Thinking About Gears...

[RedLariat85]

I'm considering putting 4.56's in my 85 F-150. How many RPM's will it be turning going 65 with stock tires?

Anyone else run these gears? If so, how's you like them?

 

[DNFXDLI]

I have this calculator bookmarked:

http://www.csgnetwork.com/multirpmcalc.html

 

[RedLariat85]

I have this calculator bookmarked:

http://www.csgnetwork.com/multirpmcalc.html

Thanks!! It'll be running 2262 rpm's at 65..Not too bad.

 

[DNFXDLI]

Overdrive helps huh?

 

[RedLariat85]

Overdrive helps huh?

Oh yeah! for sure!!

 

[LEB Ben]

Overdrive helps huh?

Oh yeah...forgot about the overdrive...I was ready to get all jumpy when that 2200rpm number was posted. I can relax now.

I'm considering putting 4.56's in my 85 F-150. How many RPM's will it be turning going 65 with stock tires?

Anyone else run these gears? If so, how's you like them?

What exactly are you looking to do with that kind of gear? I have 4.56's in Thunder with 37's and an E4OD. While lower than the 2600 rule of thumb I shoot for, I still don't think I'd make the swap if you're going to be spending a whole lot of time on the highway.

 

[RedLariat85]

Oh yeah...forgot about the overdrive...I was ready to get all jumpy when that 2200rpm number was posted. I can relax now.



What exactly are you looking to do with that kind of gear? I have 4.56's in Thunder with 37's and an E4OD. While lower than the 2600 rule of thumb I shoot for, I still don't think I'd make the swap if you're going to be spending a whole lot of time on the highway.

I'm just looking for really quick acceleration..and I'll probably take it to the drag strip a few times this summer. I wont be driving it on the highway too much..mostly city and rural driving.

 

[Beach66Bum]

I have a 351 windsor with the t-18 trans. with 4.10's and at only 55 mph the rpm's are at just under 2500. Not so good for gas mileage. Wish it had overdrive.Tires are factory size. Upside, great low end.

 

[5.0Flareside]

4.10's dude.. 4.56 unless with bigger tires is over kill... loved the 4.10 gears in my Flareside...

 

[DNFXDLI]

Nothing wrong with 2250 rpm at highway speed...4.56 will give you some good acceleration.

 

[FordF-SuperDuty]

Nothing wrong with 2250 rpm at highway speed...4.56 will give you some good acceleration.

Heck that's about what I do at 70 with my 302 and 3.55s.

 

[LEB Ben]

Nothing wrong with 2250 rpm at highway speed...4.56 will give you some good acceleration.

I 100% agree with that Duncan, my only concern was with the added potential unnecessary stress. In the end though, it's probably only about a 600rpm difference.

 

[RedLariat85]

I 100% agree with that Duncan, my only concern was with the added potential unnecessary stress. In the end though, it's probably only about a 600rpm difference.

Yeah, I'm set on getting 4.56's..It'll be worth it! Should be pretty quick with them. What stall converter should I go with....2000 rpm?

 

[DNFXDLI]

You would be best off talking to a converter place...generic converters can have lots of variation of stall speed depending on many factors...cam, displacement to name a couple.

 

[Truckin4life]

Im not even going to get into it. We could spend many hours on tq converters call up supplier tell them exactly what you want and what your using and they will hook you up

 

[FordF-SuperDuty]

Apparently these guys are the leaders in AOD products.
http://www.lentechautomatics.com/aodproducts.html

 

[5.0Flareside]

Thanks!! It'll be running 2262 rpm's at 65..Not too bad.

just realized this, but theres no way...

my flareside with stock height tires was turning 2800 at 70..... the overdrives are geared differently compared to the AOD... but NOT THAT DIFFERENT!!

 

[Truckin4life]

65 would bring you down to what 2600 area?

 

[FordF-SuperDuty]

just realized this, but theres no way...

my flareside with stock height tires was turning 2800 at 70..... the overdrives are geared differently compared to the AOD... but NOT THAT DIFFERENT!!

That's what I thought, the number seems really low for 4.56s!

 

[5.0Flareside]

im finally feeling good enough that i noticed the numbers being not quite right...