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engine & steering clearance
02GF74 - 9/12/09 at 08:39 AM

I'll try again seeing as my previous post went down like a lead zepellin

1. how much clearance should I allow for engine moving forwards? Is 10 mm enough?
2. How much clearance between outside of steering shaft and chassis?

The shaft "wobbles" due to UJ and I can flex it a bit - I suspect when driving it can bounce up/down a bit but unlikely to do that sideways but I will allow for that. I am thinking 5 mm from max deflection would be enough?

turbodisplay - 9/12/09 at 09:13 AM

Have you thought of runnning a bearing to keep the uj in check? The IVA inspector might not like the uj moving.
Darren

theconrodkid - 9/12/09 at 10:11 AM

i used a rose joint as a bearing for the shaft,kept it out of the way and rock steady

blakep82 - 9/12/09 at 10:29 AM

i vote rose joint too. 10mm clearance should be ok i think. depends on how much your engine can move though. seem to remember the first book saying 1/2" was the minimum clearance for things like that

02GF74 - 9/12/09 at 10:46 AM

re: rose joints and stuff.

the wobbling is nothing unusual as the shaft has tol move due to having 2 UJs and 2 shafts at an angle.

Now the bendy bit is that I can grab the extended shaft from steering wheel to UJ and can flex it. ....... now I am wondering if it is too small a diameter

(this is all post SVA)

blakep82 - 9/12/09 at 12:23 PM

quote:
Originally posted by 02GF74
re: rose joints and stuff.

the wobbling is nothing unusual as the shaft has tol move due to having 2 UJs and 2 shafts at an angle.


mine doesn't...

speedyxjs - 9/12/09 at 12:32 PM

quote:
Originally posted by blakep82
quote:
Originally posted by 02GF74
re: rose joints and stuff.

the wobbling is nothing unusual as the shaft has tol move due to having 2 UJs and 2 shafts at an angle.


mine doesn't...


Neither does mine. I have two UJ's with a bearing between them.

MikeR - 9/12/09 at 12:32 PM

Because of the positioning of my rack with two uj's i used a ...... anti roll bar block. 18mm was perfect fit to my 17.5mm shaft.

pewe - 9/12/09 at 12:48 PM

^^ Great minds and all that....
Mine has 2 UJ's and a VW collapsible bush.
Mr SVA reckoned it flexed too much.
Not wanting to take it all apart I used a 2 piece anti-rollbar block (Merlin Motorsport or agricultural suppliers) reamed out to size and mounted on a plate hung off the chassis.
This obviously needs to be on a straight run where it's not trying to articulate.
Seems to be lasting quite well.
Cheers, Pewe

[Edited on 9/12/09 by pewe]

02GF74 - 9/12/09 at 01:40 PM

quote:
Originally posted by blakep82


mine doesn't...



hmm, I must be wrong then. So the shaft has been welded off centre, hmmm, more stuff to take apart and investigate?

incidentally what would be minimum steering shaft diameter if made from mild steel?

charliemouse - 9/12/09 at 02:27 PM

Hi,

Ive built and rebuilt about 20 7's - and steering shaft clearance has been an issue on a few (this includes Westfields and the like!). The main factor is the compliance in the engine mount. We now sell 'low compliance' cortina type round units. They only allow 5mm or so of movement. Had them from the factors in the past that have allowed 2" in the gap between shaft and oil-pump on a x-flow to result in a groove in the alloy pump end plate after just 5 runs up Harwewood. A fix for this can be a steel 'cup' around the rubber (a piece of pipe the size of the rubber welded to a circular base with a whole for the mount bolt to pass through.). This reduces movement to almost zero and doesnt affect NVH too much...

Regards

Nik