i have stock 400m rods i just need pistons and a few other odds and ends. my question is what hp level will these rods handle? my cast rods in the car now are holding up to 400+ rwhp. will 400m rods hold more? these rods look a little bit more meaty than stock 351 rods.
thanks
jake
You could build a 393 for the money you will spend on a long rod 357. A 10% increase in displacement will do more than a slight decrease in friction. C5R 427s use 6" rods and 4" stroke for a 1.5 rod ratio. They gave up rod ratio for cubes. Modern pro stocks, which are likely the most advanced pushrod motors in the world, run around 1.7 rod ratios which is very close to a 351w. I doubt you would find any engine builders that will tell you rod ratio is more important than displacement.
you might want to polish the beams of the rods, and then have them shot peened for more strength. this will remove any stress risers that are left in the rods. and for the record, ford rods, untill the mod motor came along, are actually vacuum forged, not cast.
rbohm:shot peening the rods, i'll probably get that done before they go in. i guess never hurts to add a little strength.thanks
bnickel: the engine has afr 205's, a victor jr converted to f.i., and a comp cam xtreme fuel injection cam (236/248 579/579 114lsa) don't have any new numbers. old numbers were 360/400 rear wheels with small cam,smaller injectors and a different intake. i have heard the same thing about forced induction 5.0's making the same numbers on stock internals. i also heard the same thing about stock internal 5.8s good for around the same or higher. it all depends on the tune!
You could build a 393 for the money you will spend on a long rod 357. A 10% increase in displacement will do more than a slight decrease in friction. C5R 427s use 6" rods and 4" stroke for a 1.5 rod ratio. They gave up rod ratio for cubes. Modern pro stocks, which are likely the most advanced pushrod motors in the world, run around 1.7 rod ratios which is very close to a 351w. I doubt you would find any engine builders that will tell you rod ratio is more important than displacement.
oh yeah, i know that more cubes equals more power. the point of the engine i'm going to build eventually will be to maximize efficiency of the stock displacement windsor, not exactly to make the most power possible and still look stock. what i want is a windsor that when coupled to an AOD with a 3.25 rear gear in a 69 coupe (or possibly a 70 cougar if i have to sell the stang) will be capable of low 13's and able to get around 25 mpg or more, preferably more. i have gotten as much as 23 mpg with a stock windsor and fmx in the same car, so i know it's possible. and that engine was probably good for low 14's to high 13's.
the plan is to use a late model roller windsor block, the above metioned 400m rods, a mild duration but fairly aggressive lift roller cam, a good set of heads, right now i'm considering afr 165 competition ported heads to keep velocity up but still flow enough to feed a stock displacement windsor. it'll have as many internal coatings as i can afford. definitely it will have coated piston skirts, and piston and head combustion faces and coated bearings. i'd like to run a danny bee belt drive, but i may have to skip that since this will be a driver. most likley it will have a holley commander 950 pro-jection TBI system with the timing control function using a stock style tfi distributor or more than likely an MSD version. it's also going to have some kind of ignition system probably an msd or maybe a crane hi-6 still undecided. i've also got a few other tricks that i'm keeping under my belt for the time being but suffice it say one of them will dramatically improve low rpm flow and velocity into the combustion chamber.
you might want to polish the beams of the rods, and then have them shot peened for more strength. this will remove any stress risers that are left in the rods. and for the record, ford rods, untill the mod motor came along, are actually vacuum forged, not cast.
I've heard both opinions on polishing the rod beams, with him not planning to spin it that high, he's probably better off leaving them as is. Some of the guys over on the FE forum on Network54 say that polishing the beams ruins them, some say no.