If they are cnc ported it will be obvious because it will show a surface machined by a tool.
As cast will most likely look like crap like cast does lol.
906 head capabilities?
- Thread starter Csommers
- Start date
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As cast will most likely look like crap like cast does lol.
PRH
Well-Known Member
That was a fat finger deal.
PRH
Well-Known Member
Race type roller cam combos aren’t very forgiving for stuff not being right.
In the long run it’ll likely end up saving you time and $$ to have someone assess the overall set up with the heads, and recommend a course of action to move forward.
famous bob
mopar misfit
I have been running a set of pro comp victor knock offs for about 12-14 ish yrs now , they were fully cnc`d and set up , I did have to finish them and fit to my set up , shim the rocker arms , and enlarge the pushod ho;es..
Getting the pushrod clearance on the heads ended up being a ***** , took 3 times to get clearance .
Are you sure the pushrod holes aren`t shoving the pushrod off the valves ?
My procomps are pretty darn good heads. -flow 354 .600 lift , good street heads...
You are kinda repeating what I said back on page 2. These heads with big offset rockers usually take some grinding in the pushrod holes. You should see what I had to do to my B1 heads for 7/16 tapered pushrods.
famous bob
mopar misfit
I bet !
Csommers
Well-Known Member
So some interesting find. At TDC the piston is .015 in the hole. Al of the exhaust valves are longer than intake. All of the exhaust valves are bent. With clay in the reliefs, the exhaust valve have a clearance of .010 after 3 rotations and the intake valve never touched the clay. Now it’s time to send it to a shop because I’m lost and the heads need new valves and guides
Csommers
Well-Known Member
Pics from the passenger side
Wow, that's fucked up. I think prh nailed it, your valves are probably bbc length.
Your compression ratio should only be around 11.0:1 .
My 470 pistons stick .010 out of the bore after decking.
When your heads get sorted out get yourself a pushrod length checker deal and call up smith bros to have them build you a set.
Your compression ratio should only be around 11.0:1 .
My 470 pistons stick .010 out of the bore after decking.
When your heads get sorted out get yourself a pushrod length checker deal and call up smith bros to have them build you a set.
Csommers
Well-Known Member
So these heads will need valve jobs, valves, guides and possible more pushrod clearance. Would I just be better off starting with a fresh set of Victor heads? Victor heads are gonna set me back $1800 w/o springs.
PRH is in Vermont. Maybe a road trip is in order.
Csommers
Well-Known Member
They are ovaled out and the valves are super sloppy in them
PRH
Well-Known Member
New valves and pushrods aren’t going to solve the valve to piston clearance issue.
To have the in/ex clearance numbers be that far lopsided, it’s likely the cam is installed way retarded.
I would double and triple check the cam installed C/L.
If it’s indeed correct, the easiest way to get more clearance is to run a cam with less duration.
Don’t take this the wrong way…….. but you’re in a bit over your head at this point.
The P/V clearances should have been verified before the heads ever got bolted down.
Measure the valve overall lengths and see if they are close to what I posted previously.
To have the in/ex clearance numbers be that far lopsided, it’s likely the cam is installed way retarded.
I would double and triple check the cam installed C/L.
If it’s indeed correct, the easiest way to get more clearance is to run a cam with less duration.
Don’t take this the wrong way…….. but you’re in a bit over your head at this point.
The P/V clearances should have been verified before the heads ever got bolted down.
Measure the valve overall lengths and see if they are close to what I posted previously.
Csommers
Well-Known Member
PRH
Well-Known Member
Since you say the exhaust are bent, do you think that’s influenced your measurement, or are you pretty confident that’s close?
The ex valve diameter is 1.81?
The ex valve diameter is 1.81?
Csommers
Well-Known Member
PRH
Well-Known Member
Speedmaster shows a 1.81 valve that’s 5.424” long, so that’s likely what are in those heads.
Longer than what they really should be if one were trying get the intake/exhaust tips heights evened out……..and not have to end up sinking the intake valves a bunch to make that happen.
As bent up as those pushrods are, makes me wonder if they were really up to the job.
Longer than what they really should be if one were trying get the intake/exhaust tips heights evened out……..and not have to end up sinking the intake valves a bunch to make that happen.
As bent up as those pushrods are, makes me wonder if they were really up to the job.
Csommers
Well-Known Member
PRH
Well-Known Member
Custom or off the shelf?
Csommers
Well-Known Member
PRH
Well-Known Member
To answer your question though, I don’t think a set of untouched Victor heads are going to help your situation.
Of course, part of that equation will be how much will it cost to rehab the current heads?
Imo, your first move should be to determine the source of the lack of VP clearance.
Of course, part of that equation will be how much will it cost to rehab the current heads?
Imo, your first move should be to determine the source of the lack of VP clearance.
PRH
Well-Known Member
I wasn’t there, and never say never…….. but…….
Since those heads have valves that are .350+ longer than factory heads, then any pushrods designed to work on factory heads…….. in theory would be way short on your heads.
But………mix n match rockers, lifters, cam base circle, etc…….. and you need what you need.
PRH
Well-Known Member
Two different sets of pushrods?
The ones in the first pic are showing obvious contact with the head, and the pushrod cups are black.
The bent ones have pushrod cups that are more of a silver color.
The ones in the first pic are showing obvious contact with the head, and the pushrod cups are black.
The bent ones have pushrod cups that are more of a silver color.
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