Hi Speed rear end For flathead Questions??

DICK SPADARO

Well-known member
Ok I need some input and I need a bunch so here is a time to get some of your ideas in new product development. Say a guy needed to perk up the hi speed cruising performance of his flathead powered car.

Would it be better to offer just a high speed ring and pinion gear.

Or

Would you like a complete banjo with pinion installed so you just removed your old center section and reinstalled a new one with a better gear ratio using your differential section overagain.

What would be a good ratio to develop?

Last what price range would be acceptable knowing that it used european gears and a USA machined case and knowing that a high speed gear set already retails for around $350.

Id like to get some input on this over the weekend so Please feel free to post to this thread. I need as many responses as possible for a good sampling so even you guys that are quiet a response would be appreciated.

Thanks DS
 
I think there might be a lot of questions that need answered before a person would buy one.
Shipping costs
How much driving
Can you set up your own ring & pinion
How about bearings
What gear ratios
Core deposit on the banjo
I would just opt for the ring & pinion set
I spent a ton of money on putting a 4L60 in my roadster trying to get increased mileage. Bought the factory GM performance ****** & shifter,then the ring & pinion, then went to smaller tires to get the engine in the power band. I could have bought a lot of fuel for what it cost & the increase wasn't all that much. Then the gas prices went sky high so now I don't run around the country as much as I did before. I really like the change tho as the RPMs are lower & the swan neck shift lever looks kool & the low really gets you going in a hurry. I have to be careful as to not over rev when taking off if I'm showin off. Heh heh he:D
 
To me, it seems the tough combination is the 1932-34 stock rear end. Seems all were 4:11s and with using the after-market 10 spline 3:54 gears, modifying a drive shaft, machining the gears and coming up with the other required original 32-34 rear end parts needed, can get spendy.
Another way is to use 1936 and later axles, housings, banjo and then you don't have to machine the gears but still need to modify the drive shaft and torque tube and grind the straight spring to fit the bent spring cross-member.
An easier/cheaper way would be nice.
 
I would be tickled pink just to have 3.54's for 32-34 rears that actually are made like the gennies and actually fit with all the stock parts . The stuff around now is a PITA !!!!.
 
To qualify my response, I presently drive a flathead powered '40 cpe with a Lincoln 3 speed with overdrive & a 3.78 rear gear. I also have a 3.54 geared Mercury.
Prior to these I drove a cpe with a 3 speed & an 8" 3.40 gear with a flathead engine. All this brings Me to the conclusion that a GOOD flathead will pull a 3.40 gear without OD down the road really nice & comfortable.
Install the pinion in the housing, then anyone can complete the rest.
If you include the bearings, seals & gaskets with the installed pinion & keep it under a grand, I think it would work.
 
Would you like a complete banjo with pinion installed so you just removed your old center section and reinstalled a new one with a better gear ratio using your differential section over again?

I don't think you can swap out a "center section" like it was a pumpkin in a 9" Ford rear. The carrier rides in the axle housings and that's where all the fun setting up the gears lies.
 
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Hi Dick, If I understand you right, A complete banjo with the pinion already installed would be nice.
Probably in "kit" form with new bearings, races and shims. So I get the banjo and assemble using my differential section and axles.

I think that this would make things much easier for the guy who wants to do it himself but may have difficulty setting up the pinion.

Ratios are tough. A stock engine may not want to pull anything more than the existing 3.54. I don't believe there would be much call for anything higher to make it worth while.

With the gear set and machine work I would guess at under 750. In a kit as I suggested probably under 1000. But, I really have no idea.

I have put higher gear in my 34' and that was a PITA but came out satisfactory. I think that a guy with less mechanical ability couldn't do it. Also I have 3.54 in the 35' coupe that I robbed from a 46' Ford rear and used a 39 driveshaft. Butch
 
A complete banjo with the pinion already installed would be nice.

Except for setting the pinion bearing preload, installing the pinion isn't all too hard. (Put the pinion in the freezer and the banjo in the oven for a bit.) It's the carrier bearing preload and ring gear backlash that are tough. And, it's easier to set up the carrier bearing preload BEFORE the pinion is installed. (IMHO)
 
I would prefer a gearset. As you know Dick, one gearset would not fit all early Fords, so three or four different ones would have to be available. Setting up a new gear in the diferential is not rocket science and easier than lots of engine work, so most people with some mechanical ability can do it. PeteV8 is correct about swaping out a center section and for me, changing the ring gear and pinion would be the choice. I do not know about price, because I just look for 46 rear ends and their 3.54 gears. This will fit 37-48 and 35-36 with some additional work. For 32-34 I agree with David J. A good stock engine pulls a 3.54 gear just fine as others have said. I have driven a Dearborn class 39 coupe with a 3.54 gear all over the country and it works A-OK.
 
Stock Ford gears seem to be easier to set up than some of the after-market ones. I strongly suspect this is due to machining tolerances. That said, I'd vote for a well made gear set, sold as part of a rear axle rebuild kit with good quality parts. It seems like a ratio between 3.25 and 3.50 would be appropriate and if the cost could be $750-$800 it would be a "deal". It might be wise to really define both the market and the competition. FWIW
By the way, great idea.
 
For me personally, I would not won't to buy a ring and pinion gear with the pinion already setup in a banjo housing because I can do this setup myself, plus the more difficult issues of carrier bearing alignment and gear mesh still exist. Speedway has 'set the bar' on cost for a R&P gear set at $350.00, so, I would not want to pay more than that unless there was some other benefit(s) for me, i.e., a pinion with a 10 spline shaft that requires no modifications to the existing driveshaft.
If I were personally developing a new early V8 gear set, one goal would be to make sure these new gears will fit all banjo rear housings from '32 to '48, requiring no modifications to the banjo housings or ring & pinion gears. With 3.78, 3.54, and 3.25 gear ratios already available as new reproduction parts, I do not see a real need for other ratios, except possibly something between the existing 3.78 and 3.54 ratios.
Again, this is all just my own personal opinion....fwiw.
A big thanks to you Dick for being in the business of suppling parts and services for our early Ford V8's!!
 
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Effort for a new product such as a torque tube adapter kit to install a Jeep T5 transmission to a 32 to 48 torque would would be a better project since the suggested project is already pretty much covered.
 
From what i have heard on the grapevine, the 3:54 in an original 32-34 is a bit too high, and without any doubt the 4:11 too low. I am in the process of installing 3:78 that were not available for the 32-34. The gear set is out of a 35 up, so all the modifications have to be done to the gear set as well as the differential housing and the drive shaft. A good set of 3:78 or the 3:54 that fit the original housing and the drive shaft would be great, The current price point is OK.
 
I converted my 32 Tudor to 3:54 rear end ratio and drove from Ma. To Hood River meet and it worked fine with a stock 35. engine . My friend who was with me ran a 34 Tudor all stock was able to drive some hills in 3rd when I was in 2nd! I also had a 39 ****** set up which made shifting easy. Just info if it helps. Kerk
 
If you can rebuild an engine, you can rebuild a banjo. Just takes a little time. These rear ends were build many years ago, many of us have better tools and gauges for checking back lash etc. than they had back on the day. I personally would like to see a better axle, just to make me feel better.
 
I converted my 32 Tudor to 3:54 rear end ratio and drove from Ma. To Hood River meet and it worked fine with a stock 35. engine . My friend who was with me ran a 34 Tudor all stock was able to drive some hills in 3rd when I was in 2nd! I also had a 39 ****** set up which made shifting easy. Just info if it helps. Kerk

Where you will really notice the disadvantage of 3:54 is in city driving with stopping and starting on hills. Could even cause a snapped axle in an effort to spin the wheels to get moving. Changing the trans gears to 29/15 with the 3:54s will help but then shifting down to 2nd on a steep hill is a bigger jump. It's all a compromise and where and how you drive them.
 
I have a Columbia and I would use it rather than a single rear gear ratio; unless there was a 5 speed conversion that used the torque tube ( similar to the setup that was described above).
 
Dick Spadaro,
Learning not to be so quiet: thanks for invite to speak.
We backyard background lowbuck FlatForders work around gear options/mods
via a selection of wheel/tire sizes/diameters available to switch for trip, event , load, project, experiment etc.
Next is to swap complete rear assembly---have a selection of these on hand too.
Next is scrimp, save, trade and find a way to buy your products.
I strongly support your venture & effort & risk you are considering, you Ford Guy!
Hope this helps. You're the Man!
Good work is Fun!
Gene Tulsa
 
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