cam spec card

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redlined

redlined

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Correct me if I'm wrong, but -15 btc @ .050" does mean the damn pointer on a degree wheel should be to the right side of the TDC mark at .050" lift?
Installed centerline's 111, had to advance the cam a full 8* to get there. Helped the .050" opening number, at least it's at 12* atc instead of 20*. Watching the indicator, the closing point is way screwed too, something to the tune of 78* abdc before the indicator stops moving. Degree wheel's set within a half degree, triple checked it.

Cam specs from the card:
Hughes roller, 9204AL
LSA 114
Installed CL 111
lift .459/.471
duration 192/204
timing @ .050"
intake opens -15* btc
closes 27* abc

exhaust opens 39* bbc
closes 15* atc

So what the hell am I missing here?
 
If you are sure you know what you are doing with the degree wheel we DID have someone on here who did what, got a reverse grind (marine) cam by mistake or some such.

I guess you've seen this...........

[ame]http://www.hughesengines.com/Upload/productInstructions/camshaftsinstallJuly2013X.pdf[/ame]
 
Do you have the heads on it? With any type of hydraulic cam you either need to shim the lifter solid, replace it with a solid, or indicate off the lifter body rather than the plunger or the reading will be different. If you indicate off the valve spring retainer and use checking springs - it will be different too because of the pushrod angles. In terms of the pointer - yes - that sounds right. If the card says the intake valve should be at .050 by 15 degrees before Top Dead Center on the exhaust stroke you should see just that. What the wheel says where the pointer lands may depend on the wheel you have but you should be 15 degrees before (to the right) the TDC mark on the wheel.
 
Was watching the indicator, brought it up to .050" opening, looked at the wheel, it's sitting on 20* atc. What the hell? So I went through the wheel adjustment again, same result.
Thought maybe I was nuts, pulled the chain, advanced the cam 8*, triple checked the wheel before proceeding, now I'm at 12* atc.

No way in hell should the opening point be 35* slow when set straight up.

This is the first Hughes cam I've bought. Like I said, am I reading the card wrong? The MINUS 15 btc as written on the card actually means PLUS 15 atc? If so, why the hell doesn't Dave just put it on the card that way and save simpletons such as myself some confusion?

{Btw, in case you're wondering why I'd want such a weenie roller, it's going in a 4x4 with factory TBI.}
 
Do you have your dial indicator set up with either a solid or modified lifter like Moper mentioned in post #3? You have to use a roller lifter also as a flat tappet won't follow the cam lobe like a roller does. If you don't have it set up like this you may be getting false readings.

IMO I'd degree in the ICL first. Then check the timing events.
 
Sounds like the lifter dropping down,Moper has the best choice. Take a stock lifter,pill the snap ring,DON'T TWEAK IT. pull the plunger & spring. I went to the hardware store,used washers to shim it solid against the plunger & snap ring. This is a trial and error thing. This stuff takes patience, it drives me bananas too.
 
Talked to Tim at Hughes, the minus in front of the btc number does indeed mean atc. Looks like they'd just put 15* atc @ .050" on the card and be done with it.

Got it dialed in with no further problems once I got the meaning of the bassackwards spec.
 
Well OK, but i'm not buying it. "-" is before, or before "at top dead center"

aka Before Top Dead Center.
 
Well one thing about it, if it runs like a dog I can always throw a longer cam in it. May have to anyway, decks are short, static compression came in at 9.33:1.

Waiting on parts, think I'll throw the stock .410" cam in it and see how the opening/closing points compare, and the ICL. Check it straight up with the OEM gears, straight up and 6* advanced with the aftermarket gears. The Hughes installed at 6*. Be educational if nothing else.
 
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