Date:         Sun, 24 Jun 2001 22:14:36 -0400
Reply-To:     Robert Donalds <bostneng@FCL-US.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Robert Donalds <bostneng@FCL-US.NET>
Subject:      WBX big valve heads and flow bench results
Content-Type: multipart/alternative;

Fellow vanagon types

I have been building a 2.1 engine for my own 85 camper and along with the usual upgrades of the reground OEM cam with more duration, a little more piston skirt clearance and some major head work. I decided to try a set of larger valves and larger harder valve seats. After all the work to get larger valves and seats into a pair of AMC heads and doing the high flow valve job I sent the heads out to have them flow tested on a flow bench. The flow bench measures cubic feet of air moving threw each port at a given valve lift. Some of you might recall that I had some flow testing done when I started doing high flow valve jobs on stock heads with varying degrees of porting work. 

Flow bench test results
1 stock AMC head intake port 
2 ported and polished AMC head stock valve intake port 
3 Boston Bobs big valve AMC head minor porting  

                 CFM.
-------------------------------------------------------------------             
 Lift           NO.1intake  NO.2 intake  NO.3 intake     
.050           24.8            33.0              34.8
.100           47.1            52.2              57.3
.200           89.6            91.4             108.4
.250         115.4           116.7            132.8        
.300         125.3           128.5            145.8
.350         137.6           145.3            171.4
.400         144.9           158.8            181.3        this is above stock lift but I thought it was of interest
.450         147.8           174.1            186.0        to Robert Lilly 
.500         154.6           179.0            190.6

as you can see I am very pleased with the results.
I am tempted but wont be using ratio rockers 
maybe a chip if they have them for the 85 fuel injection system next year
no dyno testing will be done unless your paying 
no estimates of horse power wiil be offered 
I am still installing the engine and will report on power when its sorted out
at that point I will decide whether to offer the large valve heads on my rebuilt 
engines  
  
Bob Donalds 
http://www.bostonengine 

as always all rights reserved



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