would consider an intake an exhaust, even if the exhaust is custom made with extra mufflers to keep it quiet. With the other breathing mods you have they will help.

 

Well I'm pretty shocked because HRP is a very quick track, even in the heat. It's basically at sea level and I've found through my own personel experience with my old 94 Z28 that HRP is about .3 and 2mph faster than my strip here in Kansas City.

Density altitude (DA) conditions for the day you race were 1,700'. Not great, but far from bad. I'm not trying to make you worried, but has your car been running right lately? The reason I ask is I've run in 1,800' DA and did 14.6s@97.7mph stock launching off of idle (2.3 60 foot) and that was the car's maiden run. I then upped the launch rpm and did 14.49@97.7mph with a 2.1 60 foot on the next run. With the spacer, I've done high 14.3s@99mph+, but I did have a 10mph tailwind which would improve trapspeed. I would think at HRP and in those conditions, you'd be seeing at least 14.4s@98mph, if not quicker.

Maybe it's a fluke thing. Next you go there, do the following:

1) Don't burnout. It's not necessary at all with street tires.
2) Turn off the VDC.
3) Take out all excess weight (crap in the trunk, spare). Race with a 1/4 tank of fuel and make sure it's premium.
4) Stage the car and once staged, put foot on the brake and rest your foot on the gas.
5) When the tree starts to drop, plant the gas to the floor and release the brake on the last amber. You should come off the line at around 2500rpms.
6) Let the car shift the 1-2 itself and then manually shift the 2-3 at an indicated 6400rpms.
7) Hold 3rd gear the entire run. DO NOT let it shift into 4th because it will kill ET and MPH by a couple tenths and around 2mph.

 

With VDC on, it shouldn't be surprising. It cuts the power, so you aren't really putting down everything your car is making. Hence the low HP calculation and slow time.

 

What? Do you drive the same car I do?

My car dyno'd 241/210 stock. After a stillen airbox, motordyne 5/16 spacer, mrev+ lower plenum, ichiba headers, kinetic resonated test pipes, stillen exhaust, utec with a tune, ngk iridium spark plugs, jtw flywheel, and a custom oil catch can, I dyno'd 265/250.

"alot more than 30hp" - that's funny.

 

Ill grab the dyno sheets from work today of the N/A G35's we've tuned.
Also, this guy is just making passes on the dyno with no TUNE or Reflash. I stated that he could get more power if he purchase a UTec. If he gained 30hp without a tune, then he could gain more with a standalone/piggyback.

 

What's odd is his car isn't accelerating like one with 240whp/220wtq. I'm assuming he did all his runs at the same shop, but I'm still very confused as to why his car isn't running like it should.

 

How can you be confused? HE HAD VDC ON!
Hell, on top of that, he could be running bald all-season tires for all we know.

 

He also brake torqued – which I’ve been saying for yrs bogs you down off the line because the ECU cuts power briefly… I’ve done boatloads of various launches and on my car my 60’ and ET are better launching off idle… you can literally feel the car bog off the line when throttle and brake have been applied at the same time – it just kills 60’ times. It takes a moment before the car actually gets up and goes. It’s like how a horse stutters in the gate before hauling @ss down the track.

Anyway – that’s why I suggested to him to do back o back runs – one with brake torque to 2K or 2500 and the other off idle and see how his time vary.

 

Running with the VDC on WILL NOT slow your car down unless you've got wheelspin. At my strip, my car will barely chirp a tire. I've run with and without the VDC on and there's no difference in ET/MPH. He didn't report excessive spinning therefore I assumed he wasn't getting any.

 

My experience is a bit different from yours. I've launced off idle and then with brake torquing. My 60 foots are at least .15 seconds quicker on average with brake torquing (high 2.1 vs low 2.3 60 foots). I do agree, the car does bog down a bit on launch, but's it's even more noticable launching off idle. When I brake torque, I'm only holding the brake and gas down together for about 1 second. If I hold it longer, the car is really boggy coming off the line. Next time I go to the strip, I going to disconnect the yaw sensor which allows my car to do a standing burnout and it appears to remove some of the nanny that does like it when you apply the brakes and gas at the same time.

 

VDC kicks in before I even get wheelspin. In my Z, VDC made a ridiculous difference in straight line performance. I didn't get excessive wheelspin, either, but the system prevented full acceleration regardless.

In my X at the autoX, turning off VDC made a 3-sec difference. Yet it was so inconspicuous in its intrusion that I didn't even realize I had left it on for 3 runs. Car still ran well with it on, but it ran BETTER with it off.

And, like I said, we don't know about his tires. So while yours may hook up well and not invoke VDC, we don't know that about the poster's tires.

 

Yes, there's more there. But not a lot more. A tune gave me an average of ~7.5hp and 8.83tq. His gains may be more, may be less; it's gonna depend on how well the ecu is self-tuned as it is. I'm guessing its adjusted rather well to see a ~30hp increase, so I doubt a tune is going to give much more.

Yes, it's more. But not a lot more.

If you wanna see the details and my analysis, here's my original thread:
https://g35driver.com/forums/reviews/143552-final-numbers-revup-bolt-ons-utec.html

 

Interesting point regarding time spent with brake and throttle... I never really considered it would be different by only allowing a short duration. I'll give it a try next time.

I'm still hopeful of a full ECU defeat so it doesn’t even recognize both are applied and doesn’t do anything about it... I'm not sure anything like that will make it to production because of risk/liability concerns - but I'm going to re-visit it with a couple of people that might be able to help.

 

Did you ever read this thread? https://g35driver.com/forums/drivetrain/161288-burnout-switch-mod.html

Also, here's something from KPierson that might be of interest, though I haven't read the thread:
http://my350z.com/forum/forced-induc...installed.html

Also, I know he was working on a module for brake boosting a while ago, and the last time I checked, he was having problems with the module and 5AT's. However, you might want to contact him to confirm. Here's the post:
http://my350z.com/forum/forced-induc...ml#post4500825

Hope that helps man.

 

thanks Trey - yeah, I'm familiar with all those threads... and Kevin @ KP wasn’t able to get the mod to work for ATs... I've spoken with him about it and through posts... He did my taillight module - I may re-visit the idea with him to see if he is willing to take another stab at it... the others (threads) don’t address exactly what I'm referring to unfortunately.