Stealth Head valve seat

[Garys1969RR]

Had a Stealth Head on a 496. When I took it off, and was cleaning the valves, I noticed one ex valve was letting light thru from the chamber side. Re faced the valve, touched up the seat, and still not sealing all the way around the valve.
I can see light in the ex port when shining a flaslite from the chamber side. Any ideas on what could be wrong here? Only on #3 ex valve

 

[Dajkzo]

I would check the valve for any runout and use some prussian blue (or a Sharpie) on the seat after you lap it to see how it's seating.

 

[miller]

Only on #3 ex valve

Might go through the trouble of looking over the seat itself, Gary.
Is it in straight, or maybe was galled when installed? Steel seats in aluminum have to be put in right, before they will seal up right.

(I've had to put dozens of seats in aircraft cylinder heads. Hole has to be cut right, fit right, usually a one shot deal, to get it done.)

 

[Garys1969RR]

Might go through the trouble of looking over the seat itself, Gary.
Is it in straight, or maybe was galled when installed? Steel seats in aluminum have to be put in right, before they will seal up right.

(I've had to put dozens of seats in aircraft cylinder heads. Hole has to be cut right, fit right, usually a one shot deal, to get it done.)

Thanks! Yea the local machine shop worked on it, and opened up the seat with a Quik Way machine, now the valve is sealing way out on the edge of the seat. Not too happy with them. Found a guy in Golden who has been doing HEADS ONLY in his shop behind his house, and sounds like he knows what he's doing. 30 plus years at it. LOL. He's going to replace the seat, and surface the heads. I'll let you know how that works out. He's 3 weeks behind, so that says something right there. Very much in demand!

 

[miller]

Never heard of a Quik Way machine, no matter.

Yup, guide, seat, or both, is off. Takes the right method, especially on the cutting, to keep things in line. Good luck on it!

 

[PRHeads]

Pretty much all typical performance work on heads will put the valve seat/valve interface near or at the outer edge of the valve.
As long as there is an adequate width of contact between the valve and seat for the application, it should be fine.
.060” wide would be fine on a street/strip type of application.

“Kwik Way” is a brand of engine rebuilding equipment that has been around a very long time.
Like Sunnen, Rottler, Van Norman, Storm Vulcan, etc.

 

[Challenger340]

Seat concentricity to the Valve Guide ?

I dunno why anyone would have to replace the seat itself ? Why not just re-machine the Valve Seat Angles in the seat where-ever it's sitting, and make them concentric to the V/Guide itself (within a couple of ten-thousands), and re-grind the Valve the same(within a couple of tenths)

 

[Garys1969RR]

Yes the equip in thus shop

Seat concentricity to the Valve Guide ?

I dunno why anyone would have to replace the seat itself ? Why not just re-machine the Valve Seat Angles in the seat where-ever it's sitting, and make them concentric to the V/Guide itself (within a couple of ten-thousands), and re-grind the Valve the same(within a couple of tenths)

Well I will take it to the head expert and see what he wants to do. The first shop tried to regrind the seat, but I don't think he really knew what he was doing. That didn't work. When I left, he started to bore out the seat without my permission. I realized he was incompetent to replace the seat, so I took the head and left. Now I found a guy that knows what he's doing, 30 years experience. The first guy was pretty young, inexperienced.

 

[451Mopar]

Thanks! Yea the local machine shop worked on it, and opened up the seat with a Quik Way machine, now the valve is sealing way out on the edge of the seat. Not too happy with them. Found a guy in Golden who has been doing HEADS ONLY in his shop behind his house, and sounds like he knows what he's doing. 30 plus years at it. LOL. He's going to replace the seat, and surface the heads. I'll let you know how that works out. He's 3 weeks behind, so that says something right there. Very much in demand!

If your talking about Dave Sarno at SCH Racing Heads, he is in nice guy. He has helped me with several heads, even welded up the B1-B/S heads when it dropped a valve.

 

[Garys1969RR]

If your talking about Dave Sarno at SCH Racing Heads, he is in nice guy. He has helped me with several heads, even welded up the B1-B/S heads when it dropped a valve.

Yes, that's the one! Hey I found a pair of pro comp ported heads for 850. Dropped a valve, messed up the chamber. Is that a good price? Thinking about buying them, and fixing them up.

 

[451Mopar]

I don't know anything on the procomps? I think they are a copy of the Edelbrock Victor heads?
On my Convertibles 505 stroker with the stealth heads, I had Dave do a valve job on them and flow bench test them.
He has also flow tested the B1-B/S heads, Stock MW Victors, Hughes Monster ported MW Victors, and the Trick Flow 240s.

 

[wagonman]

I think I posted before about Stealth heads and leaking seats. A few exhaust seats leaked where there was a chunk of material under them when pressed in. Not only had a leak but the concentricty had to be off as well. The shop had to cut the seats out and had a hard time finding ones to fit.

 

[Garys1969RR]

I think I posted before about Stealth heads and leaking seats. A few exhaust seats leaked where there was a chunk of material under them when pressed in. Not only had a leak but the concentricty had to be off as well. The shop had to cut the seats out and had a hard time finding ones to fit.

Well that makes sense. I will check the other head today for leaks. This motor had leakage past the rings, and at least 1 valve seat so far. This motor has more leaks than the White House! Ha!

 

[miller]

I think I posted before about Stealth heads and leaking seats.

Somebody wasn't holding their mouth right!

 

[PRHeads]

He has also flow tested the B1-B/S heads, Stock MW Victors, Hughes Monster ported MW Victors...

OT I know, but...... I’d be curious to know what the big number was on the monster ported MW heads.

You can send me a PM if you prefer.

 

[furryfrog]

One test I did on my stealths when I bough them was to fill the ports with carb cleaner then letting them sit to see if the valves leaked.

 

[451Mopar]

OT I know, but...... I’d be curious to know what the big number was on the monster ported MW heads.

You can send me a PM if you prefer.

I'll have to find the flow sheet, but it was more than 380+ on Daves bench. I think he flowed then with a 4.25" bore size, and not sure about any shape at the entry to the port?

 

[PRHeads]

Thanks.

You rarely see anyone posting numbers from those heads.

 

[Garys1969RR]

I'll be seeing Dave next week, I can ask him about those heads. Nice to know he has a flow bench.