Clevite & Elgin Cam- Any Good - .488/.488 & 218*/218

[AMX69PHATTY]

Anyone else used Clevite #229-1972 or Elgin #E-1041-P Cam ?
( 1980_Cj is using it in his 401 "ReLoaded" )

Was wunderin' if it's good to 6000 or 6500 in a 10.2:1 360 ?

Tryin' to deal with close Piton to Valve Clearance and
needed a low overlap cam, and these showed 64 degrees
but hopin' it's not "too small".

Do recall some discussion about this cam in 1980_Cj's old post
but do not recall what the "opinions" were.

Thought I'd ask Thanks

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Elgin Cam #E-1041-P specs

..... lift .... adv ... .050 ... Open ..... Close ..... LCTR

IN .488 ... 284 ... 218 .... 4 BTC ... 34 ABC ... 105
.................................. 36 BTC ... 68 ABC
EX .488 ... 284 ... 218 ... 44 BBC ... -6 ATC ... 115
.................................. 76 BBC ... 28 ATC

Overlap 64
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[1980_Cj7]

What's that second line, 36 BTC and 68 ABC, and 76 BBC and 28 ATC?

These cams are soooo confusing, but after fooling around with the degree wheel for many hours, and watching what "our" cam was actually doing, I got to understand them a little better...at least I think.

I think you are wrong on the overlap. "Our" cam has no overlap at all. The first revolution the intake opens at 4* BTC and closes at 34* ABC. The exhaust is closed all this time. The crank comes around the second revolution, and the exhaust opens 44* BBC and closes 6* BTC. The intake is closed all this time. Then, just 2* AFTER the exhaust closes, intake opens again at 4* BTC.

Don't know if you got a cam card with your Elgin, I didn't with my Clevite. I had to call Clevite to find out what the valve events were. Later, somebody found the specs on the Clevite web page and pointed them out to me. I actually drew up a cam card. I can send it to you on Monday, if you'd like.

[AMX69PHATTY]

First line is cam specs at .050 lift.
Second line is cam specs at "advertised" duration, like .005 lift.

Yes, there's a Cam Card "sticker" on side of the box, above numbers came off of it,
and at .050 lift there is almost no overlap, but at .005 lift there is 64 degrees overlap.
In open .005 @ 36 deg BTDC + Ex Close .005 @ 28 deg ATDC = 64 deg overlap.
So yes, at .050 lift there is basically no overlap, maybe 2 degrees.
As pistons rises in bore on exhaust stroke the ex is open,
Ex is closed down to .050 at 6 deg before TDC,
and the Intake has started opening already
and is open .050 2 deg later at 4 deg before TDC,
but it started to open at 36 deg before TDC, at least per the specs
then as piston passes TDC on exhaust stroke
Ex continues to close, "fully" closed at 28 deg after TDC,
and the Intake continues to open further and "chases" the piston down the hole on the intake stroke.
The piston "chases" the Exhaust valve as it closes on the exhaust stroke, and the Intake valve "chases" the piston on the intake stroke.

It would all be so easy to see if blocks and heads were made out of Transparent Aluminum

[1980_Cj7]

Ok, now I understand. I was working strictly with the .050 numbers.

[AMX69PHATTY]

How about that, the packing list / invoice that came with the new ELGIN #E-1041-P cam

says right on it under description #229-1972 ( Clevite part # )