I contacted the dyno owner / operator as mentioned before, he said:

"My apologies for the late response. Unfortunately, I am unable to supply you with a tacho graph as I did not set the dyno up for tacho. Please do not hesitate to contact me for further information at your convenience."

It is a dyno dynamics dyno but i am inclined to go with what he says in this case as he has alot of experience and its not like I can tell him anything else and get a good outcome. I cant see why the computer shouldnt be able to convert the kph to rpm though?

I have a dyno in kph, but by looking at what gear I used we should be able to work out the rpm. Peak power would not be at 8k but it should be close with the power not dropping to 8K. When I get home I will scan the kph.

 

You sound like a smart ****

Alot of Au tuners tune in kph and my tuner was no different. The dyno is a tuning tool, so once a car is tuned there would be no requirement for a tuner to then run the car again over rpm. I assumed he would print one in rpm or we could convert it later. I was satisfied because I could see the engine reving to 8000 and the chart being graphed, as I was in the car. With me satisfied there was no one else to worry about.

Ignore power figures as this is sans-turbo.

This dyno is before I installed an APS 2.5 true dual. I changed exhausts as I believed my previous y-pipe configuration to be a restriction at high rpm. After the exhaust install I had to add more fuel in the last 1000rpm as it had leaned out a few decimal places.

Looking at the dyno...
Where the power stops should be just before 8K. Seems like peak power is from 7400-7600rpm with slight drop towards 8000rpm.





FYI Ive edited numer plate.

 

Not to be a d!ck, and you surely dont have to prove anything to people online, but that dyno could be revving to 6500rpm's for all we know-regardless of what you remember seeing him pull to. While you may have successfully made power up top, I still havent seen a legit dyno-meaning an rpm reading on the bottom on a respected dyno(like the on your on)-not some cracked out Dastek. I find it a little hard to believe he cant change the settings, maybe he's just lazy?

 

We would need to know his rear tire size to do so. Or I guess we could convert it to MPH, and knowing his FD (likely stock) and tire diameter we could figure out the speed/rpm's he's doing in 4th. Ugghhh I suck at math...

 

the speed is close to 110mph.

 

Ok, so close to 110mph in 4th assuming he is stock sized or similar to stock tire and the stock 3.5FD is roughly 6400-6500rpm's. At 6600rpm's in 4th gear a 6MT Z will hit 112mph. So judging by what you say tig he is no where near 8000rpm on that dyno, and you can see his power is starting to flatline/fall. Still waiting on a legit 8000rpm PULL!

EDIT-found a KPH to MPH conversion calc online, I put in 187-190KPH as he hit on that dyno where he claims 8000rpm's. It comes out to 116-117mph, and that is right around 7000rpm's in 4th. Good pull no doubt, not to take away from the OP, but Id doubt it would make power near 8000 or even 7500rpm's....

 

I don't really think the Tomei 268's aren't aggressive enough to give peak power at 8000 rpm by looking at the dyno. Even if the cams were big enough I am willing to bet the intake would be the next limiting factor.

 

You wanted a dyno and this is what I have after the tuning process, live with it.

I find it hard to believe as well. Maybe he is, maybe he wants me to run it again so he can make more money? Who knows, its out of my hands.

 

I am living with it, no need to get upset. You claim one thing and your dyno shows another, that is all....

 

More like 118 mph if my calculation is close.

 

I said in my post he would have let up before 8000rpm as that is where the limiter would be. 193kph is 120mph, so what does the calculator say 120mph is rev wise? Should be 8000rpm.

Im using stock 3.5FD, with 275X35X19 tyres.

These have a 26.57 in diameter and a 83.47 circumference.

I just tried the calculations manually and through an online calculator using this forumla:

RPM = (diff ratio * (mph * 88)) / (tire circumfrance / 12) * transmission 4th ratio

RPM = (3.5 * (120 * 88) / (83.5 / 12) * 1.271

RPM = 6743!???

Am I doing something incorrectly with that calculation? I dont think I am as I got the same result from an online one. Therefore that chart can not provide the correct information, so I have removed it to avoid confusion.

Seems only my tuner and I will be able to look at it and gain any knowledge as we were in the car when it was reving to just before 8K and producing that result on the dyno. But I dont really care about anyone other than those two people.

I have since installed a new exhaust and am in the process of road tuning it. Once this is complete I will probabally hit the dyno once more, this time I will request an rpm based dyno when we are done tuning... want to chip in for the cost? j/k

I know it is not making peak power @ 8000rpm, I would say peak is around 7500-7600rpm. Well over 7000rpm and pulling strong to 8000rpm. I plan to tune the boost curve over rpm to further the quest for tractable power, this should also be able to move peak power a little higher should it be required during the FI stage. I dont think it will though as you generally want it to slow a bit before the rev limit so you dont bash into it.

 

sorry that was just a quick calculation off the top of my head.

 

Any update on this?! I want some videos of this engine revving up to 8krpm.

-Acree

 

Ive been through 3 exhausts total not including the stock one trying to find the right one and I currently have my stock exhaust back on till I can find another. So exhaust wise its pretty quiet but it gives you a chance to hear the motor in full song. Once I find a suitable exhaust I will take some clips.

 

Awesome. I look forward to it!

-Acree

 

Other than more aggressive cams and higher compression what would you have done differently?

 

nice post. looks like it came out good. lets see some vids!

 

looks great, any idea of the cost so far?

 

I have a question why would you use high silicone content pistons? Higher silicone content makes pistons more brittle than a zero silicone forging...

 

1. It's silicon, without the "e" at the end.

2. High silicon forgings are plenty strong for the power levels he's aiming for. I'm sure he wanted it like that for their relative dimensional stability.

3. He purchased the extreme duty design.