STD heads: cam lift, duration and other specs Shovel specs

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STD heads: cam lift, duration and other specs Shovel specs

Postby 55FL » Tue Sep 12, 2006 8:29 am

Post by 55fl on Jan 4, 2005, 6:06am

This falls under the realm of idle curiosity but.... I was wondering... with the design of the STD heads do the cam lift, duration and other specs follow the stock Pan or more closely approximate the Shovel specs ?
Just one of those things that makes me wonder.


Post by King on Jan 4, 2005, 7:03pm


Good question. I assume that since the STDs use the stock Pan rockers that the rest of the cam/valve train specs remain ala Pan, but i could be wrong. It will be good to hear from the more experienced members on this one.


Post by panomania on Jan 4, 2005, 7:57pm

the heads i bought did not come with the rocker arms, i used the ones off my 50 model heads. so i assume the lift with the push rods adjuster correctly wouldnt change anything. i bought mine with shovel type intake manifold and valves. i like em...panp

Post by Mbskeam on Jan 5, 2005, 4:28am

the valve lift is pan specs, the ports on my stock style std's are diff from stock heads. this what the exhaust port looks like.
the intake is the same but it also has a raised floor on the intake side ( bigger ports do not mean it will run better)


best money I've spent

Post by kell on Jan 6, 2005, 3:18am

You can run a cam with up to .550 lift with the STD pan heads.

Post by Rammy on Jan 7, 2005, 1:21am

I just put on a set of the plumber intake STD heads on my 51. the thing I noted with the shovel sized intake is that their is very close valve to valve clearance with cam overlap. pans rocker ratio is more than on shovels so I would be wicked careful with to much cam... I figured a good way to check this : put a bright light up to the exaust spigot and look in the intake port then turn over very slowly until the valves are at their closest point , then take a 8 inch long piece of welding rod you know the stuf like coat hanger , bend it to look like a hockey stick so you can put it down the plug hole like a feeler gage . before you stick it in put it flat on an anvil or the like and hammer it a little at a time until you can just slide it between the valves , when it fits then mic it and you will have your clearance. with the Andrews J cam I have .070 between the valves.
Any body know if the J cam would work ? I think .050 is the lower limit....

Post by Rammy on Jan 7, 2005, 1:25am

I ment the A cam , any body know if that would go

Post by Mbskeam on Jan 7, 2005, 2:23am

I run the A grind and have not had a problem, I think .060 is the safe min. I would not go any smaller on this clearance,OR

A: you would be left on the side of the road crying as you pick up your bent and busted parts left all over the road,

B: or maybe just a bent valve or two,

but if you have the luck I have it would be A.........


Post by Rammy on Jan 8, 2005, 3:41pm

I here the A cam has much better all around performance than the J
What do you think ?
How does performance compare from old heads to STD heads?
I have my ride all back together and running sweet but don`t think it would be a good idea to test ride it in the snow we just got! Head are a work of art ;D

Post by Mbskeam on Jan 9, 2005, 12:50am

well I like the cam I have.I use to run a sifton 412 I liked it also, between the two it did start a little better. but that is the trade off of more valve lift. the 412 I think had a bit more low end, mid was the same, but when the engine gets to mid and up the A starts to hump.
The 412 and J are kinda close on specs but are diff. its more like a smaller lift A grind
As for the diff. in head performance. that is to be seen as I only got about 1200 miles on the rebuilds rebuild (see spun cam bearing)I have not beaten it to hard YET, if it brakes I'll fix it that what machines are for. It does seem to start better,unless a crowd is around watching, well you know............
and up in the NW its been cold and icy, so no riding on the back roads I live on.I feel your pain on this.

Post by sleeper on Jan 9, 2005, 7:20am

I agree w/ya the 412 has a little more on the bottom
But the A has it from mid & up . Much more IMO..

I remember your spun bearing pics. Glad you're back together again.

I've been getting some 'personal riding time' in myself.
My stroker is getting the "easy does it" break-in.
But I can already tell, It's got a lot more BALLS.. ;D
And sounds much stronger....Too ;D
Breaking-in miles are the hardest miles to put on.
But as you say, It's all Good !!

Post by King on Jan 11, 2005, 2:42pm

Three years ago I converted to STD heads and have never regretted that decision. My original heads had pocketed and trashed valve seats that were way beyond another grind. So it was time for some radical change. My local guru strongly and wisely advised against steel inserts and at the time the valve seat build-up techniques were still in their infancy. So STD heads it was.
The boost in performance was amazing and the old dear has been running strong ever since. Also starting is much easier both cold and hot. Though I admit to an anal obsession with points gap and timing, cold starting is just a couple of squirts (Bendix) and a couple of kicks, and I can get three out of four hot starts on the first kick ( But you know that forth one still is a bitch!!).
I give STD an A+ on their excellent product and I hope their heads work as well for you as they have for me.


Post by gordon on Jan 12, 2005, 6:34am

Ordered a set of STD heads about a month ago , they should be ready to pick up in a few weeks . I ordered them with shovel O ring intakes,pan cyl. bolt pattern and 3 bolt exhaust flange, valves, springs,and rocker arm studs installed.............Pricey little suckers! The rest of the motor is almost done just waiting on the heads. I drove to there factory to place my order for these and walked in the back door of the shop by mistake and just stood there like a kid in a candy store. There were panheads EVERYWHERE! Boxes full of em' They even had sum cool shelving units made out of stacked bare panheads with boards on top for the shelves! And they were using them for door stops and paper weights too. javascript:adds(%22:o%22)

Post by krazyloop on Mar 4, 2005, 6:22am

An Andrews A grind cam has a max lift of .470 and will fit right into shovel heads with no head work. It will not cause the valves to strike each other. In a shovel the lift is slightly less than in a pan and to be safe I had 3/32ths ground off the top of my valve guides in my pan. I used 10 to 1 stroker 80 pistons for 4.25 stroke and did not have a problem with valves striking each other, nor did the valves hit the pistons.
STD heads come with stock clearances for a .550 lift so you should have a lot of clearance with an A grind or any Sifton .468 series for that matter. STD will give you more clearance if you ask them to. You cannot use a Sifton .468+ in motors much less than 90 inches because the duration is so large. You won't have that problem with an A grind. On the other hand, because the duration is much less than a .468+, I suspect an A grind may not be enough cam for a 90 inch or bigger motor.

Post by 65flh5326 on Mar 27, 2005, 8:00am

I have read with wonder and amazment about problems cutting out the bronze panhead seats and pressing in steel seats.
I have done this to at least 100 sets in the last 26years. Not once has a seat fell out.
It is a pain in the ass to do it, and there is judgement involved.
I also would never put shovel intake valves in panheads.
The only time I have seen problems doing this is when automotive shops do it, they just dont know aircooled engines.


Post by Grottorian on Mar 20, 2006, 3:42am

I have STD dual plug heads. They have a problem with the exhaust valve guide leaking oil out the front pipe. I'm running a B grind cam. Ive got a 1000 miles on the engine. Gotta pull the head cause of the oil problem.

Post by Mbskeam on Mar 20, 2006, 4:42am

do you mean past the valve guide seals, or on the outside around the guide and head?
please expand on this.....

look at your head gaskets and make sure that it is not pullin oil in from the return oil passage

Post by grottorian on Mar 30, 2006, 3:10am

Oil comes out the back of the pipe & leaks out of the pipe where it hooks up to the head. The front pipe is worse & the back is starting to. I don't know if it's leaking out around the guide or seals. I guess the heads weren't set up right? I bought them assembled & supposed to handle 550 lift.

Post by Mbskeam on Mar 30, 2006, 4:00am

may just be the guide seals,
did you over rev and smack them, and or your heads are not set up the way that you think, for lift.....


got over 6,000 on mine and no problem like this....

Post by kell on Mar 30, 2006, 10:49pm

Somebody told me once that oil seeping out through the head gasket can get sucked into the header where it clamps on the spigot. See if your bike has a black streak going from the head gasket to the exhaust header?

Post by panacea on Mar 31, 2006, 1:20am

Grotorian, does it puff blue smoke when accellerating? how about decellerating?...MW

Post by Grottosblues on Mar 31, 2006, 3:29am

Yes it does puff smoke after it's warm - I notice it at a light - & when I rev it. I've never over reved it. I've been running it pretty strong after 500 miles. I think it is the seals - but wonder why - Ive gotta pull it back down again.

Post by grottorian on Apr 1, 2006, 3:21am

I'm running a B grind cam with Jims Powerglide Hydraulics. Is that ok - or do I have to go to a BH grind? Re: STD Heads
Post by panacea on Apr 1, 2006, 4:04am

Grottorian,If it was leaking from the seals, I would think smoke on decell would be more pronounced.I've been wrong before, you don't suspect rings or scuffed piston?..MW

Post by panacea on Apr 1, 2006, 4:06am

Is it black smoke or blue?..MW

Post by grottorian on Apr 1, 2006, 11:07am

It's black smoke

Post by grottorian on Apr 1, 2006, 11:13am

There is no black streak coming from the head gasket. When I had the heads off a couple months ago the cylinders & pistons looked good.

Post by panacea on Apr 1, 2006, 2:42pm

Black smoke sounds like rich fuel mix...MW

Post by grottorian on Apr 1, 2006, 10:44pm

I'm wrong - it's white/grey smoke. I think we're gonna pull the B cam out & put in a BH. Hope that will fix it.

Post by fourthgear on Apr 1, 2006, 11:29pm

If oil is coming out around the head exh. pipe next to head and your burning that kind of smoke , you may have guide seals leaking but ,I would look at a head gasket . What type did you use? Fire ring , Teflon ? A lot of times you will find that oil gets blown out of the exh. pipe because of exhaust pressure finding the easiest route. How do your plugs look ? they will tell the tale for sure about whats going on in the combustion chamber. If you blew the head gasket by the oil passage it will give you oil that you will see in and around the pipe not to mention some burning oil smoke.Of course you will probably have to remove the heads for inspection if plugs tell a tale. How do your valve cover gaskets look?

Post by grottorian on Apr 2, 2006, 8:25pm

The valve cover gaskets look fine - no leaks - The plugs look good - I used the S&S recommended copper gaskets for the heads. I used the old style gaskets fiber (or whatever they are) when I put it together last year & blew one - so changed to the copper. The gaskets could be leaking some I guess.

Post by fourthgear on Apr 4, 2006, 2:57pm

I've got down to only using the James blue Teflon head gaskets in all the HD's I have worked on since they came out with them. I have had problems with all the others and since I don't have problems with the blues , its a no brainer to me . If your plugs look good and not oil fouled , you may just have blow by from your new rings ( a possibility) It could be just wet soot from an exhaust leak , leaking by. Even that sounds funny. Why did you think it was valve seals? Any oil in the combustion chamber will leave its calling card on the plugs , chamber and it will eventually foul the plug . So if your plugs are not getting oil fouled and you are getting oil leaks it could be external and walking toward the exh. pipe. Burning whitish gray smoke, that would also show up on the plugs in one form or another.Did you pressure test the intake manifold when motor was assembled?

Post by grottorian on Apr 5, 2006, 12:08am

I took the pipes off & looked into the head from the exhaust port. It looks like a black oil/tar trail coming from the valve - but behind it looks dry- guess that means valve seal or exhaust leak? The pipe gaskets did look to be leaking some - so I replaced them. I don't trust the head gaskets - How can I tell if they're leaking? No, I didnt pressure test it. Andrews told me to switch to a thinner oil 20w50 - so I'm gonna try that too. Got 500 miles on the motor now - gonna try to get the bugs out - thanks for help!!

Post by Mbskeam on Apr 5, 2006, 6:20am

well... if you can see it coming down the valve from the guide, then it may just be that....
did you have these heads built by some one, or did they come set up from STD.
in a production environment shit happens sometimes. somebody may have been having a bad day.
in a parts run I sometimes get a part that is way out of spec, then its off to get a print and check other parts in stock, and sometimes its off to the scrap bin, as I said shit happens.....


Post by fourthgear on Apr 5, 2006, 12:53pm

If your plugs are burning good with no build up chances are your head gaskets are OK , I know thats saying a lot by not seeing anything in person but the reading of spark plugs tell you a lot about how your motor is running.
I think changing to , thinner oil as you say may not help your problem , it may enhance it . mbskeam is on the money , shit happens and if its produced in quantity there will be mistakes made sooner or later. You may just have a bad seal on that valve . You do not have a lot of miles on your motor yet and some take longer to break in and that includes seals and rings. I'm not saying it may go away ,but I would keep an eye on it and if you need to pull the head and replace the seal ,so be it . If STD assembled the heads I would be in touch with them and tell them about the problem, ya never know they may have had a run of bad seals and may be able to help ya out .

Post by grottorian on Apr 5, 2006, 3:54pm

The plugs look like : The insulator is brownish - the outside is black - sooty - Theyre dual plug heads - the left side is blacker than the right, which looks better. The tip is blacker than I'd think - should be. Both cylinders look about the same. I guess that could be dialing in the carb... I don't think there's oil fouling going on. Yes - these were assembled heads. Andrews reason for the thinner oil was cause my motor is new parts -S&S - T&O, STD - that the tighter tolerances would call for thinner oil.......

Post by harleydoug on Jun 8, 2006, 4:13am

Sounds like valve seals to me. The teflon ones get scored during installation sometimes and are worse than no seals at all. Getting back to cam specs in panheads, the rocker ratio is different than a shovel, so the shovel specs are "short" on both lift and duration. A 514 S & S cam has an actual lift of 542 in a pan and 514 in a shovel. At the same time it is listed as having a 246 degree duration in a shovel, but has about 250 degrees in a pan. If you use shovel specs for selecting a cam for a pan, you need to check it when you install it. The magic .550 that S T D says it's heads can take is true, but your cam might be more than that in your pan. A "C" grind andrews in a STD panhead will have the valves run together and bind in a pan, but this cam will work nicely in a shovel
This is just a matter of "simple" geometry. If the cam is measured at .053 lift, and the rocker moves faster in a pan because of the ratio, then the valve will open sooner and faster than a shovel. At the same time, there will be more lift and more overlap at TDC. Add in the fact that the STD heads use larger valves than the stock panheads, and it stands to reason that some of us are living on the very edge of a major collision inside the combustion chamber.

Post by grottorian on Jun 25, 2006, 2:46am

The valve seals were bad. I replaced them & fixed that problem. Also the front pipe was sucking oil up from the crankcase breather hose - hense wet pipe - shoulda figured that sooner. I rerouted that. Also - I put the F cam in & am gonna switch to an A soon. The F's good when the R's are up but my low end power's gone now.
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