[TR] long TR4 inlet manifold in a TR3A/B ?

francois wildi fwildi at yahoo.com
Thu Mar 18 05:18:27 MST 2010

Yes I measured 80mm height on the regular and 115 on the long one. Gee.
Yes, by wedge I mean adjusting the angle of the carb flange which more vertical on the TR4.

I went to show my project to the guys at our mechanical shop downstairs. For some reason, they always have a kind of a grin when they see me coming with old hardware. But they are always ready to help. The present idea is to saw off the cylinder head side flanges, shorten the tubes a bit, may be 15mm (they are nearly straight on the head side), counter sink the flanges a bit and TIG weld it back to the tubes. I love this idea! I had one mechanics promise me he'd teach me how to TIG weld. We were just waiting for an opportunity.

We'll see what reasonably feasible. And then I'll see if I can fit my K+N, my 2" horns or whatever else on the carbs inlet.


--- On Wed, 3/17/10, Geo Hahn <ahwahneetr at gmail.com> wrote:

> From: Geo Hahn <ahwahneetr at gmail.com>
> Subject: Re: [TR] long TR4 inlet manifold in a TR3A/B ?
> To: "francois wildi" <fwildi at yahoo.com>
> Cc: triumphs at autox.team.net
> Date: Wednesday, March 17, 2010, 2:31 AM
> Oh my.. a voice from the distant
> past!
> I just did a quick rough comparison and it looks to me like
> the TR3
> manifold is 3.75" v the TR4's 5.125" -- a lot of extra
> distance to
> squeeze in there.
> By 'wedge the carb side' are you referring to the need to
> get the H6
> carb at the correct angle (since the TR4 manifold presents
> a nearly
> vertical surface)?
> Sounds to me like you're going to end up with a 'power
> bulge' someplace.
> Geo
> On 3/16/10, francois wildi <fwildi at yahoo.com>
> wrote:
> > ...the idea of fitting
> > a long TR4 manifold on the TR3. Not much clearance on
> the R/h inner fender
> > side. The manifold really does look very long...
> really really long. I will
> > make a direct comparison tomorrow at work between a
> extra regular manifold I
> > have and that long one. I can probably shave a
> millimeter or 2 on each side,
> > wedge the carb side and even maybe the engine side a
> bit. But will it
> > suffice?

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