posted 09-27-2000 09:19 PM               

I've just bought a pair of Aussie 2V closed chamber heads ($US 55 pr). I'd like to try swapping them for my current 2V open heads.

At this stage I'd like to do the mimimum possible to get them working, and spend money on hardened seats etc later if the heads work as well as they are supposed to.

The heads are currently stock, small multi groove valves, single springs etc. Guide wear was about 5-10 thou for the couple I checked. Chamber volumes were around 60-61 cc for the 3 I checked. Assuming 40 thou for the gasket and ignoring the small notch in the piston gives almost 12:1 theoretical. This is too high, and I intend to clean up the chambers and get it down to 10.5 or 11:1 ????

I understand that the multi groove keepers are to allow the valve to rotate & even up wear. But they also don't clamp on the valve? Is it possible to file a little off the keepers to get them to clamp the valve?

Dan, you mentioned in a previous post (to the guy with the Iso) that 2V valves give teh better flow due to less shrouding? Can you elaborate?

I'm also interested in any advice on porting these heads?? Help! There is quite a lip in the head between the intake valve and the gasket line. Is this area worth smoothing out? Short turns? Gasket matching? In the chamber?

I've checked out spring bind and it's no good. The heads come with shims under the valves (I didn't measure but 100 thou would be my guess until I do), but even then I'd still be binding I think. Also the retainer can only take the outer spring.

What do you guys think, can I get these heads on with a few simple changes like springs etc, or do I risk a dropped valve? Should I just wait 'til I've got the time and budget and put single groove valves, keepers etc???

posted 09-28-2000 02:22 PM               

I've never seen any reason for hardened seats in any U.S. Cleveland
heads. Here's a post you may find interesting:

"Inserted seats are for repair. They interfere with heat flow from the valve;
the ports have to be ground to blend the seat in; improper installation (can
you tell with your naked eye?) will let them come loose, with potential for
catastrophe. The cutting necessary to install the seats weakens the head and
can promote cracking, particularly if the head is subjected to higher than
stock pressures or heat, ie a high performance engine.

You want inserted seats about as badly as you want a veneral disease.

Most shops call them "hardened" seats; most inserts are plain old cast iron,
like they just carved out of your heads. True hard seats are Stellite and they
cost over $10 each, and they're righteous bastards to cut a seat on."

>Assuming 40 thou for the gasket and ignoring the small notch in the
>piston gives almost 12:1 theoretical. This is too high, and I intend
>to clean up the chambers and get it down to 10.5 or 11:1 ????

I'm assuming you have domed pistons to get that compression ratio.
A few of the Pantera guys in the club have found that they had small
domed pistons and quench heads and were running around 11.5:1 compression
and were able to make it run on 93 octane by backing off the timing curve.
Flat tops and quench heads are preferred, though. Polish the chambers,
open the areas around the valves to take some CC's out. You still
may be pushing it. I dunno. I've always run flat tops and quenchers.

>I understand that the multi groove keepers are to allow the valve to rotate
>& even up wear. But they also don't clamp on the valve? Is it possible to
>file a little off the keepers to get them to clamp the valve?

Maybe but don't trust it. You've still got the head popping problem.
That's what destroyed my freshly rebuilt 351C. A friend destroyed two
Clevelands with brand new sets of FoMoCo valves. A guy in the club did
the same.

>Dan, you mentioned in a previous post (to the guy with the Iso) that 2V
>valves give the better flow due to less shrouding? Can you elaborate?

It's not due to less shrouding. It's due to a better short side radius
and better match to the port size. With a larger valve, the turn can't
be made as gentle. The optimum might be between 2.05" and 2.19", but
2.05" is better than 2.19". even with 4V heads, a slightly smaller intake
(2.15") is better unless bore size is 4.060" or larger.

>I'm also interested in any advice on porting these heads?? Help! There is
>quite a lip in the head between the intake valve and the gasket line. Is
>this area worth smoothing out?

I'm not sure what you're referring to.

>Short turns? Gasket matching? In the chamber?

If you're running a Weiand Xcelerator, you'll need to port match because the
manifolds ports are larger than the head's. Taper the port match as far down
as possible (gradual area change). Work the area under the valve and smooth
the short side radius. Raise the roof and gasket match to headers.

>I've checked out spring bind and it's no good. The heads come with shims
>under the valves (I didn't measure but 100 thou would be my guess until I do),
>but even then I'd still be binding I think. Also the retainer can only take
>the outer spring.

You should be able swap the open chamber stuff over, as others have pointed out.

posted 09-28-2000 03:20 PM               

quote:

---

Originally posted by Daniel Jones:
I've never seen any reason for hardened seats in any U.S. Cleveland
heads. Here's a post you may find interesting:

"Inserted seats are for repair. They interfere with heat flow from the valve;
the ports have to be ground to blend the seat in; improper installation (can
you tell with your naked eye?) will let them come loose, with potential for
catastrophe. The cutting necessary to install the seats weakens the head and
can promote cracking, particularly if the head is subjected to higher than
stock pressures or heat, ie a high performance engine.

You want inserted seats about as badly as you want a veneral disease.

Most shops call them "hardened" seats; most inserts are plain old cast iron,
like they just carved out of your heads. True hard seats are Stellite and they
cost over $10 each, and they're righteous bastards to cut a seat on."

Dan Jones

---

I would recognize that tone of voice anywhere. It's Dave Williams! Right Dan?

posted 09-28-2000 03:27 PM               

The 443 FE he did for Sean Korb is quite interesting.

posted 09-28-2000 04:39 PM               

I was planning on getting back on Fordnatics eventually but heard it's down.

posted 09-28-2000 05:21 PM               

------------------
Marcus
Fast, Reliable, Cheap.... Pick any TWO of these words.
68 Mustang, still in purgatory.
BOYCOTT EXCESSIVE MOTORSPORTS

posted 09-28-2000 06:01 PM               

The details are probably still up at www.chucko.com
and archives at http://www.listquest.com/lq/search.html?ln=fordnatics

I don't really know how to describe it, I guess like one of our forums, with out a lot of the peronal interplay betwen parties.
Dan was a member, David cole was a member, I can't remember if I saw Ted there too, or just the in usenet. I lurked there, just trying to gather useful info

posted 10-02-2000 09:26 PM               

There seems to be some confusion. Currently I'm running open 2V heads with 4V valves (intakes machined to 2.125). These heads were professionally built and have single piece, single groove valves etc. Pistons are flat top with a small cutout.

I can swap all the good bits from the current heads to the closed chamber heads, but it would mean taking the car off the road for a while to get all the machining done. I'd like to just try the closed heads first (check for detonation etc), and do them up properly later if they work well.

Bossman, yes I can get the pistons notched, but at this stage it's easier to remove the metal out of the heads than to pull out the pistons. And I'm going to polish and tidy up the chambers anyway.

Daniel J. I've got hardened seats (they must be because I payed lots more than $10 each) because I run on propane most of the time, and usually lean. Interesting comments about the short turns. Seems to be a critical area? I have both Weiand and Performer intakes. I've seen a couple of references now that quote 3 % increase in HP with each full point increase in compression. Not much? Quench heads should give a few % too, from additinal turbulence. Steve once quoted 50 HP difference between open and closed Cleveland heads - sounds to good to be true?