Thread: Cam Ident.

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Pulled a Cam from a sbc 350, I cant seem to find any info on it. Markings are as follows: dist end, "BABE", "100TDP HYD" , "B14" , "485" (the 5 is upside down) ; between the first couple of lobes "EPI"... Any help would be great!
Also the block seems to be giving me some conflict, casting number 3932386 ; stamped numbers below the head 19J180287 ; VII27HH (clearly not v11 but vii) this is a 4.03 bore and a 2 bolt main, crank casting number 3932386 crank also has TAK957 stamped on it.
Any thoughts and comments are welcome.
Thanks,
LOST

Block casting for two bolt is= 1969 327 but could also be early 350. Both were made with the same block. Cast in Saginaw, Mich. Assembled in Flint, Mich.

4.030 bore means it has been rebuilt and the cam is anybodys guess. What are the journal sizes on the crank? check the backside of the bearings and see who the manufacturer was.. Clevite, Fed-Mogul, DAB (Michigan). MOST factory engines have Moraine 400 or 420 on the bearings.

Bearings are Clevite main and rod are .010's. I measure main 2.440 and rod is 2.090. The bore measures 4.026 pistons measure 4.001 this seem odd? piston have no markings at all flat on top only one long eyebrow for valve relief.
The engine was given to me by a friend, the main bearings show some sign of wear (some shinny covering gone in some areas leaving a copper color) but the bores have no ridge top or bottom I can still see alot of the cross hatch in the bores, piston skirts have nearly no wear on them. I have some 76cc heads to go on it and I plan on replacing main & rod bearings, rings, lifters, timing chain and seals/gaskets. their was a very small amount of surface rust in a couple of the cylinder bores (set in the back of a van with no heads for years) but when I turned the crank 10 or 15 rounds nearly all of it went away,(I plan on removing the rest with a soft wire brush). I will also clean it completely before reassembly) all parts were clearly numbered to insure I put them back in the same spots.
Any advice for someone planing on going this route?
thanks,
LOST

Best guess on the cam would be one of Babe Erson's. He died a while ago but I think the profiles were picked up by a grinder in Riverside or Corona, California.

Regards, Mark

Measure your piston skists down about an inch from the pin. Then record the measurement. Measure your bore about 1/2 the way down. There is something wrong here!. The pistons could be Hi-perf stuff. Many versions were made but your piston to wall clearance can't be over about .004" with a forging and a cast piston at about .0025" max. Looks like you have over .020" which would make a mighty noisy engine. Like somebody put standard pistons in a .030 hole.

I get old guys in the shop that have small engines bored .010-.030" and then try to use std bore pistons in them. I just can't seem to get it into their head that you can't do that.. Or they want to put .020" rings into a std bore. Still no good guys!!

Ah thanks, measured several of the pistons again near the skirt 4.025 to 4.027 I can not measure to far in the bore I only have a dial caliper (and it never reads the same number twice). so I take it I need .030 over rings?
No luck on the grind of the cam. I checked Erson-cams listings the part numbers and grind numbers were not the same type, I was really excited that might be it (I did alot of searching trying to find it before asking for help in this forum).
Thanks again,
LOST

Keep in mind there used to be both Sig Erson and Babe Erson Cams. Two separate companies. I believe Sig Erson Cams evolved into Erson Cams.

Babe Erson seemed into the more "fringe" applications rather than the mainstream. I had one of his BBC turbo cams on a dually until a couple of years ago when it lost a lobe. I remember seeing his decals on 1/4 midget cars, rally cars, oddball stuff.

If you search the web you may be able to find someone who still has a catalog.

Regards, Mark

You will need .030" rings. 4.025-4.027 would be about correct for a piston in a .030" bore. Most of the single valve slot pistons were forged. If you would like to know the lift on that cam.. You can measure it with the vernier. First measure the lobe on the side. (lowest reading, base circle), then measure it top of lobe to base circle. Subtract base circle from top of lobe figure. Then multiply the result by 1.5 (rocker ratio) and you will get the lift figure.

Thanks,
I will check the lift tonight, any way of getting an idea of duration?
I would also like to get an idea of the compression ratio of the pistons because I am putting some 76cc heads on it need to know about how thick a head gasket I will need or any other mods short of changing the pistons, my goal is between 9.5:1 or 10:1.
A few more questions are what are some of the tall-tell signs that a rotating assembly has been balanced? I have noticed that metal (welds) were used to partially fill some of the thumb size holes in the crank. The end caps of the rods have been ground down some and are smooth.
The top of the piston scratched with little effort using the sharp end of a screwdriver, felt like aluminum to me, how would one tell if these are forged?
Thanks for all the help.
LOST

You will need a degree wheel and a dial indicator to check duration. Usually you can get a pretty good idea of the duration if you know the lift. They go, somewhat, hand in hand.

You will need a thin head gasket to get decent compression ratio. I believe a flat top piston with 64cc head is around the low side of 10-1 so go from there. I think the Keith Black site has a compression ratio calculator www.k-bsilvolite.com


The welding in the counterweight holes and the rod caps being ground are indicators that the engine was balanced.

MOST forged aluminum pistons look very smooth on the underside. No lines or waffling marks. The area around the pin tends to be solid all the way up to the underside of the piston top. On the outside of the piston, a forging will not have any cast in type numbers or mold marks. Usually smooth on both sides of the pin in the skirt area. No cast numbers or patterns.

Tho the modern pistons are made similar and a novice would have a hard time identifying them from a forging.