Tom, Glad to hear you got settled in at the new place. Have had to care of some other things so the car has been sitting,hoping to get it finished shortly.
Thanks 300, real nice being in a cooler area, when it gets up 85-95 that is a real heat wave for Camarillo. The heat in Bakersfield is in full summer swing 100 - 110. Not missing it at all. Question, what type and stall converter do you run in your door car? Is it a Ford 300 motor? Are you going to run the same in the dragster?
Old28,never got to run the pinto but will be trying a 2,500 stall converter in the rail.Think it's just a local shops converter.
Going to move some of my questions over to my thread about the Ford 300" six and give bobw a rest. Hopefully flyer will shed some light on this piston question. In reading the treads on fordsix.com that the 390 ford V8 piston is a 4.050 bore, is that correct? The 352 ford V8 is a stock 4.000 bore, but you have to mill .050" off the piston top to have a -0- deck match, is this right. Do you have to take any off the block surface to make this work? Will .050" off the piston top remove all of the valve pockets? Stock piston CD is 1.767, 352 piston is 1.816, works out to .049 longer. Can stock 300 rods with ARP bolts be used with the 352 pistons? Can the 352 pistons be had as forged units? What is the max bore these 300" blocks can go with 10.5 CR and around 6500 rpm? Any and all information is "all good".
Old28, Yes, the 390 piston has a 4.050" bore. I prefer the 352 (4.00) size for future rebuild capability. You will have to cut .050" off the top of the 352 piston. Here are some photos of a set my bud made. He CNC'd the top, leaving a .050 "dome in the area of the combustion chamber, but you can see how much valve pocket would be left if milled flat. Aftermarket manufacturers have made forged 352 pistons in the past, but used ones are not plentiful. Yes, stock rods were used. I forgot if they were the smaller .912" pins or the larger .975 pin. I had an early 300 with a .060 oversize and it lived at 6500. But smaller would be better. One more caveat about using a set of used V8 pistons in an inliner: If the set originally had a pin offset to promote quieter running then using those pistons in a six will result in at least some (min. two) pistons will have the pin offset in the wrong direction vis-a-vis the bore axis, resulting in a very noisy engine.
To me, this type of conversation is what it`s all about. Many of us are getting a little long in the tooth and as far as I`m concerned it`s just as much fun working on and improving the performance of our cars as it is racing them. The car I`m going to build with a friend is something new for me as in motor wise and for him because he`s got some major brand loyalty issues. One question, has anyone used a c-4 or c-6 3 speed auto instead of the usual powerglide. I know the glide has less parasitic loss than most, but do you guys know how much hp is lost with a ford 3 speed auto.
FLYER - thanks for the information on the pistons. Did you have to mill the block to make a -0- deck? Are the tops of the 352 pistons ok with .050" milled off in a 10.5 CR / 6500 rpm motor setup? old sparks - Dan, I know that an old buddy of ours Dick M in southern ca is putting an Art Carr C-4 behind his 300 and I think one of the NW Vintage cars runs a C-4 or C-6. Lot of Ford bracket door cars run Art Carr c-4 & c-6 units. Cost a little more if you want a PG hooked to that 300. I am with you in it's more fun trying to make the parts that are out there work than ordering a set of custom pistons. I am just looking for an interesting combination that would make a reliable motor for a little less cash outlay.
Originally Posted by Beechkid This is info from an old Car Craft Mag publications: Horsepower loss Powerglide_____18 hp TH-350________36 hp TH-400________44 hp Ford_C-6______55-60 hp Ford_C-4______28 hp Ford_FMX______25 hp Chrysler_A904__25 hp Chrysler_727___45 hp Automatic Transmission Gear Ratio's GM : Powerglide...........1.76/1.82 1.000 TH-350................2.52 1.52 1.000 TH-400 (3L80)......2.482 1.482 1.000 Ford: C-4.....................2.46 1.46 1.00 C-6.....................2.46 1.46 1.00 AOD....................2.40 1.47 1.00 .67 AOD Wide.............2.84 1.55 1.00 .67 AODE/4R70W........2.84 1.55 1.00 .70 I remember those figures. Good info. But some readers may get the impression that spinning the transmission at ANY SPEED / LOAD condition will require that much power when, in fact, that was the maximum amount of power required at WOT, high speed. If you're just cruising down the highway at legal speeds your power draw will be on the order of a magnitude less, so as not to be such a great factor. I would be willing to wager that torque converter design / stall speed / size has a much greater effect on fuel consumption that the type of transmission used, especially in high gear (direct drive) where you are not putting any power through the planetaries.
TFF -- thanks for all the information on different trans setup and the piston. I would think that the HP loss in a built C-4 would be almost the same as a built PG. Any good cast pistons in the 352 size that would work in a low HP 300 motor in the 5000 - 5500 RPM range?
The C4 may come close to a PG but it has two sets of planetary gears vs one for the PG. Of course that gives it three speeds vs two. The PG would still win a power loss race for equivalently prepped trannnys. The design of the 352 piston pictured looks much stronger than a stock 300 piston to me.
TFF -- Do you think a good cast coated 352 piston could work in a low budget 300 with a 5800 max RPM? Are the aftermarket cast pistons solid enough to have .050" removed from the tops?
The Jalopy Journal
