Who is running 2.72 gears with their HEHE Tranny?

D

Duke Mk1a

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Who is running 2.72 gears with their HEH-E Tranny?

How does 1st gear feel? My wallet would sure love the lower RPMs in 4th.

I am running 3.07 currently and can spin the DOT-R Toyos at will in 1st and 2nd.

Engine has to come out in March to fix rear main leak.....might as well pull the rear axle too.
 
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I seem to get a little wheel hop with mine off the line unless I give it more gas--kind of wish I had a 5 speed for the better off the line but good freeway RPM's.
 
Duke Mk1a said:
How does 1st gear feel? My wallet would sure love the lower RPMs in 4th.

I am running 3.07 currently and can spin the DOT-R Toyos at will in 1st and 2nd.

Engine has to come out in March to fix rear main leak.....might as well pull the rear axle too.
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Duke.. even though your motor has monster torque i'm thinking that will make 1st very tall, you will be slipping the clutch a bit from stand still. You would be better switching to the 2.72 but installing the wide ratio box to keep it more driveable... then again.. can bite the $ train and buy the Tom Hall 5 speed setup... best if both worlds
 
michael-king said:
Duke.. even though your motor has monster torque i'm thinking that will make 1st very tall, you will be slipping the clutch a bit from stand still.
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I feel that the Sunbeam engineers felt a 2.88 was good match for the HEH-E even with only 160 HP and stock clutch. The 2.72 is not that much of a change from that combining with over twice the HP, Centerforce clutch, heavy duty throwout bearing and beefier clutch arm...........I should be OK.

5 speed is in my 5 year plan ;)
 
Duke Mk1a said:
I feel that the Sunbeam engineers felt a 2.88 was good match for the HEH-E even with only 160 HP and stock clutch.
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Well in the MKII with 40hp more than the MKI they switched to the wide ratio with the 2.88.... so they must have thought it was an improvement... better acceleration and same top speed/rpm cruise.

It would be interesting to know why they had the CR box intially.. marketing reasons, what was offered.. either way.. i think i'd like to have the wide ratio set in mine C/R is great on a race track.. not so great on the road or at the strip.
 
Hey Duke

I did some calcs for you using Bob Hokanson's trans calculator ( ya gotta get a copy... it's on Tigers United site ) and used your tire height of 22.68" ( 1" shorter than mine )

For cruising... you should now be at 3200 rpm @ 70 mph

Using the 2.72 gears you will be at 2800 rpm @ 69 mph

At the bottom end ( 1st gear ) ... 5000 rpm...

With your trans and 3.07... 47 mph ... with wide ratio trans ... 40 mph

With your trans and 2.72... 53 mph ... with wide ratio trans ... 43 mph

So... looks like you would do a little better on the highway and maybe just a tad less clutch slippage at the drags...

edit: Just another thought...with your existing gears you are about 107 mph @ 6k rpm in 3rd, but the 2.72's would give you 121 mph ... might be able to leg it out through the traps without that last shift :D

David Kee sells the parts to convert your trans for $550 ... Hmmm... Christmas is just around the corner... ;)

BTW... I talked to a friend ( the one with the 347 Tiger project ) about your fuel pressure problems and he had a VERY similar thing going on with his 351 Cobra replica...
Would you believe the culprit was the lack of venting at the tank...??!!
He said he'd put money on it that if you had someone 'pop' the filler cap (and close it again) just before you made a pass that it would be O.K. ... lol

Jim
B382000446
 
2.72 GEARS

Since you are using a Quick time bellhousing with narrow and wide trans mount bolt pattern, you might consider Keisler Enginering Modified T-45 5 speed. The shifter location supposedly is within 1/2 an inch of the stock location (Tigers /Alpine East forum post). At $2600 it is a lot less than Tom Hall's T-5 conversion kit. They also have options on transmission gear ratios. You get to not mess with changing rear gear ratios.
 
Thank you all for the great points you have brought up. Love this board as it has so much great knowledge on it.

You guys are also great at spending my money. :rolleyes:
 
66TigerMK1A said:
BTW... I talked to a friend ( the one with the 347 Tiger project ) about your fuel pressure problems and he had a VERY similar thing going on with his 351 Cobra replica...
Would you believe the culprit was the lack of venting at the tank...??!!
He said he'd put money on it that if you had someone 'pop' the filler cap (and close it again) just before you made a pass that it would be O.K. ... lol
Click to expand...

Jim - that crossed my mind at the strip and ran once with cap popped. Had the fuel issue on that run too. If the car is cool, no issue. A tank vent issue would be there regardless of temp.
 
Ultra Wide Ratio Toploader with 2.72 Rearend Gears

I admit, I am the culprit who sold Duke the 2.72 rearend gears. I kind of talked him into it, so you can blame me.

I converted my close ratio toploader to a wide ratio, but installed David Kee's 2.90 first gear in place of the factory 2.78 first gear. I am running stock 2.88 rearend gears and my first gear launch is outstanding. Like Duke, I am also going to change my 2.88 rearend to 2.72s. This will drop my first gear to an equivalent 2.74, almost identical to the factory 2.78, but will give me a 6% overdrive in fourth compared to the 2.88s.

The tranny conversion was only $200. I bought the wide ratio gears for $450 and sold the close ratio gears for $250. The 2.72 gears were less than $100. So for less than $350 I'll get a wide ratio tranny and a 6% overdrive.

Gary
 
Labor?

Malibu,

You leave at least three things out of the calculation?

Labor to install the gear in transmission and diff.

Labor to R&R (engine and) transmission and diff.

The odds? that it all goes smoothly and works the first time? (hint less than 100%)

Merry Christmas and hope to see you on the Toy Drive Saturday.

Rick
 
Labor?

Rick,

I guess I'm just lucky. I do all the labor on my Tiger myself. I have converted 5 of the close ratio transmissions to the wide ratio setup with the 2.90 first gear. The last one I did (for Craig), the owner uses taller 15" tires. The car comes off the line easily, no revving of the engine and slipping the clutch, and with the taller tires and 2.88s 4th gear cruise is nice.

I wish I would have known about the 2.72 gears when I installed my positraction and I could have done that at the same time.

Gary
 
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