Top speeds of Manual / Auto

[Esoteric]

Can't remember what Brad said but wasn't along the lines

269 km/h @ 6500?rpm (A)
233 km/h @ 6500rpm (M)

those speeds without electronic limitation obviously.

Just out of curiosity, what is involved to remove the limiter?

 

[bradc]

just cut one wire! ask Kenneth about it.

As for the top speed, the stock VR-4 produces it's max power at 5500rpm. Therefore you would want the gearing to be setup so that the max speed is at the 5500rpm mark in 5th. Unfortunately Mitsi designed the car for driving around town and not for long open road drives, this is especially evident in the manual where you spend most of your time on the motorway at 3000rpm!

I would say that in a perfectly stock car without the 180kmh speed cut, the manual would do about 240kmh 6266rpm and the auto about 250kmh, about 5600rpm.

With modifications like my car, or even boost + exhaust + intercooler, I would think you would be able to push the auto to about 270kmh at just over 6000rpm, while the manual will never get that high, it's limit at 7000rpm is 267kmh, and power starts dropping off rapidly above 6000rpm anyway because of the tiny turbos. I doubt a manual VR-4 with stock turbos and stock gear ratios would ever get much above 255kmh.

If you change out the final drive to a 3.722 unit and put in a 0.721 5th gear (instead of 4.111 and .761 stock) you have almost the same overall reduction as the auto gearbox (3.684x .731 = 2.693 for auto, 2.684 for manual with 3.722 and 0.721) and they would be capable of very similar top speeds, the manual would be slightly faster because of the very very slightly longer 5th and less drivetrain losses.

Now if you had bigger turbos like TD04's then 300kmh with the auto would be very real and very easy to get to.

 

[SiliconAngel]

Oh for a 6-speed manual gearbox...

 

[BuzzPuppy]

Oh for a photo of which wire to cut Kenneth!!!

 

[bradc]

Gav - searching on cvr4 for speed cut will get you what you want

Trev - the stock 5 speed is a nice strong gearbox and the ratios are spread out perfectly. With a longer final drive like 3.722 you don't really need a 6th gear because you will be at 2500rpm at 115kmh which is acceptable.

 

[Esoteric]

Thanks Brad, I'll hit Kenny up about this later.

Some observations today on my driving mission

doing 100km/h on level surface @ 2500rpm
doing 140km/h " " " @ 3300rpm
doing 180km/h " " " @ 4500 +/-

couldn't get an accurate reading on the last one as was running out of road quickly by then.

 

[bradc]

hmm that didn't work!

1000rpm 45
2000rpm 90
2500rpm 112
3000rpm 135
4000rpm 180
5000rpm 225
6000rpm 270
7000rpm 315

 

[Guest]

Oh for a photo of which wire to cut Kenneth!!!

Here is a link for which wire to cut

http://www.clubvr4.com/forum/showthread.php?t=26059&highlight=speed+cut

 

[Esoteric]

Thanks Peter

 

[VR-04-TT]

Brad, once I'm done with the caliper brackets I'll start looking around for a final drive that we can use. I love doing this stuff

 

[bradc]

http://www.teamrip.com/NEW_EVO_STAGE_1_TRANSMISSION.html

99% sure that the 3.73 final drive here will work in our cars. He also might buy our old 4.111 gear off us for some money!

 

[VR-04-TT]

Interesting!! I'll have to send him an email...or have you already done that?

 

[SiliconAngel]

That IS interesting - so changing the final drive has cogs with a slightly altered diameter? Can you just swap out the final drive in the stock transmission, or do you need to replace the whole lot?

 

[bradc]

Paul - I spoke to him a while ago and he doesn't know what our cars are, but he can send them out to us!

Trev - you just swap out two gears, one on the gearbox output shaft, and the crown wheel of the front diff. The stock output shaft has 18 teeth on it, and the crown wheel has 74 teeth. The 3.73 they are advertising could be the same output shaft and a 67 tooth crown wheel, I don't actually know

 

[VR-04-TT]

Did he say how much they are? If they're not too expensive, I don't mind getting one. If they're expensive then I don't know if I'm ready to gamble heaps on it...which, knowing me, won't stop me anyway lol

 

[bradc]

US$1000!!!!!!!We will be able to sell our old 4.111 final drive to a guy with an evo for quite a bit of money though

 

[VR-04-TT]

Fark! I'm not ready to part with that much just yet. I'll have to save up I think lol