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Author Topic:   Rod lengths
Wheels47
Member
posted September 17, 2002 06:21 PM
hey wheels....302's use a 5.09" rod. here's a trick little set up that will wake up a 302.

use the 289 rod with the 302 crankshaft, it's 5.155" long. shave the flat top pistons, usually under .050", to get zero deck height. you'll have to re-notch the piston for valve clearance. i've actually run these engines with the piston as much as .010" out of the hole. if you're on a cast piston budget, use the badgers or sterlings. i've used both and there's plenty of material for the machine work. i used to use the old ford "lemans" solid cam with '65 289 heads. i think the new gt-40 p heads will work well too. have it balanced. all this sounds like a lot of trouble but it's well worth it. it's a screamer. you'll be 75lbs. lighter on the nose than a small chevy and that sucker will rev to the moon.

the tech guys will never figure it out if you have a "no-mismatched cranks and rods" rule, even if they tear it down. i've used this combo in factory stock to outrun 400 chevys. had 'em scratchin' their heads.

forgot to add that you want to use the post '81 5.0 crankshaft. it's a lot lighter than the early ones.

[This message has been edited by outlawstock17 (edited September 17, 2002).]

ford5
Member
posted September 18, 2002 04:56 AM
the early 255 fords used a lighter crank yet, it only weighs 34 lbs i know a guy here who is using them and winning in the t-mod class, where all competetors have to run 302 ford, or 305 chevy, or 318 mopar. it is a very practical starter class for young guys and guys with out alot of money.


outlawstock17
Member
posted September 18, 2002 05:49 AM
thats good stuff ford5. the 255 has a 3" stroke too, right? how much does the 5.0 crank weigh? the only one i've got is still in the shortblock.

that t-mod class sounds perfect for a 302 ford. big weight advantage. how do they manage without all the bowtie boys squawkin'?

ford5
Member
posted September 18, 2002 05:00 PM
pre 1980 crank 40 lbs. 81up 36lbs and ya they do squak alot, lol


Wheels47
Member
posted September 22, 2002 08:41 AM
4ord, you have to use the 50 oz. balancer for all the post '81 302's or the 255. its only 22 oz. heavier than the old style balancer(1.4 lbs) so there is still a weight advantage. you could also use the 5.4" stroker rod with a custom piston. i used to know a guy that used an off the shelf small block chevy piston in his 289 rodded 302. i can't recall what chevy piston he used, but according to my calculations it would have to be about a 1.54 pin height and a 4" bore. the stock ford rods can be safely honed to the chevy .927 pin.

turning the crank down to chevy journals is no problem. it's alread 2.123, so .023 undersize and you're there. i'm not sure about the width of the chevy rod journal though. according to my calculations, an 8.20" deck block with the 5.565" chevy rod and 3.0" stroke crank, you'd need a piston with 1.135" pin height. sounds like a lot of trouble but in a 302 limited class, i think it would be awesome.

ford5
Member
posted September 23, 2002 05:57 AM
do not use chevy piston in ford 302 application, the valve reliefs are NOT in the correct places, you will bend a valve very easy


outlawstock17
Member
posted September 23, 2002 06:06 AM
the guy i mentioned that did the chevy piston/ford engine thing was kent canady. he worked at carbone racing engines and built a lot of 410 outlaw engines for WoO and really knew his stuff. i don't know all the details of his set up. if the valve notches were a problem, he could have re-notched them.

on another note, i use a 10 degree head on my ford and it doesn't need any valve notches up to .650 lift. i could use a honda piston if it were a 4" bore and i had the rods to fit it.

4ord
Member
posted September 23, 2002 11:03 AM
thanks 4ord, those are some pretty stout numbers for a 317 CI engine with a stock heads and that little hyd. roller. big 'ol flat torque curve too. i'm impressed.


Wheels47
Member
posted September 23, 2002 08:45 PM
excellent info from my original post. Lots of things to look up and study. Thanks for all the responses.

4ord--I don't have those numbers here with me but may pm you with them if I can remember to right them down when I'm at the shop.

Been kinda busy looking for a 3 speed trans--we busted our case last saturday night and just found the crack in the top of it and when we pulled it, a broken corner also was broken off..ouch!!!!

Love this racing-plus my son can drive the heck outta it now( if we can just hold her together)

Wheels

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