reversing pistons November 29, 2007, 06:17:50 PM so my friend goes to Nashville Auto/Diesel College and he said his teacher told him that if you reverse your pistons in a ford 302 it'll give you roughly 40 extra ft/lbs of torque due to pin offset. now, i've never heard of such a thing, but he claims to have built many ford 302's this way and reliability and drivability were never comprimised. the only engine he knows of that this works on is the sbf 302, no chevy's, no mopars. is this possible?on a side note(its not worth starting a new thread over)- is the 91 cougar HO's the same bottom end and valve releifed pistons as the mustangs? i assume it is Quote Selected
reversing pistons Reply #1 – November 29, 2007, 06:48:28 PM Quote from: grutinator;190211so my friend goes to Nashville Auto/Diesel College and he said his teacher told him that if you reverse your pistons in a ford 302 it'll give you roughly 40 extra ft/lbs of torque due to pin offset. now, i've never heard of such a thing, but he claims to have built many ford 302's this way and reliability and drivability were never comprimised. the only engine he knows of that this works on is the sbf 302, no chevy's, no mopars. is this possible?on a side note(its not worth starting a new thread over)- is the 91 cougar HO's the same bottom end and valve releifed pistons as the mustangs? i assume it isNever heard of the first, I'd say that's a big no.The HO's are the same. Quote Selected
reversing pistons Reply #2 – November 29, 2007, 07:33:15 PM yes the HO is the same as the stang one. That is actually the motor I pulled from my '91 Cougar and threw into my T-bird. Quote Selected
reversing pistons Reply #3 – November 29, 2007, 08:27:37 PM Ive seen several put together with the pistons in backwards my current motor was like that When i freshened it up i put them back right with absolutley no gain.Just an old rodders myth. Quote Selected
reversing pistons Reply #4 – November 29, 2007, 11:46:54 PM Yeah, gain would be minimal at best - I think I remember some engine expert claim 5 ft-lb or so (in the bad-old days of the Corral) Quote Selected
reversing pistons Reply #5 – November 29, 2007, 11:58:52 PM http://www.mustangandfords.com/techarticles/28898_400_hp_302_small_block/index.htmlfor your reversing the 302 pistons info needs. also reversing them makes them more noisey. Quote Selected
reversing pistons Reply #6 – November 30, 2007, 12:08:41 AM Wow, he claims 15-30 HP (of course that's on a 400HP engine)! Hey, that's the Joe Sherman who posts on the Corral and HC50 - hmmmmm... Quote Selected
reversing pistons Reply #7 – November 30, 2007, 12:20:55 AM QuoteHow about 400 hp—with ported stock heads, a cam with only 280 degrees of advertised duration, and one four-barrel carb? Even though they mill the block and spin it to 6500 RPM Are they using the same Dyno Car Craft uses?QuoteThe pinholes on Federal-Mogul and other replacement pistons are offset 0.060 inch from center to maintain quiet operation in stock applications. Normally the piston is installed with the notch facing forward (the pin and rod are offset toward the front). Installing the piston backward (with the pin and rod offset toward the rear) reduces rod angularity; the engine behaves as if it has a 0.300-inch-longer rod.Stockers are centered, right? It's been awhile.....and shouldn't it be an .030" bigger rod and not .300"? Quote Selected
reversing pistons Reply #8 – November 30, 2007, 07:28:21 AM according to his teacher stocks are offset too (if i understood him correctly). does this sound worth it? i very much considering rebuiling the bottom end so i can get away with a bigger then HO cam. i dont want to sacrifice reliability on the bottom end cus its gonna be a big anough pain to do once, let alone twice. Quote Selected
reversing pistons Reply #9 – November 30, 2007, 12:25:59 PM If you're going to rebuild the bottom end ayways just put in notched pistons Plus if you ever want to run nitrous you need forged pistons anyways.............:burnout: Quote Selected
reversing pistons Reply #10 – November 30, 2007, 12:37:04 PM thats what i mean, i leaning towards putting in notched pistons for extra clearance. arent aftermarket 302 pistons soppose to go in one way also? i would think the power results of flipping them would be the same. Quote Selected
reversing pistons Reply #11 – November 30, 2007, 12:41:44 PM Quote from: Cougar5.0;190279Wow, he claims 15-30 HP (of course that's on a 400HP engine)! Hey, that's the Joe Sherman who posts on the Corral and HC50 - hmmmmm...but what he doesnt talk about is the accelerated bore wear do to the piston/rod angle Quote Selected
reversing pistons Reply #12 – November 30, 2007, 12:43:44 PM Quote from: grutinator;190377thats what i mean, i leaning towards putting in notched pistons for extra clearance. arent aftermarket 302 pistons soppose to go in one way also? i would think the power results of flipping them would be the same.Yep they only go in one way. If I were you I wouldn't filp them for durrabilities sake. Flipping them might wear the engine out faster. I'm not sure if it would but I'd rather have a reliable engine. If I were you I'd find pistons that were flat tops with the valve reliefs (no dish) only on one side. It will boost your compression ratio and in turn increase power :D Quote Selected
reversing pistons Reply #13 – November 30, 2007, 12:44:35 PM Quote from: SLEEPER T-BIRD 87;190378but what he doesnt talk about is the accelerated bore wear do to the piston/rod angle:hick: You type faster than I do :hick: Quote Selected
reversing pistons Reply #14 – November 30, 2007, 12:48:01 PM groovy, i'll just get some aftermarkets and put em in like regular. flat tops with valve reliefs? this is starting to get into high compression. idk what stock chamber size is, but these heads have a 60 cc combustion chamber. how much compression can you usually run and get away with 93 octane? Quote Selected
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