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studee64
03-28-2007, 03:48 PM
Can anyone advise me of the performance to expect with a 4:09 TT and a Powershift Avanti transmission...how good a launch, top speed, rpm at 70 mph...etc..

Thanks

Barry

Barry Leppan
Burlington, Ont. Canada
64 Daytona HT 5-spd
64 GT Hawk R-1/AC/Powershift

Magnum
03-28-2007, 04:58 PM
Barry,

What size tires will you be running?

JDP
03-28-2007, 05:16 PM
Once owned a Avanti equipped like that, very quick around town, but about 4000 RPM at 75 MPH, top speed, maybe 110 or so.

64 Commander 2 dr.
64 GT Hawk R2 clone
64 Daytona HT
63 R2 4 speed GT Hawk
63 Avanti R1
63 Daytona convert
63 Lark 2 door
63 Lark 2 door #2
62 Lark 2 door
60 Lark HT
60 Hawk
59 3E truck
52 Starliner
51 Commander

1956 Hawk
03-28-2007, 06:13 PM
I have 3.92s in my R2 4-speed Hawk. The Powershift actually has a lower 1st gear than the 4-speed, so it should be very quick off the line. With 27" tall tires I am turning 3500rpm at 70mph. With this setup my car will do just under 120mph at 6000rpm.
What are your plans for this car? I assume you are talking about your 64 R1.
David

Dick Steinkamp
03-28-2007, 06:41 PM
You can calculate it here...

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



http://thenobot.org/images/s2d/s2d_01.jpg

studee64
03-28-2007, 09:06 PM
Hi Magnum

This is for my 64 GT, have a set of 215/75R/15 Broadway Classics...Goodyear I think..

tks

Barry

Barry Leppan
Burlington, Ont. Canada
64 Daytona HT 5-spd
64 GT Hawk R-1/AC/Powershift

studee64
03-28-2007, 09:24 PM
Thanks for the formula Dick, a really neet tool...,

The car is for 'everyday' use, city and highway,.but still want to have some zip to it..

Bought it last summer and came with a T-10 transplant and the 4:09, and now has the powershift in it...

Was trying to determine if I can leave the 4:09 without 'any issues' or need to go 3:31 or 3:54 range..

tks

Barry



Barry Leppan
Burlington, Ont. Canada
64 Daytona HT 5-spd
64 GT Hawk R-1/AC/Powershift

Dick Steinkamp
03-28-2007, 09:37 PM
Barry,
For the calculator, your transmission ratios are 2.40, 1.47, and 1.00

ALL cars are a compromise. With the 4.09's your car will win most stop light grand prix's :D. It will FEEL quite quick. OTOH, it won't be the best long distance highway cruiser...not terrible, but certainly noisier and less economical than 3.31's or 3.54's.

If I were you, I'd drive it and see if I could live with it. If you actually plan to use the car "every day", 4.09's may not be for you. If you plan to drive 2-3000 miles a year with only an occasional long trip they would probably be fine.

I'm in the process of converting my 3.54's to 4.27's. I had 30,000 miles of fun cruising in this car...time for a change [8D]

http://thenobot.org/images/s2d/s2d_01.jpg

studee64
03-28-2007, 09:51 PM
Hi Dick

Thanks for the ratios...I was having a little trouble understanding the calculator..

I like your idea of trying it for a while and go from there...for some reason I think 3:54 or 3:73 is the best compromise...

Barry

Barry Leppan
Burlington, Ont. Canada
64 Daytona HT 5-spd
64 GT Hawk R-1/AC/Powershift

Dick Steinkamp
03-28-2007, 10:19 PM
Here's a chart for you...RPM's at 70 MPH with your 215/75/15's

4.27 3,600 RPM
4.09 3,500
3.73 3,200
3.54 3,000
3.31 2,800

The 500 RPM diff between the 3.54's and the 4.09's is going to be noticeable, but not a night and day difference.

Even with the 4.09's, at 6,000 RPM's you will be doing 120 MPH. How fast do you really want to go ;)?

http://thenobot.org/images/s2d/s2d_01.jpg

studebaker-R2-4-me
03-28-2007, 10:20 PM
Barry,

Let's see how these 4.09's react. My 3.31's were pretty peppy with my powershift and Modified 289 with R1 cam and Heads. I could easily chirp the tires with every shift. I found that I always used the powershift but then I like the performance. I think you would be better off driving both my car and your car right after one another to judge the performance and then make your decision of which gear ratio your looking for. I think the performance of our engines will be very similar. With your 4.09's You may want to use the power shift in first gear to dart the hawk out on a green light when your beside a punk in a rice burner with the big muffler. On the other hand Carol may well be happy and want to stay in drive. The powershift in drive starts out in 2 gear anyway so she will get plenty of ratio with the 4.09's in drive. As we chatted the other day I may be looking for another Dana 44 to swap out from time to time depending on my mood or when I go racing. With my new R2 under the hood I might not want any more than the 3.31's for daily driving but your 4.09's would make my car roar off the line. I know you have been eyeballing my 3.31's just as I too have been eyeballing your 4.09's. Those 4.09's would be an asset to me when I take my hawk to the PSMCDR next year. You might find you really like them too after driving my car and just keep them.

Allen

Karl
03-29-2007, 01:04 AM
Ran 4.09s in the Twin for years.It would run 114 out the back door in the 1/4. A good gear to race with. But if you do any amount of freeway driving. You won't like them.:(I put in a set of 3.73's. It did take a little snap out of low gear.[B)]But it made the car a lot nicer to drive all around. With and auto the 3.54 would work pretty good.Just in! Gear Vendor is making a O/D that will bolt up to the T10.:D They are sending me some templates to check the clearence in the frame. The down side is it $2600.00 :(

63 Twin Supercharged Avanti
64 Avanti R3w/NOS
88LSC Avanti 350 Supercharged w/NOS

John Kirchhoff
03-29-2007, 08:59 AM
Barry, I can email you a spreadsheet that you can enter your tire size and axle ratio and it'll show you the engine rpm's with whatever type of transmission you have (Ford or DG auto, Stude OD, etc). I have one for Excel and one for Works. Easy to use and easy to compare side by side the result of different tire sizes and ratios. Let me know if it'll help.

studee64
03-29-2007, 09:33 AM
Hi John

Thanks for the offer...Dick gave me a web site for a calculator which sounds similar, however would appreciate it if you could email me the Excel version..

studee64@cogeco.ca

Thanks

Barry

Barry Leppan
Burlington, Ont. Canada
64 Daytona HT 5-spd
64 GT Hawk R-1/AC/Powershift

showbizkid
03-29-2007, 05:29 PM
This discussion kind of begs a question: What are the redlines for the various Stude engines? I can't find that spec in the shop manual.

And why does the manual list horsepower for the V-8s at 40.6 across the board?



[img=left]http://members.cox.net/clarknovak/lark.gif[/img=left]

Clark in San Diego
'63 F2/Lark Standard
http://studeblogger.blogspot.com

Mike Van Veghten
03-29-2007, 05:42 PM
For what it may be worth...

I drive my stock (?) 259 Lark in the 3400 to 3800 rpm the better part of 160 miles (one way, four trips) at a crack. Twice a year.

That said...it does take its tole.

Exhaust valve seats, all valve springs (exhaust gets the worst of it).
If the bearing clearances are good, no bearing damage should occure.

OEM rods, pistons and pins if assembled correctly...should fair fine at that rpm.

BUT..........will your ears and wallet?

I put a set of 4.88's in my 56 Chevy (my only car!), with tall tires, lotsa years ago....
I "voluntarily"....was driving 55mph on the freeway long...before the 55mph law originally went into effect !!!

If it's "not" an everyday driver...and you don't go on long trips...you should be fine.
My Conestoga will have similar gears out back (if!) when I get my 299 Stude engine done.

Mike

StudeRich
03-29-2007, 07:52 PM
I don't get it Mike, why would you drive 1280 miles a year at 3800 RPM?
That's gotta be a tanker truck of gas and a lot of wear and noise! [:0] Wouldn't it be prudent (and cheaper) to just install a 3.31? That must be a 4.56 ratio at 70/80 MPH! A 259 TRUCK might make sense, at least you could haul something! :)


quote:Originally posted by Mike Van Veghten

For what it may be worth...
I drive my stock (?) 259 Lark in the 3400 to 3800 rpm the better part of 160 miles (one way, four trips) at a crack. Twice a year.

StudeRich
Studebakers Northwest
Ferndale, WA

showbizkid
03-29-2007, 08:31 PM
So now, according to the calculator Dick posted, my 259/FOM with 3.31 rear and 225/70R15 tires will top out around 86 MPH at 3500 RPM. Does that sound right?


[img=left]http://members.cox.net/clarknovak/lark.gif[/img=left]

Clark in San Diego
'63 F2/Lark Standard
http://studeblogger.blogspot.com

StudeRich
03-30-2007, 01:29 AM
I guess it depends on what you mean by "top out"? I always thought that meant the max it could do? But I know it will wind to 5500 and well over 100 MPH!

StudeRich
Studebakers Northwest
Ferndale, WA

John Kirchhoff
03-30-2007, 07:50 AM
Clark, according to my calculations, your Lark's engine should be turning in the neighborhood of 3,650 rpm at 86 mph with your tires and gearing setup (or 83mph@3500rpm). It appears whoever conceived the calculator Dick posted has forgotten to include slippage with a non-lock up torque converter. While the % slippage varies according to load, speed, etc, it never gets down to 0% unless it's of the lock up variety. Maybe the person who designed that calculator was a youngster (compared to most of us) and figured all automatics lock up.

According to my calculations, a manual or DG tranny would be turning around 3,470rpm with your setup which jives with the other calculator. The rpm figures are approximate because I've measured enough tires to know that not all tires are created equal in height and width even though the numbers on the side are the same. And it's not always the cheap tires that are smaller. Right now I have a 245X75X16 Dunlop on my truck that measures 29 inches in diameter when mounted and inflated. It's too darned short and I'm replacing it with a Goodyear of the same posted size that measures slightly over 30 inches in diameter. In your case, a tire one inch taller would reduce your rpms by 100, so that's why I say the numbers are approximate. On my calculator, you can take your actual tire measurement and adjust the aspect ratio up or down until you get the tire's actual diameter for a more accurate figure. However (there always seems to be one of those in my posts, right?), any old style tires that are not belted will grow taller as their rotation speed increases and will reduce the engine rpms. If you've ever watched the big fat tires on the back of a rail at the dragstrip grow tall and skinny when the driver pours the coal to it, you get the idea.

John Kirchhoff
03-30-2007, 08:19 AM
The 40.6 horsepower is taxable horsepower. In the good old days, when you bought a vehicle, your were taxed based upon the engine horsepower. The method of deriving the engine's taxable horsepower was a formula using the number of cylinders and cylinder bore in inches. For some unknown reason, the stroke wasn't included. Because of that wierd formula, the guys buying a car with a short stroke, large bore 250ci V8 payed more tax than someone buying a long stroke, narrow bore 250ci 6 cylinder. Most old titles will have the hp figure on there and Missouri still included that useless information on our titles even in recent years when we payed sales tax based upon the selling price. I don't know if they still do or not because I can't afford the price of a new car just to find out!

Mike Van Veghten
03-30-2007, 09:16 AM
StudeRich wrote -

quote:I don't get it Mike, why would you drive 1280 miles a year at 3800 RPM?

Well..
1. Don't want to be on the road "all" day.
2. For the most part, keeping up with the rest of the traffic.
3. It gets really boring driving at 65mph for over two hours.
4. Going to the drag races, don't want to miss anything!!!
5. Cause...

And no...tuned right, the milage isn't that much worse than doing the same trip at 70mph.

The rest of the year...all the car does is putt around town!!
Like a famous comedian once said..."Gotta burn it out once in a while, gotta get all the gunk out"!

Mike