https://my350z.com/forum/engine-and-drivetrain/301451-4-083-gears-final-drive-installed.html

According to aceman's math its 101 mph in 3rd. So its up for discussions lol.

TK

EDIT: NVM, he used 255/45/17 tires, I used 245/45/18 (the stock 07 rear tire size)

 

^^^ 101 looks right to me.. not that I've done it a hundred times or anything

 

Here was the original thread. Keep in mind we are not doing mathematical calculations of tire size and gear ratios. He was just going off whatever the speedometer said.


https://my350z.com/forum/2003-2009-nissan-350z/268105-07-z-review-in-comparison-to-my-06-z.html

 

I dont know about on the street because I havent tested it on the street and paid attention but I generally trap 106 and have trapped a few times at 107 in the 1/4 mile and Im generally well into 4th gear.

 

Okay, sorry but no pic, it was fuzzy... I managed to get the digital speedometer to read as high as 104 mph, but that was also bouncing off of the rev limiter and you really don't want to do that at the track because it costs you time. But I'm sure there's also some error in the speedo too. I've noticed that it seems to read about 2 mph faster than what those speed signs with radar guns tell me I'm driving when going around 80 mph. So I tend to agree with the 101 mph that was stated. That still means 4th gear in the 1/4, so don't try to play that card, lol.

 

given that 2 mph difference at 80 would you agree that at 160mph on the digital speedo your probably actually doing about 155?

 

Yes, but it's still governed at 160. Maybe it's 155 with a radar gun, but the speedometer still says 160. You can correct this by increasing the size of the tires because speed is measured by the rpm of the tires. If the tires are larger in diameter then they have a greater circumferance which means more distance traveled per rotation. Hence, greater speed with fewer rotations.

 

Here is a overlay of a HR engine with a few mods and my DE engine with everything but heads and cams.

https://my350z.com/forum/engine-and-drivetrain/328813-dyno-overlay-of-a-07-and-03-same-day-same-dyno.html

The HR engine is a far better design then the DE engine. But it should be, it has been 5 years now.

Later
Todd

 

great, so if you put monster truck tires on your z it will be governed at 500mph. sweet

 

My NISMO topped out at 160 on my SPEEDO when it hit the speed limiter. My TomTom showed 154-155 mph at that speed.

 

I know because the car is governed at 155 actual speed. It may say 160 but thats for the sake of the speedo showing as maxed out.

 

The car is governed at 160 not 155. The SPEEDO reads what the ECU is reading and that is 160. GPS will always be the accurate speed like a radar gun.

 

Speedo's legally have to read high.

 

not really with only 1300 i could beat ya preety bad in ur stock HR and less money from off the line so i dont get your point. Really when where going FI does your HR make u any superior. So then take the cockiness away and lets enjoy the Z.

Also its not about just not enough mods for the HR

HR headers are equal length preety much no improvment can be made
intake is preety much topped out
exhaust ..ur using whats out
pulleys um....yea not much intrest

your car is maxed out preety much...until FI comes out or a ecu at least enjoy ur 4 mods man. And lets move on

theres a reason why the nismo Z has no improvement mods for NA because really nothing is gonna be better then a exhaust and gearing in the 3.5HR . SO stop whinning. lol


God please come out with the 3.8RS so i can really get a Z worth upgrading to sheesh. But i do loooove the nismos suspension mods very worth it in my opinion but i wouldnt trade at all for anyhting else then a 3.7 or 3.8 RS Z at this point. My engine doesnt consume oil with the v2 and im clear to go with mods.

But yea in the end who cares...the person with the bettter mods wins.

 

What a tool... Do you have any common sense at all? Judging from your posts that I've seen I'm going to require proof if you say you do. How much of a difference in tire diameter do you really think is going to be required to correct the speedometer at those speeds?

No, that's the error in the speedometer. Nissan could adjust it and make it correct if they wanted to, but why? The way it is right now people will think they are going faster than they really are, which helps for speeding tickets so long as you're not speeding heavily. If you're doing 5 over, then in reality you might only be at 3 or 4 over. Less likely to be stopped. As for it being off at 160, who cares? It's not meant to be a precision gauge of your speed, just a reference.

That statement makes absolutely no sense to me. If they only wanted to make the speedo maxed out when the car was maxed out they could've made the speedo read 155 instead. My Camaro was the same way. It was off by a few mph at those speeds. It's just error in the setup, nothing more.

If you say otherwise then post a link to a page from Nissan where they explain why the speedo is off, or else it's nothing more than speculation...

 

yea the dig speedo is def off, but hes right its refrence speedo not to be as accurate as the tac

 

Where is the argument coming from we are arguing the same point? You say the car is governed at 160 at the ECU right? You agree the speedo is errored and reads high right? So I argue that the ECU is governed at 155 actual speed which would read 160 at the "errored" ecu! WTF! You argue with everything that is said on this forum as if your the end all be all and we are fawkin agreeing with each other. Slow your roll home skillet and chill out! Just in case your arguing because you read posts fast... again...

WE ARE AGREEING ON THE SAME POINT!

 

by the way your right on the last thing. it is just speculation as to why nissan would do it for the sake of maxing out the speedo. But I didnt realize that I had to provide parenthetical documentation to prove a point that really aint that damn important... 2 me anyway

 

about the difference between a really stiff sidewall and a little softer sidewall

 

I read your post and I even just read it again. It still sounds as if you're trying to argue the point, which is why I posted what I did. If I misunderstood, my bad.

I don't argue with everyone, only some of people who are wrong, who are asses, or who take a stab at me (if I argued with everyone on here in those categories I'd never have time to sleep). I started requiring proof of things because of all the idiots who make posts contrary to the facts and the only proof they provide is, "because I say so". "This car is faster because I say so". "This engine is better because I say so". Blah, blah, blah... Cry me a river.

This is the first car forum I've ever been involved with that had so many hateful *******s. I guess it's starting to rub off on me... You don't see this kind of bickering at the Mustang, Vette, Viper, etc.. forums. A little, yes, but not on every post in every forum like in here. For the most part they all stick together and bash people with other types of cars. But people here seem to stick up for people with other cars and bash the people with the same cars. WTF?! It's like a royal rumble. Maybe I'll go back to just reading and not posting.