Date: Sun, 24 Jun 2001 21:40:28 -0700
Reply-To: David Marshall <vanagon@VOLKSWAGEN.ORG>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Marshall <vanagon@VOLKSWAGEN.ORG>
Subject: Re: WBX big valve heads and flow bench results
In-Reply-To: <000d01c0fd1c$ad4892a0$2f79ba8c@vern>
Content-Type: text/plain; charset="iso-8859-1"
Looks impressive. I have questions about flow testing like this. What is
the air-pressure we are working with here?
David Marshall - Volkswagen Enthusiast Quesnel, British Columbia, Canada
78 VW Rabbit [1.8L]
84 VW Westfalia with 105hp I4 [For Sale]
84 German Army VW Double Cab [For Sale]
87 Audi 5000 Quattro
87 VW Fox Sedan
88 VW Syncro Double Cab
David's Volkswagen Home Page
http://www.volkswagen.org
Fast Forward Automotive Inc.
http://www.fastforward.ca
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]On Behalf Of
Robert Donalds
Sent: June 24, 2001 7:15 PM
To: vanagon@GERRY.VANAGON.COM
Subject: WBX big valve heads and flow bench results
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