'64 Daytona rear end change

[wagonairedriver]

We have a 64 Daytona 4 door, 289, flightomatic, model 27 TT rear with a 3.07 ratio. It's a bit lethargic off the line (2nd gear start), and has a vibration which seems to emanate from the rear end (despite having replaced the bearings and having set the endplay a few times. I've been thinking about replacing the rear end with a model 44 TT with 3.73 ratio. Can anybody provide me with info to figure out revs at interstate speeds with this setup, and maybe what some of you techy guys would estimate gas mileage would be? We are running an Edelbrock 500 CFM, engine's bored 30 over. We're running about 16.5 to 18 mpg at interstate speeds now (and taching about 2500 to 2800. Also, one last question, would it be a good idea to change to non-tapered axles at this point, and where best to purchase? Any opinions would be greatly appreciated.
Kelly

[Dick Steinkamp]

Here's a calculator for you...

http://www.1bad69.com/calc.htm

Assuming 27" tall tires (205 75 15's) you are turning 2,700 RPM's at 70 MPH with your 3.07's. With 3.73's you'd be turning 3,250.

My guess is that your mileage would go down a couple of MPG with the 3.73's.

It really all depends on your goal(s) when considering the switch. The car will be noisier, get less mileage, and wear out the engine faster with the lower gears. OTOH, it should feel "peppier" around town. Only you can decide which is most important. I changed the 3.54's in my '54 hot rod with a close ratio 4 speed to 4.27's and am more than happy to put up with the highway revs. The car is MUCH more fun!

One thing you might consider is a first gear start valve body for your Flightomatic (it would then always start in 1st gear).

The (only) source for the flanged axle conversion for a Dana 44 is from Fairborn Studebaker.

http://www.fairbornstudebaker.com/

[wagonairedriver]

Thanks, Dick. I thought she'd be turning pretty fast with that setup. I guess I better take another look for the cause of the vibration. Did u-joints (twice), balanced the driveline, changed all the rear axle bearings, and reset the axle endplay several times. I fed the pumpkin plain hypoid gear oil (on the advice of a truly bright studebaker guy), then added friction modifiers on the advice of another really smart Stude guy I know, then talked to Garth Wilson (the smartest Stude guy I ever knew, and Studebaker dealership mechanic), and he said some Stude TT's were fine with hypoid oil, some needed the modifiers, and some would have a vibration with the modifiers! If Studebakers weren't so damn cool, I guess we wouldn't put up with them...

[Clem64]

Kelly:
I have experienced those strange vibrations that seem to eminate somewhere from the front u-joint back to the differential-rear axle area in both Studes and brand X cars also. I of course don't know your specific problem, but what has usually fixed mine is to install new engine and transmission mounts. It's worth a try.

Dean Croft
Roseburg,OR

CLEM

[wagonairedriver]

Already changed all the mounts when we rebuilt the engine, Dean, but thanks for the suggestion. That's a really nice looking '64. Do you get props from your chapter on your nice car? We have a '64 Daytona, almost completely done. Did almost everything 100% ourselves, and it's like it's invisible to our club. All the brand x car shows we take it to, people love it. I wonder if it's because the '64's look too square to Stude owners or something?

[Dick Steinkamp]

quote:Originally posted by wagonairedriver
changed all the rear axle bearings,

All 6?

[wagonairedriver]

Actually, Dick, I only changed the four axle bearings... the pinion bearings were buttery smooth, so I didn't tear it apart. Do you suppose?... If you've done one of those, does it have a crush sleeve to set pinion preload?

[Dick Steinkamp]

quote:Originally posted by wagonairedriver

Actually, Dick, I only changed the four axle bearings... the pinion bearings were buttery smooth, so I didn't tear it apart. Do you suppose?... If you've done one of those, does it have a crush sleeve to set pinion preload?

I haven't done one myself...not enough talent for that . They do have a crush sleeve, however.

It looks like SASCO still has some NOS 27 rear ends in inventory.

[cstude1]

Has anyone found a part number for a crush sleeve? All I find are shims available.
Thanks,
Chuck

[StudeRich]

Since you have the wrong rear axle for that engine, I would not spend any money on a model 27, just put the correct 44 rear end in the car.
Otherwise it's only a matter of time until you tear the spider gears out with a larger 4Brl. with 305-310 Ft. LBS of torque!

StudeRich
Studebakers Northwest
Ferndale, WA

[doug]

I had a vibration in my Lark that I could'nt fix till I found the bell housing bolts were loose. The problem showed up again a couple of years later.

[wagonairedriver]

Doug, I'll check the bellhousing bolts. Rich, we drive like old ladies, so I don't think we'll actually leave any parts in the road... Although my mom (at 75)still enjoyed doing burnouts in her '71 Continental! She got pulled over by a cop, and we were trying to keep a straight face, while my 5 foot tall senior citizen mom tells him she thinks maybe the car has a carburetor problem. good times... anyway, yeah, we should just put in the right rearend. Only problem is the one we have "in stock" has 3.73's in it. Maybe we can get somebody who wants to go quick to trade us one that goes fast!

[casey]

Hey WagonaireDriver: I have a '64 Challenger 4dr. A few years ago I switched out the 27 rear end for a 44 dana TT. I discovered that I had to have the drive shaft shortened 3/4", because the 44 is just bigger than the 27, and 'sticks out' further forward. So keep that in mind.

My 44 TT is 3.31, and I went with the first gear start valve body in my Flight-O-Matic. My mileage is about 15 on the highway. I also have a 289 with 500 cfm Edlebrock.

I would strongly recommend the first gear start valve body. Fun factor goes way up for around town driving.

[Bills R2]

I have a perfect ring & pinion in 3.54 if ya need 'em.

'64 R2 back on da road again
POCI,SCCA,SIMTA