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Re: power boost

To: Anne Garren <algarren@main.nc.us>, spitfires@autox.team.net
Subject: Re: power boost
From: Glenn Trunnell <trunnell@earthlink.net>
Date: Tue, 18 Jun 2002 21:25:40 -0400
Anne,

This is kind of a loaded question!  In order to maximize any power gains 
a header and a free flowing exhaust are mandatory, but I am concerned 
about your carb choice.  Usually when someone uses a single sidedraft 
weber they use the 45 DCOE instead of the 40.  I'm not saying that it 
won't work but it may require a lot of tuning.  The sidedraft webers 
require a fair amount of tuning anyway.  The other problem is that 
you're starting with the lowest output 1500 engine also, about 48 hp 
stock so you,ve got aways to go.  My advice would be this:  Sell the 
weber on e-bay, buy a set of the European dual SUs (the HS4s not the 
HS2s, Ted Schumacher at www.tsimportedauto.com can hook you up), install 
these, get a decent header and free flowing exhaust (check out the 
maniflow units at APT, www.apt.com or www.aptfast.com, I can't remember 
which) and install these.  You can also remove the cylinder head and 
have it machined to raise the compression to at least 9:1 but no more 
than 9.5:1.  Finally you could change the cam to one of the fast road 
profiles that are around, but that would be the last thing I would look 
at. All this assumes that your engine has good compression, good 
ignition, cooling etc. I can assure you of one thing however that if you 
bolt that weber on without any tuning or other modifications, that 
you'll be lucky just to come out with the same power you had before. I 
live in Pittsboro, NC and I'll be glad to offer all the help I can. 
 There are a few shops locally that specialize in British cars and I can 
refer you to them if you like and i'd be glad to help you work on your 
car if you feel like a trip to the piedmont! But honestly, I think the 
weber would be a waste of money for you.  Sorry to be a bummer, good luck.

Glenn Trunnell

Anne Garren wrote:

>Hi everyone,
>
>I think there may have been a thread on this recently, and I apologize if I am
>covering it again but I've lost track. I've got a stock '73 Spit and I'd like
>a little more oomph to enjoy the mountains here in western NC without making
>huge modifications/investments. I've bought a single Weber 40 DCOE (thanks
>Huw!) to put on the car, and I've heard I need a new header and exhaust
>system. So, I am seeking the expertise of this list. Is the Performance header
>offered by Moss and their stainless steel exhaust system what I need?
>
>Any tips/advice/suggestions will be appreciated!
>Anne

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