[WANTED] Want to buy 7 1/4 sure grip

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Guido; by the time you add up converting your open7.25/3.23s to, 3.55s/SureGrip, money-wise, you would be well on your way to purchasing an 8.75, which has drop out centers.
Furthermore; from 3.55s to 3.23s is only a 10% change.
If you are looking for more off the line oomph, a much better idea is a higher stall TC (assuming she's an auto).

In your car, if a streeter, the 3.23s should give you a nice Second gear, hitting 60 at 4400 with 24.5" tires and 15% slip................... which would be peak power with a 2-bbl engine. But with 3.55s it would be 4840.
I suggest a 2800TC.
 
AJ/FormS said:
Guido; by the time you add up converting your open7.25/3.23s to, 3.55s/SureGrip, money-wise, you would be well on your way to purchasing an 8.75, which has drop out centers.
Furthermore; from 3.55s to 3.23s is only a 10% change.
If you are looking for more off the line oomph, a much better idea is a higher stall TC (assuming she's an auto).

In your car, if a streeter, the 3.23s should give you a nice Second gear, hitting 60 at 4400 with 24.5" tires and 15% slip................... which would be peak power with a 2-bbl engine. But with 3.55s it would be 4840.
I suggest a 2800TC.
Click to expand...
Agreed, except for the 8 3/4 rear. Nothing wrong with a 8 3/4 except price, there are other options, at a lower price point.
 
AJ/FormS said:
Guido; by the time you add up converting your open7.25/3.23s to, 3.55s/SureGrip, money-wise, you would be well on your way to purchasing an 8.75, which has drop out centers.
Furthermore; from 3.55s to 3.23s is only a 10% change.
If you are looking for more off the line oomph, a much better idea is a higher stall TC (assuming she's an auto).

In your car, if a streeter, the 3.23s should give you a nice Second gear, hitting 60 at 4400 with 24.5" tires and 15% slip................... which would be peak power with a 2-bbl engine. But with 3.55s it would be 4840.
I suggest a 2800TC.
Click to expand...

I have a 64 push button auto 273 now has new 27" Dia rear tires on new small bolt pattern 15" cragars. I don't know what gears i have now I expect stock 2.74 gears. I have a 2.93 extra set of ring and pinions. Its doggy now off the line I won't race it. Just want better acceleration and 7 1/4 suregrip bragging rights what gears should I use
 
Charlie is working with me at the moment, I'm new here how do I get to text rusty rat rod
 
About 2 weeks ago or their about.
Robs holding it till I can get to it.
I have another one from a 64.
I don't know what gears or condition honestly, but pm me I most likely will part with it.
 
guido said:
what gears should I use
Click to expand...
Use what you got, just put a 2800TC in it.
This is like slipping the clutch with a manual trans, up to where the power is . At 2800 your 273 will be making something like plus 50% more torque, than what it does at the stock stall. The 2800 will still accelerate your car at lower than 2800 rpm, just with a lil more slippage as you lay into it. It doesn't take much getting used to, and then it actually gets to be fun.
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Below is a generic image I grabbed off the Net. Don't try to reconcile the numbers to your engine. Just look at the power number percentage increase from 1800 to 2800. I'll guess from 100hp to 150hp=PLUS 50% ..
Now with a 10% increase in rear gear, the torque-multiplication is increased 10%. On this graph the torque at 1800 is ~270ftlbs. Adding 10% is 297, and converting back to horsepower at 1800 is~102.... versus ~92 on the graph; is an increase of 10hp which is plus ~11%.
What would you rather have: plus 11% or plus 50%
Your absolute numbers will be different, but the percentages will be close.
curve_47.jpg

Now, to answer your question; to gain the same percentage boost at Zero mph, with a rear gear boost, will require close to 50%, so say
1.5 x 2.76= ~4.10s
Ok then 4.1/2.76 = plus 49%, and 1.49 x 270 ftlbs converts to 138hp, compared to 92 is plus 50% Badaboom!
Therefore; on the start line, a 2800TC will equal the 4.10s in take-off performance.
However;with 27" tires, your first two gears will be;
the 4.10s will hit ~34@4800, and 60@5300; no passing gear at all. versus
the 2.76s will hit ~52@4800, and 60@3550; nice passing gear
Happy HotRodding.

Edit
you could split the torque-Multiplication between them, for a happy medium of say 3.23s with a 2400TC. This will get you say 25% more ftlbs at Zero mph, and still get you thru the gears quicker. The new speeds are; 43mph at the top of First, and 60=4150 in Second, giving you a bit of headroom for passing, say up to ~4800@69mph.
I really liked this 2800/3.23s combo when I ran it........ behind my 318LA in my 3600pound tank, Barracuda, (me in it)..
PS;
If you want to run those rpms, you better make sure your valve springs will support it.
Since you already have the 2.94s; I would throw those in with a 2400 to 2600 TC
 
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