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Old 08-07-2004, 06:02 PM
Super Streeter Super Streeter is offline
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There is limited swapability between the 8100 and most other bigblocks.The shortblock is a gen 6 type lowdeck with a 4.25" bore and 4.375" crank and stock length heavy duty rods.The crank is nodular iron with winged counterweights and is a good performance piece.I assembled a 555 using the crank from a 8100 vortec in a later 502 block{.030" over} and with lightweight pistons and steel 4.385" rods it lives fine making 850 hp at 7000rpm.We had some of the prototype stuff when it first came out and GM's intentions were to build a 496 inch shortblock that used standard bigblock valve angles and valvetrain components but had symetrical port prostock style heads ib it.The early version that I worked on had a 10 bolt head pattern like a ford motor but it used massive 5/8" studs.The intake used 4 bolt per side composite plastic intake.The heads flow very well and with a little bowl blending and some 2.25" intake valves they will outflow even the best aftermarket standard bigblock heads,and the cross section is small enough to make it all very streetable.Like I saud,the heads are very prostock like.I never worked with an entire production engine,but I know that the production piece uses a standard bigblock head bolt pattern and gen 6 water passages,and will use at leas regular mark 4 rocker arms if the studs are correct.It would be a great performance piece,and when I first got it I was working on building a combination to run my rae car in a class that requires production part number car or truck casting engine blocks and heads,with displacemnt limited to whatever you could stuf in a stock block,and since the original prototype was a siamsed wall casting,I was looking into it as the ultimate loophole combination once the engine went into production.The rulemakers required carbs and a regular distributor and sheet metal intakes or distributorless coversions were illegal,so the engine lost it's potential.All in all,if you dont mind working with the efi,the longblock has lots of potential for a drag race or stret rod buildup.Good luck.
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