shimming motor mounts

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mopardemon340

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im doing my 5.9 magnum swap in the next few months and want to make sure i have all the information i need to do it right.. what i would like to know is do i have to shim my engine to have clearance to use dougs headers .. ill be using the motor mounts off of my 340.
 
It SHOULD clear since most swap kits are designed to do so, OE mounts SHOULD work in the OE equipment, headers are designed to clear (though QC blows at 99% of the manufactures.)

What makes you think you NEED to shim the engine with "DOUGS" headers?
 
well i did a google search on doug headers on a 72 demon and there was a guy having clearance problems with his torsion bars and p/s and people where saying to shim his engine. the only mounts i have are the stock 340 mounts or should i get something else for this swap
 
IF you need a shim and you want to purchase a pack of shims, shumaucher has shims. There come in a pack of IIRC, 5 pairs on shims. I used Them on my engine swap. My tti headers hit the manual steering box.

This man be an extra unneeded expense .
 
guess ill try and get them in once im to that point. and if they dont clear i guess i have to get a shim kit.
 
i just made shims out of some scraps. I used a solid mount on the drivers side and stock passenger. passenger side needed the shims
 
^^^^ This is great advice.

All it takes is a small piece of 1/8-1/4 flat stock and cut a slot part way through it. Not tough to do at all.
 
when you use shims do you shim both sides or just one side?
 
When I ran a magnum motor, the only issue I had was the headers hit a raised, threaded boss on the block. Make sure you bolt them up on the engine stand. It was a pain grinding that when it was down in the engine bay.
 
when you use shims do you shim both sides or just one side?

Shim it however you much you need to to gain the clearance you want. I ended up giving mine 1/8" on one side and 1/4" on the other. You can level the engine by moving it side to side in the saddles if you so desire. Get it where you want it and snug the bolts down. As said, if you have some scrap laying around, make you own. I used 1/8" aluminum plate- super easy.
 
IF possible, put a level on the air cleaner and try to keep it level.
 
thank you for the help. hoping i dont need to shim but if i do i will follow the advice.
 
thank you for the help. hoping i dont need to shim but if i do i will follow the advice.

My step tube TTI's needed to be massaged to clear both torsion bars, the idler arm and inner tie rod on the passenger's side and the power steering box. I heated them up red hot in those areas and gently tapped them into shape with a ball peen hammer. Nothing worse than hearing them hit stuff while your engine is loping at idle.

To do it right may require pulling the motor and back out and putting it in to access those spots with a hammer. It is hard to do it with everything bolted up and running, but it can be done by loosening motor mounts etc. The VHT silver blends nicely with the ceramic coating for touch ups too.
 
i also made shims by my self - just some flat steel stock part, cutting a slot into it, lift the engine a bit and slide it right into it. passenger side was (as far i remember) about 6 millimeter and driverside was 10 millimeter - sorry for the metric

i also had to use shims wiht the former LAengine in order to get enough clearance for the Headers etc. (2 millimeters passenger side and 10 mm driver side)

in my opinion nothing to worry about
 
Another issue I had crop up when I shimmed my motor mounts was that it reduced my air cleaner to hood clearance enough to cause contact between the two.
 
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