I'm soon to start building a 383 with a target of 500bhp/500 ft/lbs, and from a fair bit of research I have come across several combinations that should do the trick.
I've got my donor block which is from a '90 GMC Vandura which from last night's investigations is a 2 bolt, non roller block... at least it has a 1 piece seal going for it.
Having bought the donor car, broken it, retained the V5 and trans for BIVA reasons (two major components from the donor and all that malarkee for age related plate and pre '93 emissions etc) I'm pretty committed to using this block, especially as it was low mileage, virginal an ran perfectly before I removed it.
So... a few questions if I may.....?
From my research it seams that the threshold for needing 4 bolt mains is circa 500 bhp to be safe, so I guess I'll need to get it machined for splayed 4 bolt caps??
Who in the UK is experienced and good quality for this type of machining work?
Also, my research also suggests that from about 450 bhp upwards, roller cams tend to be used, which is a problem, as I don't have a roller enabled block.
It seems as if a roller cam is good for about 20bhp gain on a like for like spec motor. Is there any way of equipping a non roller block with a roller cam, or any other suggestions of how I can make up the loss of power from having to use a flat tappet cam without just going for a crazy cam profile which will ruin flexibility?
My intended spec 'was' before I discovered it wasn't a roller block was...
383
ARF 195 heads
10.5 CR
Comp Cams Xtreme Energy (12-433-
Forged Eagle Rods
Forged Eagle Crank
KB pistons
Edlebrock Perf RPM manifold
Edlebrock Thunder series 850 Carb
MSD etc, etc.
Thoughts, comments and guidance appreciate. Ta.
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