[urq] WX head build recommendations

Steve Eiche seiche at shadetreesoftware.com
Fri Apr 22 11:47:40 EDT 2005

The biggest drawback to the WX head is that they are failure prone and 
rare.   Unless you are concerned with originality, which you are not if 
you are going to EFI, there is no reason NOT to go with an MC, examples 
of which are dirt cheap and available.  The WX also has 7:1 compression, 
which is lower than the MCs and later Audi turbo engines, so to get the 
same performance out of a WX you will need to run more boost and still 
have less off boost power. 

My recommendation:  If your goal is performance, find an MC and build 
that with the EFI even if that WX head is good.  Pull out the WX with 
CIS and put it on a shelf.   I would also go with EFI that controls 
spark as well, as the ur q ignition system is rather crude and unreliable.


Brandon Rogers wrote:

> The MC head will bolt onto a WX block - however there is, IIRC , an 
> oil galley that needs to sealed off by welding.  I'm sure there are 
> guys who know exactly what I'm talking about.
> Based on my 10V head rebuild a few years ago (2001) I have to agreee 
> 100% with Steve regarding the pressure testing of WX heads.  I had a 
> hell of a time with that.  Chris at Force 5 even pulled a head off a 
> running car for me, only to have it fail the pressure test...
> Brandon
> ----- Original Message ----- From: 
> <Louis-Alain_Richard at computerhorizons.com>
>> Steve,
>> I was with Brady last night: we discussed the merit of some 10V heads 
>> and
>> we have a few questions for you:
>> Is it possible to bolt an MC head on the WX block ?
>> If not, what are the options for a mild street engine with a custom EFI
>> setup ?
>> If he must keep the WX, then what are the drawbacks of this head with
>> regards to cam, valves, flow, lifters, etc ?
>> Thanks in advance,
>> Louis-Alain

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