Bob, did the exact opposite for me.
1.9 AMC heads with Big Valves on a 2.1
Compression is higher than stock.
I was trying to build a motor similar to the DJ out of an MV.
My pistons are not domed.
Just talked to EricD. and may buy his DJ wiring to see if any more HP can be produced.

dylan

________________________________
From: Mike Collum <collum@VERIZON.NET>
To: vanagon@GERRY.VANAGON.COM
Sent: Sunday, January 25, 2009 7:08:02 PM
Subject: Re: heads- bus depot or van cafe??

Scott Daniel - Turbovans wrote:
> I hear there is just one head for either 1.9 or
> 2.1 wbxr engines. is that true ?
> if so, did they compromise on the compression ratio .....or what ?

Back in 2001 I installed a "1.9" AMC head on my '84 7 passenger.� It's
still doing fine.� They've since discontinued the 1.9 heads and are only
selling 2.1 heads (no compromise).

2.1 heads can be used on a 1.9 as long as they're used in pairs.� When
installed on a 1.9, the compression is a tad less than if 1.9 heads are
used.

My Boston Bob 2.1 engine was fitted with AMC heads with different valves
and a special grind.� I carefully looked over the gasket area before
installing all the bolt on stuff and they appear uniform all the way around.

Mike