98RedBird

iTrader: (77)

Is it simply because they take more effort to turn? Bigger/heavier axles/differential/etc...?

I do know that my MWC takes a bit more effort to turn over by hand when spinning the pinion than my 10 bolt does. Just curious.

Thanks

pressureprows6

The pinion is fairly low on the ring gear compared to others....just makes more drag from friction but tends to be stronger from more tooth contact.

pdxmotorhead

Its the combo of tooth width, and the high rate of helix in the gear cut
which is drag.. to allow the very low pinion position compared to a
Dana/Spicer style.

I've helped dyno run a car with both a D44 and a 9" back to back, and we left the D44
in there because it got about 10 more HP to the ground than the 9" did.
Now this was a salt flat car so the drag only became critical at about 100MPH, it
got worse as we approached the dyno's top speed rating of 200mph so never
figured out the ultimate hit. Since this was a 1.5 liter car (Formula Atlantic motor in a Tacoma...)
with a turbo, it mattered where we were losing power,, we tried about 8 different drive-line setups as well.

MarkZ281979

Seems like you would use a Quick change gear .. They are weak for drag racing work fine for anything else a GM 10 bolt would be plenty strong for doing what you were doing .. You just need way overkill for a whole shot drag racing ..

01ssreda4

iTrader: (96)

simple answer, this

MarkZ281979

My 1968 FWD 6 wheel drive Truck has Spiral Bevel gears 6:167 ration the previous years were Hypoid gears.. They say Spiral Bevel are stronger yet Rockwell has used Hypoid for years and Mac used a Top Loader Worm gear..

The Problem with my FWD gears is they are only about 2/3 as large as the rears in an Eaton 34,000 or 38.000 Tandem rear end which used an 18.5" ring gear and 15 5/8" bolts the FWD only uses 12 1/2 Rivets in a 38,000# rated tandem that is their C series Axle .. they made one larger axle with 16 1/2" rivets in the carrier .. rivets tend to rail so I replace them with L-9 bolts with lock nuts and lock tight .. a few years ago FWD wanted $35,000 for a ring gear and pinion .. 25 years ago they wanted $3,500 for them but a place in Chicago was making counterfeit ones and I bought one set for $1,850.00

pdxmotorhead

I think the owners concern, was, You don't go low budget on the rear end when your going to break 200MPH,, LOL
(The tacoma made 200 and change in turbo trim.. )
Also the plan was to do it once with the motor N/A and then go Mild turbo, then go all out turbo.

And for the class iirc a full floating rear axle is mandatory, cheapest one you can buy is the one out of
a Dolphin Motor home.. Full float outers on a D44 axle..

MarkZ281979

I think the Majority of cars at Bonneville use Quick change.. You can weld a Full Floater Bering set on almost any rear end Moser does I am sure Currie does it All Round Round cars use Quick change with the exception of the low budge classes and Nascar.. Why NASCAR still requires a 9" I really would not know with out researching as it would actually be cheaper to use Quick change

Sprint cars are 900 HP Indy Cars use Quick change and so do Formula 1 I would assume .. Circle track racers might change their gearing every weekend if they are on a different track
http://www.moserengineering.com/de8f8ec067eb17018bd7005bacc0ac0b.dept
I did not change my font strange ..What is the Hp /Tq rating and what else is needed to complete the rear end? Thanks
https://static.speedwaymotors.com/images/charts/91714_Chart.gif

https://www.speedwaymotors.com/Winters-Modified-Quick-Change-Rear-End,8517.html
Asked by Z 3 years agoAdd your answerVerified Reply - CharlesI apologize, I do not have a specific HP/torque rating on this rear end. However, Sprint Cars have about 800 HP and use these with no issues.

https://www.speedwaymotors.com/Winte...on,105196.html