AMC Heads

1


I am about to strip and rebuild my original Syncro engine and I have been looking at head replacements. I am tossing up between importing heads from Go Westy in the US or purchasing in Australia from Tooleys. Below is an exert from there website about how they treat the standard heads claiming the standard heads are problematic.  Has anyone had experience with these problems or fitted the Go Westy heads.  The freight is probably the only factor in fitting the Go Westy heads.


Thanks Greg N 


"We remove all of the valves and scrap them, then replace them with new German-quality valves. We smooth the ports just past the valve seats for better air flow, perform a super quality three-angle valve job, and install brand new OE German quality intake and exhaust valves. It is simply a crime that our competitors sell these cylinder heads straight out of the box and purport them to be satisfactory,


2
Can't comment on the main point, but the gas flowing makes a real difference.
Also suggest crack testing and balancing.
Use the best big end and main bolts and studs that you can find, that is don't recycle.
Peter



--Original Message Text---
From: greg.navarro61@yahoo.com.au [Syncro_T3_Australia]
Date: 08 Apr 2016 17:08:17 -0700








I am about to strip and rebuild my original Syncro engine and I have been looking at head replacements. I am tossing up between importing heads from Go Westy in the US or purchasing in Australia from Tooleys. Below is an exert from there website about how they treat the standard heads claiming the standard heads are problematic. Has anyone had experience with these problems or fitted the Go Westy heads. The freight is probably the only factor in fitting the Go Westy heads.




Thanks Greg N




"We remove all of the valves and scrap them, then replace them with new German-quality valves. We smooth the ports just past the valve seats for better air flow, perform a super quality three-angle valve job, and install brand new OE German quality intake and exhaust valves. It is simply a crime that our competitors sell these cylinder heads straight out of the box and purport them to be satisfactory,








3
I have only rebuilt about half a dozen MV engines, so I don't claim to be an expert, but they are very similar to the air-cooled motor. I must have built fifty of those.

Here's my two-bob's worth;

Cylinder heads and valve gear are the hardest working parts of the engine, and although it is feasible to recondition them, new heads are definitely more reliable in the long run.

This is because few machine shops are set up with the correct jig and step-drill to drill out the valve guides - most of them just drive out the guides with an air-chisel, and remove some of the aluminium at the same time. The new guides, when fitted, then come loose with use.

I have used AMC heads on all of the water-cooled engines without any problems.

They are less prone to cracking than the genuine VW heads.

A friend of mine who runs a cylinder head shop tells me that AMC make heads for diesel trucks, and they are a good product.

However, I have seen one used AMC VW head that had obviously had one of the exhaust valves replaced, as it did not match the other three. This suggests that the valve must have stretched or burnt and was replaced before it failed catastrophically.

Having read the blogs, I decided to err on the side of caution with my next rebuild. I have replaced the valves and collets with OE items.

The quality of the AMC collets has also been questioned.

The AMC valve springs seem fine. They are invariably within spec.

Unfortunately the shop that used to do my engine machining has shut down, and I am looking for a shop with VW experience to port and polish my heads and dynamically balance the crank, pulley and flywheel, balance the rods end for end, and match the pistons.

If anyone out there has found a good operator, please let me know - there are a lot of cowboys out there.

I found it was cheaper to buy OE con-rods than to purchase the new stretch bolts and buy and fit new small-end bushes.

You need to do some research on the main oil seal, as there are some bodgy ones out there that fail. I think it was the GoWesty site that has a good discussion on that issue.

Also important to use engine oil for "Classic" engines, as some modern oils are not compatible with the old-style oil seals.

Hope that is of some help, Greg.

Roger B.
4
I like the AMC heads too but I have seen one that had the spark plug blow out of it along with about a 50c size hole adjacent to it - looked very nasty.

They seem to corrode just the same as original heads too leading to head gasket leaks.

Otherwise they are the best alternative we seem to have apart from a Suby conversion.

Cheers,

Skot

On 9/04/2016 9:16 PM, Roger Bayley gullyraker53@gmail.com [Syncro_T3_Australia] wrote:
I have only rebuilt about half a dozen MV engines, so I don't claim to be an expert, but they are very similar to the air-cooled motor. I must have built fifty of those.

Here's my two-bob's worth;

Cylinder heads and valve gear are the hardest working parts of the engine, and although it is feasible to recondition them, new heads are definitely more reliable in the long run.

This is because few machine shops are set up with the correct jig and step-drill to drill out the valve guides - most of them just drive out the guides with an air-chisel, and remove some of the aluminium at the same time. The new guides, when fitted, then come loose with use.

I have used AMC heads on all of the water-cooled engines without any problems.

They are less prone to cracking than the genuine VW heads.

A friend of mine who runs a cylinder head shop tells me that AMC make heads for diesel trucks, and they are a good product.

However, I have seen one used AMC VW head that had obviously had one of the exhaust valves replaced, as it did not match the other three. This suggests that the valve must have stretched or burnt and was replaced before it failed catastrophically.

Having read the blogs, I decided to err on the side of caution with my next rebuild. I have replaced the valves and collets with OE items.

The quality of the AMC collets has also been questioned.

The AMC valve springs seem fine. They are invariably within spec.

Unfortunately the shop that used to do my engine machining has shut down, and I am looking for a shop with VW experience to port and polish my heads and dynamically balance the crank, pulley and flywheel, balance the rods end for end, and match the pistons.

If anyone out there has found a good operator, please let me know - there are a lot of cowboys out there.

I found it was cheaper to buy OE con-rods than to purchase the new stretch bolts and buy and fit new small-end bushes.

You need to do some research on the main oil seal, as there are some bodgy ones out there that fail. I think it was the GoWesty site that has a good discussion on that issue.

Also important to use engine oil for "Classic" engines, as some modern oils are not compatible with the old-style oil seals.

Hope that is of some help, Greg.

Roger B.

5
all right ..my two bob's worth ..
yep ..totally agree on the need to replace at least the exhaust valves on a new AMC head.
Appreciate the comment on collets too.

re 'head gaskets' or more accurately 'outer rubber coolant sealing gaskets.'

( a super mickey mouse design IMO )
The first AMC head I ever put on a 2.1 waterboxer engine ..back in the 90's ..
showed up leaking badly after less than a year, on that rubber gasket.

I researched that heavily ..
a breakthough occured when a VW Dealer technician told me ..
fit the head without the water gasket and measure the gap there.
And this is what REALLY got me ..
he said "if it's not right, try another head'...
which is insane since parts are suppossed to be very standarized.

so I started doing that for All waterboxer heads..measure that gap ..
I aim for 3.5 mm I think .
Too large and the sealant won't seal after a while,
too small, and the rubber gasket gets pinched and split.

Usually it's not a problem.
I saved that failed-gasket AMC head for years..
i finally found out that it sat very tilted on the cylinder barrels ..
like 4mm on one end, and 6.4 mm on the other end .

so be careful , and these heads don't need just 'installing' ..they need 'careful checking and fitting.'

fwiw ...don't know if you have it there..
but in the US, the BEST by far black silicone sealant is called The Right Stuff ..
and man is it ever !
Comes in aerosol can ..but don't get that version.
get the 'caulking gun' version ..fits in a common house construction type caulking gun

it seals perfectly, cures quickly ..
yet with a nail in the nozzle ...just pull the nail out, and it flows nicely weeks later.
Don't even need any gasket for things like water pumps or oil pans, etc.

if ya mind that gap being fairly proper..
and seal the black rubber gaskets with The Right Stuff ...you won't have a problem there down the line sometime.

scott


On 4/9/2016 2:17 AM, Scott Pitcher spbconsulting@bigpond.com [Syncro_T3_Australia] wrote:

I like the AMC heads too but I have seen one that had the spark plug blow out of it along with about a 50c size hole adjacent to it - looked very nasty.

They seem to corrode just the same as original heads too leading to head gasket leaks.

Otherwise they are the best alternative we seem to have apart from a Suby conversion.

Cheers,

Skot

On 9/04/2016 9:16 PM, Roger Bayley gullyraker53@gmail.com [Syncro_T3_Australia] wrote:
I have only rebuilt about half a dozen MV engines, so I don't claim to be an expert, but they are very similar to the air-cooled motor. I must have built fifty of those.

Here's my two-bob's worth;

Cylinder heads and valve gear are the hardest working parts of the engine, and although it is feasible to recondition them, new heads are definitely more reliable in the long run.

This is because few machine shops are set up with the correct jig and step-drill to drill out the valve guides - most of them just drive out the guides with an air-chisel, and remove some of the aluminium at the same time. The new guides, when fitted, then come loose with use.

I have used AMC heads on all of the water-cooled engines without any problems.

They are less prone to cracking than the genuine VW heads.

A friend of mine who runs a cylinder head shop tells me that AMC make heads for diesel trucks, and they are a good product.

However, I have seen one used AMC VW head that had obviously had one of the exhaust valves replaced, as it did not match the other three. This suggests that the valve must have stretched or burnt and was replaced before it failed catastrophically.

Having read the blogs, I decided to err on the side of caution with my next rebuild. I have replaced the valves and collets with OE items.

The quality of the AMC collets has also been questioned.

The AMC valve springs seem fine. They are invariably within spec.

Unfortunately the shop that used to do my engine machining has shut down, and I am looking for a shop with VW experience to port and polish my heads and dynamically balance the crank, pulley and flywheel, balance the rods end for end, and match the pistons.

If anyone out there has found a good operator, please let me know - there are a lot of cowboys out there.

I found it was cheaper to buy OE con-rods than to purchase the new stretch bolts and buy and fit new small-end bushes.

You need to do some research on the main oil seal, as there are some bodgy ones out there that fail. I think it was the GoWesty site that has a good discussion on that issue.

Also important to use engine oil for "Classic" engines, as some modern oils are not compatible with the old-style oil seals.

Hope that is of some help, Greg.

Roger B.


6
Thanks to all for your valuable comments. Greg N