Valve Grinding with a Centerless Valve Grinder

[mustangcobra438]

Daveskustoms...

U are completely wrong about Multiple angle on valve not helping flow. Im not being mean or discrediting u but i can show u back to back flow comparisons.

Keep this in mind for easy hp gains in the future.

The 30* will allow to flow better down low and create less turblance up high aiding in less reversion.

[vontristan19]

I thought it says "This machine does not use a chuck norris to hold the valves during grinding"

[bddc201]

You would have to take a LOT of material off of a surface hardened valve before there would be significant potential for failure. Surface hardening is indeed hardest on a given parts surface, but to a depth of over .03" in some cases. The interior material is still much harder than an untreated component, just slightly softer than the original "surface".

[cameron197040]

that's mad, but next time use some other type of music instead of that doof doof gay repetitive crap

[cbr900rr919]

@cameron197040 this is a learning video what do you want him to play 50 cent which would be even gayer.

[cameron197040]

@cbr900rr919 haha, no! that's still doof doof shit man, so you actually ride a CBR 900rr ? if so, cool man.

[MrKhalio]

all valves are surfaces hardened ,micrometers in depth,if u remove it ,there is no hardened surfaces any more charging valves are deffrent from exusting valves due to high tepreture outlet gases

thanks

[fiatnutz]

@MrKhalio - Say what????

[cbr900rr919]

@fiatnutz i think what he is trying to say is the surfaces that you are grinding are hardened and you are removing the hardened material leaving the valve weak. i dont know where he is getting this from but thats how i took it lol

[germantoyota]

i got one of these at work they are by far the best refacer i have ever used so simple to use

[68pishta68]

Centerless grinding is classified as "without a spindle" and this machine, as you can see, lowers a drive wheel onto the valve stem that is supported between 2 other rollers. Like a dynamometer under the drive wheels of a car, the tires rotate the rollers in the same fashion. You get very precise runout with this style as the support rollers are fixed. 30 degree valve face nets 15 CFM at .400 lift more than a standard 45 on an intake valve. 3-5 angles refer to seat only, backcutting valve yes.

[nightfox272]

the video looks like its from the 70's lol

[geoffp13]

Dude, this is NOT centreless grinding!

[DavesKustoms]

There is no benefit to cutting more than one angle on a valve! The flow is increased with multiple angles cut on the seat. How many and how wide each angle is cut makes a huge difference in flow. Most OE seats are cut with three angles.

[jayguy173]

i use a 30 degree cut for better air flow

[wsimpson86]

The reason you don't want it to get too hot is because the bottom of the valve stem is annealed so its softer so it doesn't snap when the valves close. So if it does get hardened it will snap.

[MrMindfucker]

I alway's cut the valves at two angles. Some valves you cant grind only replace.

[MrKhalio]

HI

If u grinde it, is there any effect on hardened surface material of valves (exuast valve),

thanks

salihi

[billynutz567]

Yes u want to make sure u dont get any kind of hardened metal too hot when grinding it.. it will weaken the metal.. .. LoLz

[michaelovitch]

the valve doesn't heat more than your exhaust gas heat them in this process . there is no modification of the atomic structure of the steel wich should be heaten at more than 1000 degrees celcius to do it.

[ducatiss900]

in reply to marek0086 you tube will not let me post urls so you will have to google "3 angle valve job" w/o" right at the top is an article in chevy hiperformance. you will notice that good valves have a profile right up to the seat angle, yep only 1 angle, it does not matter what comments you make because most people who read this will google the answer and learn that both John and myself are correct

[marek0086]

1 angle valve grind??......BOOO!!! :)

[ducatiss900]

3 angle refers to the valve seat, if you want you can back grind the underside of the inlet valve, usually the exhaust valve is left as is for strength

look up the newen vids for a demo

[marek0086]

no it doesnt!

3 angle refers to the valve-face!

U can have 5-angle jobs and full radiused valve facing.

[ducatiss900]

are you sure, I own a machine shop like John's

[marek0086]

HAHA!!!.....u own a machine shop, and u dont even know what you're talking about !?......oh thats Gold! LOL!

Still, better late than never ; )

[marek0086]

its called a "valve-job"..... not a "valve-seat-job".

[BaytekkDesigns]

marek0086,

Sorry mate, a 3 angle valve job refers to the valve seat being cut at 3 angles, not the valve. ducatiss900 is correct on all counts.

[marek0086]

as comic-book-guy once said..."what is this.... bizzaro world !?"

A valve-job refers to the VALVE!!!!

It CAN include contouring the SEAT.... but its first and fore most the valve FACE that gets the multi angles!

[BaytekkDesigns]

No, just planet Earth, and this is a good as it gets. I digress, a valve job is a nominal term for valve & seat service. You cannot service one without the other sir, to do so would be quite cheap. The seat is still the reference surface of a multi angle valve job hands down, yes you can contour the valve too. It is recommended.

In an all out performance attempt the seat can be countoured up to and then after the seal surface.

[foxsetup]

it look a lot like the End Mills grinder that i use

[thedonofbradford]

haha thats much better than the manual method looks alot more fun too

[enginemasterbuilder]

certainly A lot better than my machine i have in my basement.. heres a good one lyle younker used to use on his smallblocks 37.5 on the valve and 36 interfearence angle on the seat. and he did not use lapping compound . just oil