is it always needed or is there a h.p. amount or % of boost when it has to be done?
Fiat...so you say a single 1/4" keyway is enough, or you add a single 1/4" keyway and still use the stock one? What you posted above sounds like both. I'm cornfuzed.I do one single 1/4" keyway on everything I have ever built. Never a problem.
Some guys cut the 1/4" key slot right over the existing key slot. Others go 180 degrees from that and cut for a single 1/4 key.
Cutting a keyway is half of it...do you broach the hubs or balancers too, or do most of what you use already come with 1/4" slots?BBC has 3/16 stock.
I always cut 1/4 key opposite the stock key.
But... not my own stuff, it's going to a customer and the extra cannot hurt.
Some stuff comes with 2 1/4 keys and you have no choice but to do something.
If it's a blower hub...and one keyway....I am sure it is 1/4". You do know that there is a different "hub" that is sold for external balance...if you are using an external balance crank. The hub has a counterweight on it.i bought a dc 8-71 blower and now am finally getting around to building the engine i brought the pulley to the shop to get everything balanced and there is only one keyway. so it sounds like i will be all right then. do i make the keyway 1/4" or is it that size already? its on a bbc
One time I built a guy an external balance blown gas deal for a street rod. Was a year later before I happened to catch the guy at the Hot August night deal here.
I asked him how the motor was doing and he said it was a little "too wild" so he and his buddy changed the camshaft to a hydraulic roller deal.
So he fires it up and I notice a lot of "shakin goin on" in the fenders....especially for a blown deal.
Sure enough....he put the external hub on 180 out. It ran a year that way.
LOL yea he thought he had a v-drive.LOL.
Yeah..this guy thought all was normal. Never had a clue. Thought the shakin was cool.
So did the guy at the drags who ran an external balance flexplate on a 427. Wondered why his fenders were always missing bolts.