It has been a minute due to life being hectic at work and with kiddos but I am looking to get back into this build. I ordered the Cam spec'd out (thanks Don)from Howards via summit. There is a 8-10 week delay in getting it in my hands. I did get the Melling HV55 pump and pickup and will be installing that as soon as I get a free moment. I also pressure washed the original pan to get it ready. I was looking to start on the heads. I have the stainless valves that I ordered from showcars and was looking for recommendations on springs/retainers/keepers. With the 6-71 huffer in mind I seem to remember that a heavier spring is in order to help with valve float. Any recommendations are much appreciated.
348 assembly
- Thread starter Hods1222
- Start date
I would match the springs to the cams recommendations and you should be good.
Smart move.I would suggest setting the open pressure at around 285 for better cam life.Have you located the rotator eliminators yet?If you're running the "large" 6-71 your boost with a 1-1 drive ratio will come out to a bit over 8 psi.The smaller version with a 10 percent overdrive will come in around 7.5 psi.
I think he will be more than 8 psi with a large 671 Don. I have the large 671 and am 11 percent underdriven and get 8 psi with my 380. Pretty sure Brian was 1:1 with his old small bore 671 to get 8 psi.
Maybe I misunderstood him but I know I’m 11 percent underdriven to get 8 psi on my 380 with large bore 671.
I was looking at some bbc rotator eliminators but the I.D. seems to run a little small at .623 ID. When i measured my 333 heads it seems they are about .700" ID. I could probably open them up with my lathe but they say that they are hardened alloy steel which is doable/undoable with carbide insert based on the hardness level. Any suggestions on where to source some that will work out of the box? I am pretty sure this blower is the large type.. I need to do a little research on it and get busy building a manifold for it.
Get a cutter to cut down the valve guides. You could then step up to a PC type valve seal.
Part #'s for seals are to numerous to mention. Different brands/styles, different part numbers. Just get seals to fit your valve stem diameter AND the od you machine your guide to. The od seal cutters can be had to machine .500, .531, .562 diameters plus others. A problem with the seal cutter is that it may not reach the spring seat. If trying to modify the guides accept the BBC rotator eliminators you will need to machine the od of the guide completely level to the spring seat. Just bore the eliminator in a lathe with carbide tooling. They are just case hardened.
So I was inspired by Ishiftem and his intake build to get busy on my blower intake. I started with a 409 380hp manifold and I started milling down the back portion to get a peek into the upper plane. My plan is to keep everything in the upper plane and eliminate the lower plane. I figure that the the black sharpie areas are where I will mill away/add runners.
I also received my cam from howards, things are coming together slowly..
I also received my cam from howards, things are coming together slowly..
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That gives me nightmares!