I built a 406 SBC years ago, the guy never started it and now I have it back, it's not a real high dollar motor but I do want to use a Hyd Roller cam in it, I'd rather spend the money up front rather than worry about a flat cam. So my question is do I need a reduced base circle cam? Honestly I don't remember if I used the 400 short rod or the 5.7 rod I'm sure I would need the small base cam if it was a 383 but maybe not a 400. The reduced base circle cams are at least $100. more than the std cam. I'm also asking for opinions for retro-fit Hyd roller lifters. What brand? Thanks all!
Yes, get a small base circle. Generally speaking...only high dollar 5.7 rods wth specialty fasteners will clear a standard cam. There is no disadvantage to getting a small base circle hydraulic roller so get it just in case. If you can see the piston there may be a part number stamped on the face. Then you can find out exacltly what piston you have and get the pin height. Since you also know the stroke and deck height you can deduce the rod length. As for cam selection, depends on your heads, compression ratio, vehicle weight, gearing etc. If the heads are stock then get a cam with about 212 degrees at .050 and modest lift with 1.5 rockers. If the heads are performace then get a cam with at least 219 or as much as 240 degrees at .050 and agressive lift with 1.6 rocker. You may want to call Lunati, they'll ask you a few questions and recommend a cam based on your application and goals. Howards Cams offers an agressivly priced link bar retrofit lifter that are made in USA. I have a set, they are fine. I use a Lunati 60111 cam in my 406, it has a great idle, great vacuum, great exhaust note and pulls hard to 5500 rpm. I'm very happy with it. I had a Comp exteme energy cam and it was very noisy becasue Exteme energy cams slam the vavles shut too fast and they bounce off the seat. With a 406 be a bit conservative on the cam becasue they out breath most SBC heads and low buck 406's are all twist and no shout.
As far as smaller base circle, I think you can refer to Dirty Harry's quote... I know what you're thinking. "Did I put in the 5.7 rod , or the 5.5's?" Well, to tell you the truth, in all this excitement I kind of lost track myself. But being as this is a 3.750, the longest stroke Chevy built in a Small Block, and would blow your lobes clean off, you've got to ask yourself one question: Do I feel lucky? Well, do ya, dude? Hoop
LOL, thanks Hoop, I'm not feeling that Lucky! ICS, I will take your advice to a tee! Thanks When I built that motor I milled off a little bit of dome so I'll have to look at the piston itself, I pulled the pan and I think it's a 5.7 I think I will tear it down all the way and hone the block it has a bit of rust in some of the bores Thank you guys! HAMB Rules!
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