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Anyone have any information on stroking a Pontiac 350 with a crankshaft from a 428?
Or info of what needs to be done to 400 heads when bolting onto a 350?
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The first response would be: "Why?" Pistons: Custom only. Decent 350 pisonts are already hard to come by. You'd need to have a set made with a CD .125" shorter. Crank: Grind the mains down to 3". That might upset someone who has a good 428 block and is looking for a good crank. Block: Relieve the block where the 428 crank (probably) hits it Or info of what needs to be done to 400 heads when bolting onto a 350? You need head bolts, assembly lube and a torque wrench to bolt 400 heads onto a 350. Actually, that's not entirely true. You done NEED a torque wrench, it's just a really good idea.
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Butcher a chevy, not a pontiac.
-Jeff
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Anyone have any information on stroking a Pontiac 350 with a crankshaft from a 428? What does stroking a engine mean?
Engine Test Stand Playlist: https://www.youtube.com/playlist?list=PLwoxyUwptUcdqEb-o2ArqyiUaHW0G_C88restoring my 1968 Firebird 400 HO convertible (Firedawg) 1965 Pontiac Catalina Safari Wagon 389 TriPower (Catwagon) 1999 JD AWS LX Lawn tractor 17hp (my daily driver) 2006 Sequoia 2017 Murano (wife's car) 202? Electric car 203? 68 Firebird /w electric engine 2007 Bayliner 175 runabout /w 3.0L Mercuiser__________________________________________________________
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Anyone have any information on stroking a Pontiac 350 with a crankshaft from a 428? What does stroking a engine mean? You use your right hand, touch the engine and slowly pat it all over the valve covers.....LOL sorry ,couldnt resist... 
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The first response would be: "Why?" Pistons: Custom only. Decent 350 pisonts are already hard to come by. You'd need to have a set made with a CD .125" shorter. Crank: Grind the mains down to 3". That might upset someone who has a good 428 block and is looking for a good crank. What's a tork rench? Block: Relieve the block where the 428 crank (probably) hits it Or info of what needs to be done to 400 heads when bolting onto a 350? You need head bolts, assembly lube and a torque wrench to bolt 400 heads onto a 350. Actually, that's not entirely true. You done NEED a torque wrench, it's just a really good idea.
1968 Firebird 428 4 speed coupe  2011 Camaro 1LT 1988 Corvette roadster 1975 Chevelle Malibu Classic 1984 Harley FLH Shovelhead 2001 Harley Ultra Classic
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Anyone have any information on stroking a Pontiac 350 with a crankshaft from a 428? What does stroking a engine mean? Increasing the stroke of an engine by using a different crankshaft or modifying the stock crank.
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I figured it was giving your crank a hand job!
Engine Test Stand Playlist: https://www.youtube.com/playlist?list=PLwoxyUwptUcdqEb-o2ArqyiUaHW0G_C88restoring my 1968 Firebird 400 HO convertible (Firedawg) 1965 Pontiac Catalina Safari Wagon 389 TriPower (Catwagon) 1999 JD AWS LX Lawn tractor 17hp (my daily driver) 2006 Sequoia 2017 Murano (wife's car) 202? Electric car 203? 68 Firebird /w electric engine 2007 Bayliner 175 runabout /w 3.0L Mercuiser__________________________________________________________
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Butcher a chevy, not a pontiac. I'd rather see someone stroke a Pontiac, then toss it in a scrap pile like the fate of many 350 BOPs. Or even worse, toss it in a scrap pile and build a Chevy! I say, if he's not happy with it, stoke it like a teenager!
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Joined: Dec 2007
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Thanks Mike, I appreciate the links, informative and I like the Tomahawk crankshaft. I was wondering if I would have to cut reliefs in the bores for the larger valve sizes and also unshroud the valves.
Bjorn, even tho its at my expense, laughed pretty good on that one, too funny! Told a couple friends and they chuckled pretty good as well.
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The small bore of the 350 often requires relief cuts just to clear the bore, let alone unshroud the valves. This depends on the camshaft, amount of overbore, and valve sizes. http://www.carcraft.com/techarticles/672hp_pontiac_350s/photo_05.htmlIf your 400 heads use the 1.66 valve, this would be less troublesome (of course still check clearance) and still provide good flow with some port work.
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Although I am a fan of a stroked 350, it's not nessesary to have a good street engine.
Before I'd do that I'd consider boring it .060 over and just adding some KRE 290 cfm heads built with 2.07 intake and 1.66 exhaust valves, machined to 68-70 cc's, zero deck the block and install a good cam, intake and ignition.
.060 over pistons are common and you'll be around 9.75:1 with the aluminum heads, quite a good little 365 cu in street engine you'd have there.
Wanting a Custom fit in an off the rack world. I don't have time for a job, I just need the money. 
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Hey Mike/HO428, where are you guys located in SC? I am in Summerville/N Charleston and have parts to sale/trade, send me your phone numbers and lets chat.
Dan
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