I would prefer to swap the entire carrier, as mine isn't broke so why 'fix' it, and changing back would be easy.Greater tire selection would be awesome.AJ, I wasn't even thinking TKO, my apologies I definitely should have posted the trans. It is an A-855.
Ratios are 2.64, 1.92, 1.40, 1.00, 0.70.
My understanding is the 15s with 255s would essentially lower my rear end gear ratio.
Yeah that 2.64 low gear was a deal-breaker for me. The A855box has almost identical ratios to the standard
A833(2.66-1.91-1.39-1.00) except of course for the added overdrive. Nothing wrong with that if you also convert the rear end to plus 20% over say 3.23s. That would be 3.91s.
That will get you a starter of 10.40/perfect; a second that will get you
60=5600, and a very nice 32@2990; and 65=2210 also very nice.. All math done with 27" tires. Where it counts; those numbers are very similar to the numbers I now run, and IMO, with a 223 to 230 cam, they are perfect,lol..
This 60mph=5600 likes a cam to peak at ~5400 so Ima thinking a
[email protected].
The cruiser gear will like a
[email protected]
First gear don't much care unless your cylinder pressure is in the basement.
So Ima thinking a
[email protected] cam is up the middle, peaking at around 5300. Good headwork will easily carry that to 5600.
A 230/237FTH on110cam cruising at 2210 will suck gas pretty bad. I'd close it up to 108.
A 223/230/110 cam can make great fuel economy@2210.
A 228/110 is in the middle somewhere, but for street, I would close it up some anyway. And with headers,I would ask for no more than a5* split on the intake to exhaust; so 228/233/107. I would make that a fastrate(42* ramps maximum) and install it at 105, for an Ica of 60*, This will give you enough extraction to not go broke filling it up on gas every few hours. At 900 or so ft elevation; this 60* Ica will work pretty good with 9.6 Scr or so. This would make an excellent street combo............. except for one thing; It will roast those 255s to smithereens in no time.
Of course if you have some other cam, then you might wish to run some other than 3.91 gears. I'm just suggesting the above as a good match.
Those 255/60-15s are about 27" tall,
about same as 295/50-15s, same as 275/55-15s, about same as 225/75-14s..
A common tire grouping for our A-bodies is 25.5 to 27, with 28s being about the tallest. From the tallest (28) to the smallest (80) is a 10% difference, equal to the difference from 3.23s to 3.55s, or 3.55s to 3.91s. So yeah you can play that tire-swapping-game if you don't mind mega-tirespin with the 80s, and no sideways traction at all; if the car starts to rotate on you, you will have only milliseconds to correct it, then around you go; forget skinny 80" tires. Forget 80s period.
For straightline work, the taller the better; 275/60-15s are at about the height limit of 28 inches. After that you will have to move the rear axle back or start cutting on the body. I ran that size at one time, and for straightline work it did pretty good. I only moved to the 295s (27 tall) to get the width I needed, to keep from spinning-out all the time.