lobuxracer

iTrader: (2)

I made this one. Spreadsheets rock for some things.

Joe Z

iTrader: (10)

In JAPAN....... they offer the HKS Velocity Advanced Computer for the Japan Spec IS-F

VAC Type ISF - 45002-AT010 - ¥157,500 (approx $1,600 USD)




There has been NO confirmation if this product will work on a US Spec IS-F...

Time for one of you guys to research this some more..

Joe Z

agtuning

Hi, didn't MHP remove the governor speed limiter on the ECU reprogram?

lobuxracer

iTrader: (2)

The raised rpm limit and speed limiter removal have not be successfully tested and proved to work yet.

btwanky

messing with the RPM range to me sounds like a horrible idea... the transmission shifts so nicely anyways... i personally dont think its necessary.. if the transmission blows.. i bet its prob like 10,000$ to reinstall a new one..

ISFer

iTrader: (2)

Very good charts, guys but I don't see the rear axle ratio.
I'm guessing it's about 3.5:1.....
Anyone know for sure?

Colin.

flowrider

iTrader: (9)

Again, according to Road&Track. Direct drive (1.00 to 1) is sixth and the axle ratio is 2.94:1

Lou

ISFer

iTrader: (2)

Thanks Lou, I missed that . My bad.
I didn't realize the rear gear was so low. It sure wouldn't hurt hwy mileage much to go up to a 3.5 or even a 4 to 1 for even better low end performance.

Colin.

Cabinetman

I have a feeling 4.00 or more might be a bit much even for drag racing. In the Mustang world 4.10s are a common mod for guys looking for quicker 1/4 mile times when their cars are still making close to stock power. The thing I noticed is most guys go back to 3.55s when they start getting north of 400 rwhp because the car can't hook up in first with 4.10s and they need an extra shift to run the 1/4 mile.

Gears are one of those things that really have to be setup based on your needs. A guy who just drag races will want a setup different than the guy who does track days twice a month.

Please don't let me talk you out of gears. I would love to see some real world data on gear swaps in the F. If you do it find a good shop. You don't want to end up with gear whine.

ISFer

iTrader: (2)

Me too. My Mustangs ran with 3:73's -- suited me to a tee. The F with 4 more gears would seem to want a deeper rear gear to make use of more of them.

I'd love a rear gear but wouldn't want to mess up my warranty so probably won't do the change.

Yes, ring and pinion settup takes some expertise. You definitely don't want a rookie doing the job for you...

C.

lobuxracer

iTrader: (2)

It's on the chart. It wouldn't work if it wasn't there.

TIRE SIZE
TIRE DIAMETER
TIRE CIRCUMFERENCE
NOMINAL TIRE WIDTH
BASE RPM & MPH
INCREMENT
FINAL DRIVE RATIO

Here's what the chart looks like with the IS350's 4.083 rear gear:


Looks like a quarter mile run will get into 6th gear.