building head, which valves new casting industrial head with hardened seats

jjona5

Well-known member
So I plan on building my head by the end of summer so I want to add parts to my ebay wish/saved searches list to find deals. What type of valves do you recommend for a mild turbo build? Sodium filled? Stainless? What size? Is another maybe chevy valve a better option?

I plan on running the new casting industrial head with thicker deck, no air injection, and hardened seats(in the shopping cart now).

Are there any verified good writups on minor porting? I really planned on just smoothing the castings.
 
Oh I guess I might have forgotten to put the most important part. The engine will have some form of forced induction. It will probably be turbo as I've enjoyed all of my turbo vehicles and I honestly don't want to deal with a supercharger.
 
There are a lot of variations due to head configurations versus valve availability so a couple questions.

Is this the industrial EFI head with heart shaped combustion chambers?
Would you mind posting the link to these heads?

Are you using the stock cam or an aftermarket cam suited for turbocharging?
 
OK
The EFI head normally uses 4.750" length valves while the pre 1987 300 carburetor heads used 4.810"
The situation is that there aren't any options for the 4.750" long valve.
The 4.810" valves are available in oversize as well as different material.

SI Valves is the supplier for Ford 4.9 six valves.
I recommend stainless steel intake valve and 1.6" Stellite exhaust valve since there will be hard seat inserts.

The EFI combustion chamber walls are in close proximity to the valve head.
Going to the 1.94" oversize intake valve will increase intake flow area but will also increase valve shrouding by the chamber walls.
Of coarse the chamber walls can be contoured back to unshroud the intake valve.
Your choice here on intake valve size.

Some will say that because it is turbocharged a larger intake valve is not important.
I have found that better intake flow means more power with similar boost and/or more power potential at a higher rpm which is important with the undersized ports of the 4.9 six.
The disclaimer here is that I have also seen ports too large that flow high numbers but with lower velocity that didn't produce more power. That is never the problem with the 4.9 six.

Keeping the valve lift well under .500" will allow you to maintain the stock rocker arm components.
Otherwise it will be screw in studs with pushrod guides and hardened side pushrods which is a royal pain and the aftermarket roller rockers will not clear the stock valve cover in most cases.

The longer pre 1987 valves will leave room for spring locators and shims.
You need at least 1.70" from the underside of the spring retainer to the head or spring locator sitting on the head.
If needed you can shim the rockers up and get longer pushrods to compensate for the longer valves in order to get the geometry right.

One of the problems I have experienced with some shops doing head work is the valve stem heights vary way too much which makes it tough to get the valve spring heights and rocker geometry right.
After the valve job is done with the valves installed you should be able to lay a straight edge across the valve tips and have only a few thousand clearance difference between all the valves.

Problem # 2 is having the valve concentric to the seat to within .002"

A good shop should be able to get the job done within these specs.

Later on porting and valve job angles.

Which intake and exhaust manifolds are you looking at using?
 
Stock efi exhaust manifolds and intake. I plan on building a y off my exhaust manifolds for the turbo after having them coated inside and out. I'd like to change the intake later on to something that doesnt go over the top of my injectors and valve cover for ease of operation but for now it will be a budget build. My first step is to get the megasquirt running right on the stock engine and I'll work on building the turbo setup this summer. I only plan on running 5-10 psi. I will probably get the combustion chambers, valves, pistons, and exhaust runner ceramic coated also.
 
Stock efi exhaust manifolds and intake. I plan on building a y off my exhaust manifolds for the turbo after having them coated inside and out. I'd like to change the intake later on to something that doesnt go over the top of my injectors and valve cover for ease of operation but for now it will be a budget build. My first step is to get the megasquirt running right on the stock engine and I'll work on building the turbo setup this summer. I only plan on running 5-10 psi. I will probably get the combustion chambers, valves, pistons, and exhaust runner ceramic coated also.
 
Stock efi exhaust manifolds and intake. I plan on building a y off my exhaust manifolds for the turbo after having them coated inside and out. I'd like to change the intake later on to something that doesnt go over the top of my injectors and valve cover for ease of operation but for now it will be a budget build. My first step is to get the megasquirt running right on the stock engine and I'll work on building the turbo setup this summer. I only plan on running 5-10 psi. I will probably get the combustion chambers, valves, pistons, and exhaust runner ceramic coated also.
 
Stock efi exhaust manifolds and intake. I plan on building a y off my exhaust manifolds for the turbo after having them coated inside and out. I'd like to change the intake later on to something that doesnt go over the top of my injectors and valve cover for ease of operation but for now it will be a budget build. My first step is to get the megasquirt running right on the stock engine and I'll work on building the turbo setup this summer. I only plan on running 5-10 psi. I will probably get the combustion chambers, valves, pistons, and exhaust runner ceramic coated also.
 
Stock efi exhaust manifolds and intake. I plan on building a y off my exhaust manifolds for the turbo after having them coated inside and out. I'd like to change the intake later on to something that doesnt go over the top of my injectors and valve cover for ease of operation but for now it will be a budget build. My first step is to get the megasquirt running right on the stock engine and I'll work on building the turbo setup this summer. I only plan on running 5-10 psi. I will probably get the combustion chambers, valves, pistons, and exhaust runner ceramic coated also.
 
Stock efi exhaust manifolds and intake. I plan on building a y off my exhaust manifolds for the turbo after having them coated inside and out. I'd like to change the intake later on to something that doesnt go over the top of my injectors and valve cover for ease of operation but for now it will be a budget build. My first step is to get the megasquirt running right on the stock engine and I'll work on building the turbo setup this summer. I only plan on running 5-10 psi. I will probably get the combustion chambers, valves, pistons, and exhaust runner ceramic coated also.
 
Not sure what happened there. I kept getting a website error when I posted. Guess it went through after all.
 
jjona5":2za4vbza said:
Stock efi exhaust manifolds and intake. I plan on building a y off my exhaust manifolds for the turbo after having them coated inside and out. I'd like to change the intake later on to something that doesnt go over the top of my injectors and valve cover for ease of operation but for now it will be a budget build. My first step is to get the megasquirt running right on the stock engine and I'll work on building the turbo setup this summer. I only plan on running 5-10 psi. I will probably get the combustion chambers, valves, pistons, and exhaust runner ceramic coated also.

The piston is the only part that will benefit with any significance with a ceramic coating.
By reducing heat transfer to the piston there is less expansion as well as less reduction in material strength.

We have tried several valve coatings in our supercharged engines with bad results including coating failure which screwed up valve sealing.
The combustion chamber doesn't benefit since it is cooled by the water jackets.
Besides all of the above, 10 lbs of boost doesn't pose much of a heat problem unless you are looking at very long periods of time under boost.

You can build a plenum that bolts to the bottom half of the stock EFI intake and bolt the throttle body to the front of it.
 
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