Ryno's Cylinder head story.

Ryno · Post by **Ryno** » Sun Mar 15, 2009 5:57 am

OK. It all begins in late August 2008. I am preparing the bus to head to Missouri for the annual BNNTA event.

Checking timing, changing oil, nuts and bolt the entire bus and setting valve clearances. While performing the valve adjust, I find a rocker arm and exhaust valve that are not behaving quite right. So I remove the rocker assembly and check with a straight edge between the intake and exhaust on that cylinder and there's a 1/4" difference between the two. CRAP. Trip canceled. I hook onto our boat with the truck and head up north for a week of fishing instead.

Fast forward to March, my garage is clean and tools are organized, I'm ready for some fun.

I really don't know much about this engine other than it's an AVP rebuild with less than 25K on it.

There's sure gonna be some questions along the way, but I'm confident in my skills and the knowledge here at the IAC.

Post by **Amskeptic** » Sun Mar 15, 2009 12:10 pm

Ryno wrote:OK. It all begins in late August 2008. I am preparing the bus to head to Missouri for the annual BNNTA event.

Checking timing, changing oil, nuts and bolt the entire bus and setting valve clearances. While performing the valve adjust, I find a rocker arm and exhaust valve that are not behaving quite right. So I remove the rocker assembly and check with a straight edge between the intake and exhaust on that cylinder and there's a 1/4" difference between the two. CRAP. Trip canceled. I hook onto our boat with the truck and head up north for a week of fishing instead.

Fast forward to March, my garage is clean and tools are organized, I'm ready for some fun.

I really don't know much about this engine other than it's an AVP rebuild with less than 25K on it.

There's sure gonna be some questions along the way, but I'm confident in my skills and the knowledge here at the IAC.

This is a technical forum. At a bare minimum, we need to know year, make, model, engine specifications, history. Otherwise, if this is going to be a engine rebuild blog, I can move it to the Type2 forum. . . Colin

Ryno · Post by **Ryno** » Sun Mar 15, 2009 2:53 pm

Sorry, 72 riviera with a type 4 AVP rebuild of sorts. Let's move it to Type 2!...Found a sinking exhaust valve on the #2 cylinder this afternoon.

Ryno · Post by **Ryno** » Mon Mar 16, 2009 8:06 am

Well, I brought this head with me to work and I'm going to clean it up in the blast cabinet at lunch. So far, I can see no cracks between the valves.

I am thinking of sending both heads out to Headflow masters to have them re-worked.

Post by **Amskeptic** » Mon Mar 16, 2009 1:37 pm

Ryno wrote:Well, I brought this head with me to work and I'm going to clean it up in the blast cabinet at lunch. So far, I can see no cracks between the valves.

I am thinking of sending both heads out to Headflow masters to have them re-worked.

VW genuine heads?
Colin

Ryno · Post by **Ryno** » Mon Mar 16, 2009 1:52 pm

Amskeptic wrote:
Ryno wrote:Well, I brought this head with me to work and I'm going to clean it up in the blast cabinet at lunch. So far, I can see no cracks between the valves.

I am thinking of sending both heads out to Headflow masters to have them re-worked.
VW genuine heads?
Colin

Yep. At least on the 1/2 side. P/N 022.101.372G

Ryan

Ryno · Post by **Ryno** » Mon Mar 16, 2009 1:59 pm

According to my research, that p/n is for 2000cc. My engine has hydro lifters and a mechanical fuel pump which I'm not so sure is a factory combination.

Colin,

What other information could I get that can give me an idea as to what I have?

TIA
Ryan

Ryno · Post by **Ryno** » Mon Mar 16, 2009 7:03 pm

Pulled the 3/4 head tonight. Had to get nasty with a head stud, but I won. Another VW casting, so that's good. It appears to be in good shape also, but AVP did not seem to care where the sealing ring sat, check it out:

I heard back from headflow masters and they're giving me the option of bigger valves.

Any thoughts on this one without altering cam etc?

I run an SVDA dizzy with 36mm dell orto's.

airkooledchris · Post by **airkooledchris** » Tue Mar 17, 2009 9:20 am

remember that AVP was the ones that reground the cam that is in there currently.
as long as your doing the heads, you may as well do the 9550 cam from RAT as well as the valve train hardware upgrade (switching to solid lifters in the process.)

im interested in how this turns out myself, as with the same rebuilder and a few less miles on mine im just waiting for the day when she blows. (up that is, she kinda blows already)

their head work wasn't exactly something to be proud of when I first saw it:

Ryno · Post by **Ryno** » Tue Mar 17, 2009 10:02 am

Hi Chris, thanks for your input here. I've thought about the Cam and lifters too. I am going to pull the lifters next and have a look at them and then make a decision.

Believe me, if I had the cash, I'd be going with a full out CS engine.

spiffy · Post by **spiffy** » Tue Mar 17, 2009 11:47 am

yeah, you could take the opportunity to do some smart upgrades. Would be waaaaay better to do the cam with better heads. May need to re-vent the dells too.

Where is that ACR guy when you need him?

Ryno · Post by **Ryno** » Wed Mar 18, 2009 1:53 pm

I just heard back from headflow masters on the valve sizes they are:

34x39 for stock and 42x36 for the larger valves.

If I were to stick with the the existing cam, would there be any advantages in going with larger valves?

spiffy · Post by **spiffy** » Wed Mar 18, 2009 2:07 pm

remember that it just isn't the volume but the velocity that is important.

For a stock cam you may want research just a set of nicely ported stock valve size heads. This way you would help out that intake velocity and smooth the exhaust flow thru the port. As you look at advice be careful not to get sucked into the bigger (valve) is better thang. I would also send a pm to the ACR for some more fuud for thought.

Ryno · Post by **Ryno** » Wed Mar 18, 2009 2:17 pm

Thanks for the reply Spiffy. I was really happy with the stock performance of this engine. I just don't have the cash to do an entire rebuild right now, besides, this engine didn't burn oil and always ran good.

Who's ACR?

vdubyah73 · Post by **vdubyah73** » Wed Mar 18, 2009 2:24 pm

big valves were stock for dual carbs, smaller valves were stock for FI.

Itinerant Air-Cooled

Itinerant Air-Cooled

Ryno's Cylinder head story.

Ryno's Cylinder head story.

Re: Ryno's Cylinder head story.