finding the right gears

[WRENCH MAN]

With the 152 and the OD I'd say 4.56's, 4.88's wouldn't be out of line either for that matter.

[BIGROTT88]

Originally Posted by WRENCH MAN

With the 152 and the OD I'd say 4.56's, 4.88's wouldn't be out of line either for that matter.

He cam back to state he has a 304

[Eric VanBuren]

Originally Posted by BIGROTT88

He cam back to state he has a 304

No that was the guy that suggested the steep gears the truck that is the subject of this thread has a 152 and an OD hence the suggestion of the 4.56 or 4.88 gears.

[BIGROTT88]

Originally Posted by Eric VanBuren

No that was the guy that suggested the steep gears the truck that is the subject of this thread has a 152 and an OD hence the suggestion of the 4.56 or 4.88 gears.

Oh wow I missed that one

[Tucker H]

Seen a similar set up on a 4banger s-10, buddy had granny 5 speed on it, real nice, matched with a lift and 35X12.50s, made for the mtn...... running i think it was 3.05 gear.... broke everything you could imagine over and over in the mud, now i know the differences in cebby and IH but im using him as a reference. But on the interstate well he is proud of his speeding tickets.

[kb'sforme]

i understand what everyone is saying. I'll be the first to admit I'm not a 4x4 guy and I'm not up on gears and such. thats why i have a drive line guy! that said you can understand why I'm asking. i know there are math formulas to figure it out, but not sure i would fully understand the answer. goals here are to get the truck to take off well and be usable in daily traffic so light to light take off is important. 4.10 or 4.56 would certainly get that job done making the little truck feel peppy. but it also needs to run 75 MPH with out straining the motor, that was the main goal out of adding the OD unit. i have no idea how much effect it will have on the ratio though. to be honest i haven't got to that point yet. that info may be included with the OD paperwork. but the time has come to get the axles setup the way we want them. the housings are torn apart and getting cleaned up right now! have to figure this out soon. i realize there is not perfect ratio to do it all. you either get good grunt or good top end. just want to find that middle of the road ratio. 3.73 was just a guess on my part. 4.10 would make sense. i might be concerned for a 4.56 unless those of you in the know don't think it would be too much taken away from the top end.
can someone explain having to change the carrier? i know what it is. just didn't know if you change to far either way on gears you had to change it. thought the only reason to change it was open, limited, locker,etc.

P.S. the original goal for this drive train was that in town driving the OD would not be engaged. only for flat out highway speeds.

[Comanche Scott]

Hey Jared,

Here is the best gear calculator I have ever found on the net. Very easy to work with. If you want some help with it, drop me a p.m.

The best gear calculator I've found

The physical size of the gears are different at the carrier break point. So the carrier assembly has to be physically different to maintain the ability to get a good pattern.

FWIW: I'm in full agreement with Carl and Eric. Based on my buddies '62 Scout with 152, 4 Speed, 4.27 and 31" tires.
At least 4.27s. If the O.D. is anything better than .80:1, I'd go steeper (Like a 4.56) .
There is a lot of revs and power to be had with some head porting, and port matching work. My buddies engine can run 3,200 rpm all day long, and get great fuel mileage.

Hope this helps.

[db1115]

If yall dont want to change carriers...just buy "thick" gear sets instead.

[Jay Tabor]

any vehicle will 'take off well' thats why transmissions have gears..... LIKE 1ST GEAR!
the thing to be concerened with is keeping the final drive rpms in the torque and horsepower curve the engine produces . . . .

[kb'sforme]

well thats the big mystery. this motor will have port work, higher compression, and EFI. i doubt we are pioneers in any way. but there are not a lot of other engines like this to compare it to. so we will figure out the rpm range it likes once its up and running.
I'll try and find the ratio info on the OD unit. as far as buying gears. I'm thinking for budget we would rather try and find some junkyard units to swap in for cost. i know that is a risk. but not sure if we can swing new gears and carriers. but thats another discussion.
thanks for all the help. when i get a chance I'll play with the calculator and see what comes out. thanks for all the replays so far.