+1

Mine is the same way...

 

Ditto.

Knowing your car power curve and its transmission gearing you can optimize your shift points for your car. If someone can provide me with some tabulated dyno data I will illustrate. Also, a single shift point is not ideal either, as some gears are spaced wider than others. Utlimate the name of the game is to maximize the average power for your run. This is achieved with the gear exit power equal the next gear entrance power.

Basically what I do is find out gear ratios and final drive ratio. Tabulate power and engine speed. Then I will generally curve fit the dyno data with a 4th degree polynomial equation. With the power curve equasion, I can then simulate a run through all the transmission gears and plot it the engine output to optimize shift points for each gear.

 

^let me know if u need any kind of data.

 

Shoot me some stock rev-up data and some stock non-rev data, or closest thing to it. Tabulated format. some dyno software output tables, print-out/scan will do also.

 

1) It's not just all about peak power. Like Klubbheads stated, you might not get that much in peak power. With test pipes, exhaust, plenum spacer, MREV, & a flash, you might get 15 peak hp/tq out of it. But as much as 30 hp/tq under the mid-range curve.

2) You cannot add manufacture claims to each other, expecting it to add up. In the automotive world (regarding power of modifications), 2+2 does not equal 4

3) Alot of manufactures over inflate their numbers. They seem more like flywheel power gains rather than their "whp" gains.

4) A little research will help you understand how the VQ works alot more

.

 

Maybe with a tune.

 

The tuning section on this site has some really interesting data that you might want to read. I've done the non- revup lower plenum and the MD 5'16 spacer. Next up I added a stock z-tube, all from Jason at www.riversidenfiniti.com , one of our sponsors on this site. Next up I'll be adding a Stillen full catback, together with a Stillen intake. I'll then schedule to get it tuned in Austin, through the folks at www.uprev.com Modified dave from modified mag has done similar mods to his 2K6 6mt. coupe. The VQ35 is a highly tuned engine, in stock form, as-is. There's not much that we can do to squeeze tons of hp out of the engine. American muscle cars, such as Mustangs or Corvettes have lots more hp that can be extracted with something as little as a K&N drop-in, not so with our Japanese cars. Hope this helps.

 

2003-06 g35
Gear ratios
6 MT

1st 3.794
2nd 2.324
3rd 1.624
4rth 1.271
5th 1.000
6th 0.794
Revers: 3.446
Final drive: 3.538

2003-06 g35
Gear ratios
5AT

1st 3.540
2nd 2.264
3rd 1.471
4rth 1.000
5th 0.834
6th -
Revers: 2.370
Final drive: 3.357

Her is the most recent dyno that i have of my car

here is another one from a modded rev-up


let me know if u need anything else.

 

30-40 with a good tune. (I'd consider some thermal management on the intake though).

 

What are the specifics on these two dyno charts.

Year, make, model? Before mods, tuning? After mods, tuning? Gear of pull?

 

first dyno is mine and the red line is before the tune dyno with kinteix V+ plenum, custom exhaust and Z-tube. It looks like the pull was on 3rd gear.

second dyno is from a 2007 G35 coupe 6MT and it has MREV2=5/16 ISO SPACER=GREDDY EVO 2=JWT POP CHARGER=Z HFC METALLIC=. The green line is before the tune and the yellow line is after the tune. from mph it looks like the pull was done on 4rth gear.

 

bump.

 

I have optimized the shift points based on Klubbheads dyno chart. I will not vary much with basic bolt-on mods. I will post details later on solution finding, but results are

1->2 7400
2->3 7100
3->4 6800
4->5 6800
5->6 6750

Enjoy.

 

^thanks a lot. When u get a chance, post the methods the way u figured it out. I will try that next trip to the track. Are those RPMs based on the tach or based on the actuall RPM. I can technically go to 7400 rpm but because of the 3-400 rpm difference between the tach and the actual RPM, the real RPM are going to be 7100 rpm.

Thanks a lot again.

 

I should have made some comments regarding those numbers. First the power curve is extrapolated out to 7400. Data only goes to ~6800. This is why I always stress to dyno pass redline. How accurate is the power curve equation, past 6800. Probably not that great, and my guess is power would drop of more severely, leading to a downward shift of 1->2 shift particularly.

To answer your question, this is actual engine speed, NOT tachometer reading if there is an error in tach readings

Another thing to not. The ECM I believe will shut the fun down well before a 7400rpm I believe. I don't know what that engine speed is, but I believe the fuel is cut somewhere just north of 7000, or maybe it is 7k if this tach error is that severe.

It will be tomorrow at the earliest for the details. I got it at the office.