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Discussion Starter #1
Just bought New Ford Sportsman 302 block to go with my 331 internals from my Factory HO block

Installing Eagle Forged 4340 Crank, Eagle Forged Rods, JE pistons
Planning to push this block to about 800 hp. My old HO block was making around 600hp at the motor with a main girdle and all the forged parts. I have questions

Can I use the same girdle from my factory HO block and put it on my Sportsman block?

Ford Catalog says block is machined and finished (ready for use)
Block needs to be bored 4.030 and notched. What else?

If my old block is bored 4.040 can I make it into a 308?

thanks alot
Forced331
 

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Although I'm sure it has been done, I personally would not be comfortable pushing a 302 Sportsman B50 block to 800 HP. Ford says 600 HP, and I think that's pretty realistic for something with decent longevity. To survive for a while at that level, you'll absolutely, positively have to keep it out of detonation at all times.

If you're going that extreme, you'd better have the best machining, blueprinting, and balancing that you can get. Get the block squared and aligned to the crank centerline. You'll probably want around a zero deck height to keep a tight quench clearance, especially with that kind of cylinder pressure. Check the mains to be sure they're straight; align hone if necessary.

I have all of the above, plus all forged components, and a Probe 5/8" thick billet Track Dominator main girdle in my N.A. 347 which should make ~450 FWHP. I figure that leaves me room for around 100 HP spray; and that's all the stress I'd care to put on my Sportsman block.

Steve A.
 

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I have heard that the main girdles cause distortion if you bolt them on without having the mains line honed with it on there. Has anyone done this and seen any issues with getting the bearing clearance to repeat consistently after removing and reinstalling the girdle?
 

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If the bottoms of the main caps are perfectly flat, aligned in the same plane, and the girdle is also flat, there should be no distortion created when tightening down the girdle on the main caps. It is the equivalent of putting a spacer under each of the bolt heads...shouldn't affect main clamping or bearing crush.

On the other hand, if there are "peaks and valleys" when the girdle is placed on the main caps, then distortion would obviously be possible. A good machinist should be able to fit the girdle to the caps, by grinding or milling the bottom of the main caps if/where necessary. With that done, if the main bores were in alignment before the girdle, they should remain the same after girdle installation.

Steve A.
 

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I've got a Probe 1/2" billet girdle on a stock 5.0 block that's sitting in my garage. Probe assured me that no alignhone was required. Well, when I took it in to be bored, they checked the mains alignment, and yes, it need a line hone. The machinist told me that he had never seen a girdle installed that didn't require a line hone. He said that it was caused by small differences in the height of the main cap bolt boss from one main cap to another.
 

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I installed Cantons girdle on my B50 block. It was a perfect match.
You will have to see how your gordle fits.

The B50 block can only be bored .030 over. The walls are too thin for anything more than that.

The block came finished but you will need the oil gallery plugs, oil filter thread thing, and tranny/timing cover dowels. I still had my block checked out.

David
 
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