Originally Posted by danglerb

I know nothing of the details of porting, but those look like round holes, wouldn't it be fairly easy to make them larger round holes?

Easiest place to host picts is right here, just become a full member.

Second choice is, http://www.imagehosting.com/index.php totally easy, no signup, browse, upload, and copy the link.

Originally Posted by Hacker-Pschorr

Has anyone measured the valve spacing? Meaning the distance between the center of each valve? Yes I realize they are (should be) the same, just curious.

Originally Posted by 918-S

Sure, but there is some real science involved in porting heads. It's not as simple as hogging out material. Done incorrectly and you can actually end up with worse heads than you started with. The euro heads have Porsches engineers behind the work that was done.

That's dumb. You have to be a member to post photos that would benifit the people that are interested in these cars and how they work. I don't own a 928. I own a 914. So I'm too cheap to become a member.

Originally Posted by danglerb

Science would be great, but I suspect some "cookbook" level porting will improve just about any factory head. Chances are good Porsche's engineer's had goals like good fuel economy and ease of production, not getting the last 10 or 20 hp out of the motor. Can't say at this point I disagree with that view, stock Euro S heads sound fine to me.

No you don't have to be a member, just use the link I posted and put a link to the images in the thread if it won't let you put the actual image in, or PM a link to somebody that is a member and let them post the images.

Originally Posted by Olli Snellman

Just use Chevy big block valves. Lot's of different kind available for good price.
Here my friends head with Manley made Chevy valves. Those are also bigger than 930 valves

Originally Posted by 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.

Originally Posted by 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?

Originally Posted by 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.

Originally Posted by Hacker-Pschorr

Keep in mind the valves in a 944/951 head are farther apart compared to a 928 head. Not sure how much this will limit the size of the valves you can install.

I'm sure somebody has those measurements lying around.

Originally Posted by Fabio421

I thought the heads were the same.

Originally Posted by Fabio421

There was talk at one time about the feasability of putting 944/951 heads on a 928.