Clearance

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SAE30
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Post Tue May 05, 2009 8:46 am

On my swap i used some funky engine mounts to get the desired engine height but the engine is still tilted, im gonna be using the stuff that works, i.e the e36 motor arms and the 535 rubber mounts, what i need to know is 'How much clearance or space must there be between the sump and the cross member/ steering rack?' i test fitted the mountings but it looks very very close...

Please help
penton08
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Post Tue May 05, 2009 8:52 am

i can just about squeze my chubby fingers in there!!! with the e30 rack and a s50 fitted.
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SAE30
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Post Tue May 05, 2009 11:40 am

so i suppose this is tooooo close???


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GeoffBob
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Post Tue May 05, 2009 11:50 am

Can't really see in there from the angle of your pic, but I would say that that is indeed a bit on the close side. chances are two things will happen: (1) Under heavy acceleration the back of the pan will collide with the rack, and (2) as your engine mountings compress and sag with age the rear section of the sump will come to rest on top of your rack and cross-member. Looks to me like you need to go upwards and forwards.
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Post Tue May 05, 2009 12:51 pm

Is there any way of moving the rack downwards slightly? Can't picture whether it's the highest point or not. :?
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SAE30
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Post Tue May 05, 2009 3:50 pm

The pic i posted is not with the e36 arms and 535 mounts thats why its sooo low, what is the SAFE amount of space to have between the rack and the sump
GeoffBob
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Post Tue May 05, 2009 4:28 pm

I would personally recommend 25mm vertical clearance on brand new rubbers. Regardless of which rubbers you put in, they will sag by roughly 10mm with time. You'll need about 20mm clearance between the front of the rack and rear of the pan. That's roughly enough space to stick your hand into, at a squeeze.

If your sump starts rubbing or knocking on your rack or cross member you'll know it, so if in doubt, open the gap up a bit. Better safe than sorry!
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SAE30
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Post Wed May 06, 2009 8:27 am

GeoffBob wrote:I would personally recommend 25mm vertical clearance on brand new rubbers. Regardless of which rubbers you put in, they will sag by roughly 10mm with time. You'll need about 20mm clearance between the front of the rack and rear of the pan. That's roughly enough space to stick your hand into, at a squeeze.

If your sump starts rubbing or knocking on your rack or cross member you'll know it, so if in doubt, open the gap up a bit. Better safe than sorry!
thanks... i think im gonna use one or two spacers with the mounts as well just to be sure
ian332isport
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Post Wed May 06, 2009 9:44 am

With the correct mounts and arms, it should all fit fine. It is still reasonably tight down there, and I doubt you will get anywhere near 25mm of clearance.

From memory, I probably have 10mm, and have never had any issues with rubbing.

Ian.
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SAE30
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Post Wed May 06, 2009 11:41 am

ian332isport wrote:With the correct mounts and arms, it should all fit fine. It is still reasonably tight down there, and I doubt you will get anywhere near 25mm of clearance.

From memory, I probably have 10mm, and have never had any issues with rubbing.

Ian.
Thanks again Ian, im gonna fit the e36 arms with the 535 rubber mounts (long cylinder shape) tomorrow, hope it fits fine, so 10mm should be fine then..
GeoffBob
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Post Wed May 06, 2009 12:34 pm

A brand new mounting will sag (compress) by about 10mm over 3 to 5 years due to the fact that the material from which it is manufactured is viscoelastic. That's why I suggested 25mm clearance over the rack. If you can't manage this, then the very least you can afford is 15mm. At least then you'll have 5mm left after the mounts have compressed. Otherwise, be prepared to change mounts in few years time.
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SAE30
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Post Wed May 06, 2009 6:13 pm

Thanks, so ill aim for 25mm, if not then 15mm min... will keep you posted after tomorrow