4.56 Gears

[crouse]

Anyone running 4.56 gears? If so, can you tell me a what speed your Marauder shifts from 2nd to 3rd? And engine rpm at 60 mph?

Can I use a simple formula to calculate this? I have 4.10's and my Marauder shifts from 2nd to 3rd at about 80 mph.

4.10 x 80 mph = 328 / 4.56 = 72 mph?

Same for engine rpm at 60 mph. 1800 rpm x 4.56 = 8208 / 2000 rpm.

If I'm going switching to a Torsen T2-R differential, I might was well change the ring and pinion also.

[crouse]

I forgot to mention. When I run Auto Cross events, I run a Falken Azenis RT660 295/40-18 on a 18x9.5 rim. The diameter is 27.4" which is about 1.2" smaller in diameter as the OEM rear tire. That's about 5% difference, so I'll need to factor that in.

[daniel.drives]

https://docs.google.com/spreadsheets/d/11uVtr8miXJGQb7S6UYueXQ7b_Gjon 5ts9QQOSVikW2g/edit?usp=sharing

I made this to compare gear ratios for a 6R80 swap, but it will work well for what you want to see. Feel free to duplicate columns to the left and add different tire sizes/gear ratios at the top. You should also be able to add rows if you want to check more specific RPMs (say, 2200 in 4th gear)

If anyone else finds this link, please go to the bottom, right click the tab that says "Original", hit "duplicate sheet" and rename for yourself

Also note that tire size is input as revs per mile, but there's plenty of calculators for that.

[crouse]

So it look like with 4.56 gears and my Falken 295/40-18 tires, it would be 72.5 mph at 6500 rpm in second gear?

[Comin' in Hot]

I can't help you with your question, but if you install 4.56s youre going to need a notched cross pin. I figured I'd mention it so that when your 95% done with the install you don't get stuck not being able get the cross pin past the ring gear.

[crouse]

Thanks for the heads up.

Installing a new carrier and ring & pinion, I'll need to find a shop to do the install.

[justbob]

4.30’s fit fine. I was quite happy with mine.


Sent from my iPhone using Tapatalk Pro

[crouse]

When running Auto Cross events, I typically start in 1st gear then shift to 2nd and run the entire course in 2nd gear. In some areas of the course, I'm down in the lower RPM ranges and with 4.56 gears, I'd be in the mid to upper RPM range.