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New Project Starting Soon

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After a LOT of thought I decided to replace my current piston rings with a set of Perfect Circle (Mahle) moly rings and install the larger high performance 2.190"/1.88" valves in my 1966/1967 closed-chamber 396"/427" heads. So I just bought a used Kwik Way valve grinding machine and a Black & Decker valve seat grinder set that has all of the standard mandrels and stones from 1-1/8" to 2-1/2". I haven't ground any valves or seats since about 1985 but I know what I'm doing.

The 365 hp thru 390 hp 454's basically use the old 396" 325 hp heads with the smaller 2.06"/1.72" valves so they quit breathing around 4800-5000 rpm when used on a 454". So the larger valves will help them breathe easier at the higher rpm's; especially with my .556" lift magnum camshaft. When I do the valve installation I'll also do some minor bowl cleaning and take pictures along the way.

I'll wait until the weather cools down into the high 70's/low 80's so maybe a month from now I'll get started.
 

LLC5

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Looking forward to your adventure.

Hopefully it cools down soon.....
 

Tom Bryant

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It should be an interesting project. I haven't ground a valve since 1968.

Tom
 
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Before the present child labor laws came into being we got jobs when we were 16 years old. I got an after school and weekend job grinding valves and seats at the local machine shop to fund my high school gasoline expenses. The usual was 272" thru 312" Fords, 265" thru 283" Chevys, a couple of 348" Chevys, 332" thru 390" Fords, inline 6 cylinder Fords and Chevys, and 318" thru 383" Mopars. Some VW's, Datsuns, Toyotas, and such but I did get a REAL experience on a overhead cam Jaguar head that used hardened shims on the tops of the valves.

The larger high performance valves in my low performance closed chamber heads should give them about 500 rpm more. The smaller 2.06"/1.72" valves were adequate for the 325 hp 396's but those smaller valves strangle the larger 454's at the higher revs. So the larger valves should yield an improvement. And besides that I am bored and need something to keep me busy.

Before I dive into my engine I'll restore and paint the valve grinding machine so it'll look spiffy and check/replace the brushes on the Black & Decker valve seat grinder motor. I am used to using air powered Sioux motors so an electric motor will be new to me.
 
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Oval Ports...............Really?

I just noticed the title "New Project Starting Soon" is missing the "J" in project. Hmm. Old age perhaps?

I have been looking at all the oval port heads Summit Racing sells and none of them really have "oval" ports but rather "kinda sorta" oval ports. They are really short rectangular ports with rounded corners to make them appear to be a little bit oval. My Air Gap intake ports are exactly matched to my head ports which were exactly matched to the FelPro gaskets. But they are still OVAL.
 

Toms007

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Thank you for fixing that glaring error. I try to be very careful in my choice of words, spelling, and grammar so I don't appear to be retarded but sometimes things just happen.

The new 2.19" intake valves will be 6% larger and the 1.88" exhaust valves will be 8.5% larger so it should spin past 5000 rpm a bit easier. Other than the smaller intake ports my heads will duplicate the early 396" and 427" high performance heads that were used prior to the open chamber versions that arrived in 1970. If I were really serious about high-rpm horsepower I'd install a set of '87 open chamber heads and a set of .220" dome pistons to keep my compression ratio around 10 to 1. But as this is just my daily driver and seldom gets revved beyond 3500 rpm it's not that important to me.
 

GTR1999

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I used one of those old B&D valve grinders about 33 years ago when I had a job in an automotive machine shop for a while. There was an indicator that fit on the guides to check the seats and I wanted to dial in every seat I ground to get it the best I could. The owner didn't want me to spend the time doing that, just grind and assemble! Clearly that wasn't my approach then or now and I left that job. He only used a single bolt on boring head and got mad once when I asked why he didn't use a torque plate or have a better bore/hone machine. I don't think he was in business for a long time and that was back when rebuilding engines was feasible for both the customer and shop owner. Boy have times changed.
 
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I used one of those old B&D valve grinders about 33 years ago when I had a job in an automotive machine shop for a while. There was an indicator that fit on the guides to check the seats and I wanted to dial in every seat I ground to get it the best I could. The owner didn't want me to spend the time doing that, just grind and assemble! Clearly that wasn't my approach then or now and I left that job. He only used a single bolt on boring head and got mad once when I asked why he didn't use a torque plate or have a better bore/hone machine. I don't think he was in business for a long time and that was back when rebuilding engines was feasible for both the customer and shop owner. Boy have times changed.


I have never used a dial indicator on seats but rather sprayed graphite on the valve face then "snapped" the valve against the seat. If it showed an imprint all the way around I knew it was good. Many engines used 30 degree intake valves and 45 degree exhaust valves and I never understood why ANY valve would have a 30 degree seat because a 30 degree valve doesn't "self center" like a 45 degree valve would. And I always lapped diesel valves to make absolutely sure they didn't leak because their valves and seats are often VERY hard and the cylinder pressures were so high. And speaking of "hard" the International Harvester 305's and 354's had seats that were so hard only the extremely soft "white" stones would touch them and the stones had to be "dressed" each time they were used because they would "groove" so easily. As this area has a lot of orange trees there are many wind machines operating in the winter months and those wind machine engines run at a full throttle at about 3500 rpm. I installed many 7/16" stem sodium filled stellite-faced exhaust valves and stellite seats in those heads; usually 292" and 312" Fords but now days most are powered by 460" Fords and 454" Chevys running on propane. Because of the "dry" propane they must use hard seats to prevent valve seat recession. I have seen many small block Chevys with seats so recessed the adjustment nut couldn't be backed off any further; seats about 1/4" deep and about 1/4" wide.

My goal is to make my low performance heads as good as possible without spending a lot of money on them. And as I'm running a 236/236 degree camshaft with a .556" valve lift the larger valves will compliment the camshaft. The oval ports have about 3 square inches of area and with the .556" lift and 2-1/8" valve diameter (measured at the center of the valve face) the valves will have an open "window" of about 2.71 square inches. So the breathing above 5000 rpm should be better.
 
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kpic

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TBTR.....
All castings have fillet or corner radii unless it is where 2 cores meet. Cores would also include glue pieces. Castings are quite interesting.
No an oval port is not really what anyone would consider a true oval. Simply said, it is a rectangle with larger corner radii. Look at the pictures.
Oval: https://www.cartechbooks.com/media/wysiwyg/techtips/killerbbchevy/SA190_7-2.jpg
Rectangular: https://www.cartechbooks.com/media/wysiwyg/techtips/killerbbchevy/SA190_7-3.jpg
Whole article: Techtips - Big-Block Chevy Cylinder Head Basics

Basically, oval means the 4 corner radii are numerically larger. The larger radius reduces the flow area as compared to a smaller radius.
2.190 - 2.06 = .130 or .065 radially; you do not want a choke point where it feeds the cylinder. Choke means necking it down where the flow goes. In forced induction it is called a forward facing step in the air passage. The 6% larger only counts if it is a correctly setup 6%.
The 1.88 from 1.72 exhaust is an entirely different situation.

Unless they are designed for the chamber volumes you have; I have no clue what your .220 "dome" pistons will net as a CR. I doubt your "guess-ti-mate" of 550 RPM more. As the typical non-engineering type you're missing a lot.

LLC5: Oh boy, buckle your seatbelt; here we go again. :chuckle
.






 
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Vintage Black & Decker Valve Grinding Machine

After I bought the valve grinding machine I discovered it's a Black & Decker; not a Kwik Way. But it appears to be 100% complete and the seller told me it still works. It has two v-belts and they're both REAL frayed so I'll be replacing them along with the electrical cords, toggle switches, plugs and receptacles, and re-paint it. I really don't need it but as I'm also buying the valve seat grinder set I felt it would be best to have both. I saw two others just like mine on E-Bay selling for $800 so I came out okay. I am always looking for things to do so this machine will keep me busy for a good week.

The Black & Decker valve seat grinding set I bought appears to have all of the popular "inch size" mandrels and a LOT of stones and it also appears to have about 6 long and short stone holders. My new valves, piston rings, gasket set, and ? should arrive via UPS this morning. I could have bought larger valves but I felt the standard "high performance" valves were large enough for my oval port heads. Can't wait to get started on my new project.
 
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High Performance Valves

My new 2.190" intake and 1.88" exhaust valves arrived today. Here's some pictures showing the difference in sizes. They are Manley stainless steel "Street Flo" and they have hard-chromed stems and hardened tips as well as being undercut and swirl polished. The intake valves have a face only 3/32" wide but the exhausts have a face 1/8" wide. Darned nice valves for the price. And Perfect Circle rings are now Mahle rings (Germany).
 

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LLC5

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kpic

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Many engines used 30 degree intake valves and 45 degree exhaust valves and I never understood why ANY valve would have a 30 degree seat because a 30 degree valve doesn't "self center" like a 45 degree valve would.

Centering is controlled by the valve guide.

The reason is flow of the fuel air mixture keeping it from separating and compound angles do it best. The OEMs have been using a CNC to cut 3 angles for years. The 30 degree is the "top angle."

"Valve Seat Dynamics

One area of critical importance is the valve seats. Valves slam against the valve seat thousands of times per minute at high revs. The air flowing past that valve seat is turbulent and frenetic. The sooner you can start the airflow over the seat, the more air you can get in and out of the engine. And the smoother that air flow is over the seat and valve, the more air can be pumped into the engine to make more horsepower.

From the factory most engines come with a three angle valve job done on CNC machines. As shown in this picture, the seat is not located directly on the edge of the valve, but instead a few millimeters back into the valve seat. The actual valve seat angle is generally 45 degrees. On the combustion-chamber side of the 45-degree seat is a top angle that is usually around 30 degrees. This top angle serves two purposes. First, it acts as a radius to transition air between the 45-degree seat and the combustion chamber. Second, the top cut is used to reduce the width of the 45-degree seat from the top.

The third angle is usually called the throat angle and it also has two functions. Its primary task is to transition air between the 45-degree seat angle and the port. The throat angle also reduces the width of the 45-degree seat angle from the bottom"
Competition Valve Job Explained

http://www.tpr.co.jp/tp_e/products/valveseats/images/img_vs_about_02.gif

The above shows how the diameter of the valve seat insert matches up with the valve seat's sealing surface.
 
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The Dart heads on my '82 came with 7 angles on the valve seats. The seats appeared to be rounded until I examined them with a 10X magnifying glass.

And large-valve heads that use 30 degree intake seats tended to wear the valve guides oval because the 30 degree valve and seat lacked the "self centering" ability of the 45 degree valves and seats. I actually ran across several foreign heads that had BRASS seats. No kidding, and they were very hard to grind because the stone loaded up so fast. I had to use oil on the stone to help prevent the loading.

As I had looked at many valve grinding machines I made a simple mistake about which brand I bought because the Black & Decker and Kwik Ways are both painted red. So get over it.

My seat grinding equipment will arrive tomorrow morning so the first thing I'll do is inventory everything to see if it's all there. As the set is so old I doubt it'll have any metric pilots. It appeared to contain about 6 stone holders; two long ones and four short ones.
 
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You Tube Video

I watched a You Tube video this morning of a guy installing a set of 2.30" intake valves in oval port heads. I had considered installing 2.25" valves but felt the factory sizes of high performance valves would be a better choice for my daily driver that is seldom revved beyond 3500 rpm. I just wanted it to breathe a bit easier around the 5000 rpm mark.

For the last 50 years I have been using VERY worn out carbide burrs for cylinder head work. They are chipped and dull so I just bought $88 worth of new burrs; four being 6" long and the other dozen of various shapes. I use carbide burrs real often for other metal working jobs so I felt it was time to buy some new ones. They are no doubt made in China but for cast iron or aluminum they'll easily do the job. For aluminum jobs I keep them sprayed with WD-40 to keep them from getting loaded and I'll often submerge them into water to keep them cooler.

I can hardly wait to start in on this new project. As I wanted to replace the piston rings anyway because of high oil consumption this will be the perfect opportunity to install the larger valves.

These Manley valves are really well made and surprisingly inexpensive as each set was around $110. My present valves are Sealed Power and only the exhausts have hard tips. These Manley valves have hard tips on the intakes and exhausts to limit wear. And as I'm running full roller rocker arms the wear will be almost ZERO.
 

LLC5

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Difference In Valve Sizes

A new exhaust valve is only 3/16" smaller in diameter than an old intake valve. The smaller valves were adequate for the 325 hp 396's but they aren't nearly large enough for any of the 454's.

And I have noticed all of the aftermarket aluminum oval port heads use the larger 2.19"/1.88" valves. I wish my heads were the later open chamber style but I have to work with what I have.
 
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Black & Decker Valve Seat Grinding Equipment

My Black & Decker valve seat grinding equipment arrived at noon and I immediately dove into it to take inventory of it's contents. It has about 30 grinding stones which is good because new stones cost around $12 to $14 each. It also came with a LOT of adjustable pilots but 75% of them are no good because the 3-wing "expander" at the bottom is either broken or missing. But I have two of the 5/16", 11/32", and 3/8" adjustable pilots that are in good shape so I have what I need. It has the heavy duty cast iron stone dressing stand with a good diamond and the motor runs good. The motor's brushes look like new. It came with a total of 7 stone holders; 3 short length, 3 medium length, 3 long length, and one that has 11/16" threads for using Kwik Way stones. The steel box it came in has two drawers and the box is in very good condition.

As my new Manley Street Flo 2.19" intake valves are so big I had to order three new 2-3/8" stones and I also ordered two 4-ounce containers of valve lapping compound (one fine and one coarse). I use it for various jobs and I was almost out so I ordered more. It's supposed to get back into the low 100's in a couple of days so I'll wait until the weather cools off before I jerk my engine out.

My Black & Decker valve grinder is supposed to arrive around September 19th but I won't be needing it because I'm installing new valves. It looks like it's a 1950's vintage because it has two exposed 3/8" belts and a lot of it's original red paint is gone. But as long as it works that's all that I care about. Used Sioux equipment is VERY expensive; like $3000 to $4000 and that's way out of my price range so this Black & Decker is just fine for what I need it for. The Black & Decker valve grinder also has a rocker arm and lifter grinding attachment on the right end where the tips of the valve stems can be ground square.
 
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