best valves for 8445

[87gnand00ws6]

Im going to get a set of 8445's ported and polished and get a valve job, wich valves would you guys recomend, size etc, i plan on going with larger valves than stock, fill me in on some of the largest valves that fit compforatably in there with no reliablity isues. thanks

 

[Squid4life]

I think most people use Ferrea or Manley severe duty stainless steel valves in 1.775 intake and 1.5 exhaust. That is what I have in mine, (Manley) and haven't seen any bigger on 8445's, but I am new to turbo buicks. I bought a used set here on the boards, but hadn't I found a good set this is where I was going to get mine. He'll also port match intakes:

http://www.cylinderheadspecialties.com

At least the pics will give you a better idea of what they look like. Go to the "our products page" I think it is. Hope this helps!

Squid

 

[frankg]

Both Ferrera and Manley's are good. I like the Ferrera a bit better because they flow a little better. Stock valves work well also when ported properly unless you want to go real fast. Frank

 

[getchasum]

Just in case your interested

I have a set of NEW GM turbo exhaust valves f/s.
These are the correct inconel exhaust valves for turbo appapplication V6, not your standard n/a valves. Brand new GM $30 plus shipping.

 

[sweetv6]

Hi

Ferrera are good it is a parts number

INTAKE : HPP F6238-HI-Flow BU-I 1775 11/32

EXHAUST: HPP F6237-HI-Flow BU-E 1500 11/42

I am not a specialist but i think
it is good for 5 to 6 cfm

IMO

Claude

 

[gofstbuick]

I used SI valves in my most recent rebuild. They offer an in between size to the stock and 1.775 intake valve. I used a 1.745 intake valve. While adding an additonal 30 degree angle to the face of the valves, one intake was slightly bent and the SI company sent one out no charge and didn't even need to see the bent valve.

 

[ThikStik]

Re: Just in case your interested

Originally posted by getchasum
I have a set of NEW GM turbo exhaust valves f/s.
These are the correct inconel exhaust valves for turbo appapplication V6, not your standard n/a valves. Brand new GM $30 plus shipping.

Getschasum,
Do you know what inconel is, a coating i assume? That has me suspicious that my heads which idle smoke, and are recently redone, may have NA valves in them. Of course, if exh valve only is different, this wont matter as it relates to smoking.
Tanks

 

[getchasum]

Re: Re: Just in case your interested

Originally posted by ThikStik
Getschasum,
Do you know what inconel is, a coating i assume? That has me suspicious that my heads which idle smoke, and are recently redone, may have NA valves in them. Of course, if exh valve only is different, this wont matter as it relates to smoking.
Tanks

To tell you the truth I'm not sure what it means. I just know that the Buick Power Source Manual refers to it for turbo appapplication. When you compare a set of exhaust valves from a n/a vs a turbo engine, the exhaust valves have different markings on them. I think it's more of what they are made of. I doubt that the smoke you see is from them not being the correct valves, sounds more like the guides are worn.

BTW....the valves have be SOLD.

 

[UNGN]

Inconel is the brand name of the Nickel Alloy the valves are made of. It's very common in aerospace applications

 

[CTX-SLPR]

Inconel is whats refered to as a Nickel SuperAlloy meaning it has a Nickel base instead of an iron base like steels do. It has some very interesting thermal properties that make it great for high heat applications like turbo exhauste valves and jet turbine components. It is however very expensive and can be hard to cut due to its strength.
I have the manley stainless's waiting for me to finish porting my heads, nice looking pieces. My quetion is what is the durability of titanium intake valves on the street? I know that they aren't recommended for the exhauste valves but what about the intakes?

Thanks,

 

[KendallF]

Originally posted by UNGN
Inconel is the brand name of the Nickel Alloy the valves are made of. It's very common in aerospace applications

Just for info, the stock 8445 exhaust valves are not Inconel. As far as I can tell, the factory did not install different valves in the heads destined for turbo cars at all. The 8445 casting was used on turbo and non-turbo cars, and the markings found on the valves differ by year and probably what parts bin the guy was pulling them out of that day.

I have taken NA heads apart and found the same valves as turbo heads. Also, I have successfully used these heads, including the valves, on turbo motors.

A back cut on a stock valve is worth about a 30% in flow improvement at lifts below .200. See www.gnttype.org and look at the heads section where Ken Mosher has some very good flow bench numbers documenting this. The 1.775 valve has almost no improvement without unshrouding of the chamber wall, and the amount of unshrouding possible on a 3.8" bore is very limited. The 1.775" intake valve with a 1.5" exhaust is the biggest that will fit without radical work such as relocating the valve guides.

 

[UNGN]

Based on the burned valve from a splitfire sparkplug that the previous owner of my car had, I can also tell you that there is nothing special about the material in our exhaust valves.

 

[ThikStik]

Maybe the famed GNX got the inconel valves.