Hi just wondering if i can build a
302 small block with a 283 crank that i have
plus a spare 71 350 eng out of a heavy half
ton truck ideas??...... thanks GTA

 

sure can if you get the crank welded up and then ground down, the journals are differant sizes. might be easier, better, and cheaper to buy a crank with a 3" stroke for a SBC.

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ICON Motorsports
1st & 3rd
MM Black Diamond 538 F&AM

 

Yes and no. Getting 302 cid does use a 4 inch bore of a 350 block with a 3 inch stroke from a 283.

The downside is that 283 cranks use 2.300" mains and 2.00" rods and a 350 block or any SBC block starting in 1968 uses 2.450" mains and 2.10" rods.

What this means is that the crank won't fit in the block. The mains are too small for the 350's bearing caps and you would have to use the smaller diameter 283 con rods.

A true 302 built in 68 and 69 used a large journal "steel" crankshaft. The ones built in 67 used a 283 small journal crank.

Since the chance of finding an original steel 302 large journal crank to fit into a 350 block are almost nill your best bet for building one is to buy an aftermarket crank. Don't forget, finding one means it's 33 years old and there's no telling what kind of condition it will be in.


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you could use a small journal 327 block and a 283 crank.. most of the 283 engines had steel cranks and are relativly easy to find... Kevin

 

you can use the crank from a L99. That is a 265 CID(4.3L v8) version of the LT1. Its not as strong as the old cranks. Its not steel. It is one piece rear main seal though.

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-Tas
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Or, if you still have the 283 block, bore it out, I believe the 283 will take .125, which brings you to 301.xx CI's, used to be the "first" 302 in the late '50's, early '60's.

 

The aftermarket makes spacer bearings to make up the difference between the crank and block...

 

i'd like you to tell me who makes them or who sells them because i've looked for quite a while and have never found them. i know in the 70s it was common for someone to buy and use the spacers or thicker bearings but i don't believe they're around any more.


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ICON Motorsports
1st & 3rd
MM Black Diamond 538 F&AM

[This message has been edited by ede (edited August 11, 2001).]

 

The small journal 327 block is the easiest way but good luck on finding off the shelf pistons that arent 11.0/1 By the way why would you want to do something to cut horsepower?

 

The only block spacers I've seen are for putting a 350 crank into a 400 block. That's not saying there are any out there but I've never seen any either.

You don't really cut HP but lose a lot of torque because of the short stroke. The 302 is a good road racing engine and could survive at 8000 rpm for a long time. At that high rpm you can produce a lot of HP.

[This message has been edited by Stephen 87 IROC (edited August 11, 2001).]

 

Not to start any arguments, but I've seen (and stood next to) 302s that make over 600HP. Granted, there isn't a lot of torque at the lower end, but HP=Torque X RPM/5250, so if geared and massaged correctly, the 302 can be a real punishment to most 350s as soon as they get near the 7,000 RPM region.

Have you ever have "trouble" with a 302 Ford? Same bore and stroke, dude. It's just that the Chevy has a stronger head, deck, and bottom end, and the potential for a lot better valve train than the Dorf 302 (or, 5.0, as you new guys call them - with a strong emphasis on the ZERO). I've also seen 348 Fords thatstarted life as a 302 and have improved the head flows, so be careful what you line up against.

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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

Hey, doesn't trick flow make a 302 crank milled for the SBC?

 

Would be kinda neat to see a 302 in a thirdgen since they did it to a fourthgen already.

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