tman

sounds like a plan, Olli.

azmi951

Now that we have established the chevy valves are the way to go, what size? There are a bunch of different sizes and I assume standard length.

Next question is what guides are used? DO I use a chevy valve guide and band bore out the head to fit it or??????

What is done about the seat? Does it need new seats or does the seat have enough material to be cut to the larger valve?

Thanks guys

evil 944t

930 valves are too short and if you go big valve, why use a 9mm stem??? Chevy valves have been going into 944/951 heads for years.. Do yourself a favor and get some 7mm stems and get some technology from something other than the 80's.

azmi951

I plan to use big block chevy valves but I'm asking what size valve head to use and which guides to buy. the topic of the thread is just a resurrection.

Rogue_Ant

+1


-Rogue

Buckaroo Banzi

+2
I would share if I knew. But I would like to know as well as some others.

It would seem this so called Tech forum would rather be discussing BS drama then real tech issues..
I liken it to pulling teeth trying to get a simple question answered. It would appear from the silence that knowledge is money.


-BB

evil 944t

While your right, some people do make a living off this, it is not the reason why I'm not sharing. There are a few reasons...

1. Its not an easy "bolt on" thing. So, its not an easy thing to write about and answer questions. I don't have time to walk everyone through this on a forum that I check every few days.

C. Every head is different and the guides I use are custom made to the head.

5. For the 3-4 people that would actually understand and carry through with it, there will be 15 people that will tell me I do it wrong. That has grown very old, as old as the amount of drama on this "tech" forum. Especially from the "protected"

Let me give you a "head" start. A 2.7ltr intake valve is 48mm SOooo, you are looking for a BB Chevy valve that is close to 1.890", which will be 1.88 0r 1.90" The most common use a valve 11/32 stem(which is a hair smaller then 9mm). They can be ordered and bought through Ferrea. If your looking for exhaust valves, the can be ordered with a sodium filled stem, see link. Use other pages on the link for intake valves..

http://www.ferrea.com/general-result...tegory_id=6036

You will need all the supporting hardware, guides, seats, locks, retainers, etc...

These are not what I would use but they are good for any street/De car.

Is that enough?

Buckaroo Banzi

Yes, again thank you..

I have a head sitting at a machine shop waiting for me to choose between stock valves or aftermarket. Now I have a better idea what to choose.

-BB

david fracolli

Anyone know where I can get some aftermarket springs to run with stock valves?

Olli Snellman

I hope my friends Pete & Arto can jump into this, because they have already done it. Pete used 2,5L head on his 3.0L buildup (Darton sleeved block). Arto used S2 block with a brand new 2,7L head i managed to buy from a friend in Germany (Thanks again Martin). I am also going to use S2 block and 2,7L head with Chevy BB valves.

George D

This has got to be one of the nicest posts I've seen in a long time. Good information, links, and real help.

George

billthe3

Do you need the 2.7 head to run larger valves like this, or since you're recutting the seats and bowls does it not matter?

The cheap part of me wants to ask if the sodium filled valves are necessary, but I don't want to sound like complete moron. (though if anyone has any thoughts on the subject, feel free to comment)

95ONE

2.02" is the most common chevy valve head size upgrade I've seen. It seems there is waaaay more room for these valves in our head than in most chevy motors. I don't see how those could come close to being a problem.

evil 944t

No, it doesn't matter. You can use a 2.5ltr head but, the dome should be opened. You want to make sure you are not shrouding the valve. Its best to know whats going here BEFORE you break out the dremel, lol.

In regards to the sodium valves, if you don't want to run them, I would consider special coatings. At the end of the day, you want to do your best to control the heat.

billthe3

Yeah, I would assume that since the factory used sodium valves, they are probably needed. Just trying to price things out for how much it would cost to do this, since I am already planning on porting out a head and intake for the car (I just started my high performance power trains class last week at wyotech, so we get to learn how to port the heads and all this fun stuff).