As long as 1st gear & 2nd are not to far apart in ratio it seems to me the 3 spd is the way to go.That is the prblem with a glide,it only shifts once causing a huge RPM drop unless you have lots of HP & torque to pull high gear,then it does not matter.Case in point,a clutchless 5spd car will be faster than a cltchless 4spd in the same car because the eng. stays wound up tighter in the power band.bb466 got 3 years out of a c4 with only one breakage,& he races a lot & has about 600HP.Get a pan fill c4 they are the strongest.
The converter becomes even more critical when the gear ratios are a wider split, and even more critical with less horsepower and torque. The wrong camshaft + wrong converter will absolutely kill the setup, even if they're just a little bit wrong. With today's converters it's possible to set up a wide ratio glide so that the RPM drop between low and high gear might only be around 400 RPM. Which brings me to my own setup, stalls 6000, shift at 7000 and it falls back to 6400. If I had put a "tighter" converter in, the pullback could be as much as 1500 RPM-which would kill the ET and MPH. turbocharged setups require a weird converter. Needs to be tight enough to not blow through but not so tight that it won't develop boost until 300' out. They're tough to get right. Nitrous converters tend to be tight when on motor only. Naturally aspirated, whole different ballgame. With a glide, the going trend has been to get the stall speed up around 200-500 ABOVE peak torque RPM. 3 speed, I would assume would be similar-but I have more or less quit messing with C4's and C6's as generally there is no performance gain and solely a purist and driver preference application. And with the C4, a little more attention to them (maintenance). Why do pro stock cars run 5 speeds? Because their engines make power at a very narrow RPM band and those 5 speeds can keep it in that band all the way down track. Same basic reason that most newer cars are 7,8,9 speeds....because they can "clean up" the exhaust emissions in that narrow RPM band, making them eligible for credits, among other things. Outside that narrow RPM band they may be dirtier or louder (noise emissions). This is speaking of automatics only-and is one major reason that manual shift transmissions are becoming a thing of the past. Thank you, US Government..... And finally, I've said it a million times, but a converter is a lot more complicated than stall speed only.....
I have both a stock ratio C 4 and a Wide ratio, the Gear ratio in my wide ratio is 2.92 first gear 1.68 second and 1.00 high! I shift at 5500 my first shift with the wide ratio is 39 mph the second is 67 mph and I run through the traps at 114! with Stock ratio I shift at 46 mph second at 78 mph and 114 for high ! My Car runs 2 tenths quicker with the wide ratio and it is all on the launch! My 60 ft with the stock ratio is 1.80 and with the wide ratio it is 1.60 the launch is the same as if I had a 4.5 rear gear, My Rear gear ratio is 3.73!
I think the 2.75 & the 1.57 would work pretty well in my car when I get it running.With a 4.56 out back,1st gear equals a 7.71,a neck snapper that will be more than enough to get a 2800lb car including me off the line & 1.57 is`nt to bad of a drop for 2nd.With a 408 they tend to make the most torque around 4500 so a 5000 stall is all I need & with my cam I`ll shift around 6500.With 31 in. tall tires on the rear I`m going to have enough gear to get me off the line with them & that height will give me some speed on the other end.
how much would you want for it I am looking for another person I would have to tell them and then get back to you
I recently found out from a friend that if you use a whole pump set up from an E4OD it has a lower set of gears with it.
The E4OD is the big brute used behind 460(and also lesser engines), figures I've seen stated 2.71 1st... The 4R70W is the wide ratio automatic used in passenger and light trucks, has 2.84 first... I dunno what can and cannot be swapped to C4 from either...
That is right the E4OD is the Heavy transmission for ford trucks the planetary can be used in a C6 to give a lower first gear ratio, Drag racers have been doing this for years but size makes it a poor fit into a Maverick Like the C6 the E4OD is a power eater.
call Mike at virginia speed, I run his 292 low gear in my c4 going mid 10s and have over 200 passes on it. planning on going thru it this winter
