This is an assembly aid, all automakers do it. Stop and think about it for a moment. Production line cars are not hand built F1 race cars, these pieces all come from different production lines, different factories, jigs, suppliers, you name it! If your going to drill out the plates or make new spacers you will need to approach it just like a builder would from scratch.

You’ll need to set up the engine, mounts, sub-frame, etc. just as it would be when bolted down and complete. Everything will need to be hand fitted and or machined so it all lines up perfectly when you re-assemble. This is nothing new; we’ve been making solid motor mounts for our own race cars for as long as I can remember, it’s the only way you can approach it or it won‘t go back together again.

The rust mark tells me two things. First off, it hasn’t moved so the stock dampers are working. Secondly, all of the mount bolts (when engine and all parts are in place ready to tighten down) will not line up dead center through all of the mounts.

 

If it was built for "settleing" the bolts would be left loose to allow the sleeve to move, they're not left lose, as a matter of fact they're tightened enough to allow no movement, as shown by the rust marks. Everyone else in this thread that has mentioned the manufacturing process are correct.

Bitterness much?


Anywho...

I never made sleeves or redrilled the mounts when I put my car back together MONTHS ago. I tightened the mount bolts to factory specs, and left it as is. However I still think on a car that sees severe drag use and high torque loads from launching consistently, making a bolt or sleeve that fits tight might be a good idea. It certainly wouldn't hurt.

- Steve

 

That’s correct Steve, not really a good mod for a daily driver but when you start looking at all the little details on the car to get 110% out of it, it would be a good thing to do.

Good luck with your future mods.

 

This is the best reply in this whole thead . The engineers at have reasons why they do things. There is no gain if you were to get a tight fit in that bolt hole. Since the Evo has an upper tranny mount, a passenger's side engine mount that both do not have any room for error, it only fits one way, figured that you do need room for error. Rubber flexes and stretches and noone knows how much or how little they will stretch and if they were to make it a perfect fit then maybe 40k miles later the mount wont line up perfectly, therefore requiring you to twist and pry the other mounts in order to get that damn bolt in. This would preload the mounts and cause more noise problems, not to mention reduced life. Leave these mounts alone.


If in fact the bolt were to slip then you had it coming since proper torque wasn't applied. The rubber will break before that damn bolt slips, trust me

 

Hondas have been done this way for years. take a 600hp fwd civic with mad wheel hp and the same style mount does not move any. On a honda the upper tranny, timing mount and rear mount are a good fit. but the torsion mounts are the same as mitsu. this has been done for years on other cars. There are kits to even fill in the gaps in the rubber on hondas but not for the hole size issue. this tells me one thing. thats its not a problem. I would holla at say dynoflash of TT one of the big power dogs. And see if they have issues with this, chances are they dont. As its been done this way forever. Now do I know why? Nope, but i dont think assy cost is the reason cause if so alot of the other mounts would be this way, and on most cars some are perfect fit others are not. Pluss you can work the sleeve to make the bolt go in even if your off a tad. My guess is its for crash issues. Also if it was a perfect fit, rust might be an issue over a few years. If you look at the frame ona car there are bends in diffrent spots for crash reasons, if they take the time to do this i doupt that the bolt issue is just something they missed.

 

We have noticed this too. VERY odd thing that they did.

We have a solution for it and have been working on it for a month or more already. We are very close to releasing a new front and rear motor mount for the EVO. This is not an insert but a complete replacement poly mount.

The engine in the EVO moves around a lot and is the cause of many torn intercooler couplings, popped off intercooler hoses, rattling exhausts etc. etc. The new mounts that we have just about finished will hold the engine in place where it is suppose to be. Even shifting should improve some with these mounts.

I hope to see product in hand very soon.

Thanks,

David Buschur
www.buschurracing.com

 

^i need some of those.can't wait to see the product finished,and price

 

We were at the machine shop and they are actually working on the mounts now. The polyurethane cannot be cut it has to be ground which is giving them an obstacle.

David Buschur
www.buschurracing.com

 

Now this sounds really good!

 

Related to topic for stiffer engine mounts from RRE:

http://www.raktron.com/misc/mt.htm

http://www.roadraceengineering.com/ecltechtips.htm

 

You can also get Ralliart Group N motor mounts which replace all four mounts.

RA171989K1 Insulator, E/G & /M Mount 02
RA197518K1 Insulator, E/G Roll (Front) 01
RA369343K1 Insulator, E/G Roll (Rear) 01

That last number is the quantity.

These are rubber of a higher durometer rather than polyurethane. I'm thinking of going with these when I replace my clutch.

 

They are pricey last time I checked though...

 

Speaking of torn coupling both coupling on the BR upper intercooler pipe were torn. Went and got the 4 ply heady duty version. I hope these won't tear either. I hope to see the new mounts soon.

 

Engine movement is a very big problem in high horsepower hondas. on racecars, the engine mounts are solid cromoly, on street cars people putting down serious times run billet engine mounts with stiffer polyurathane. through the years we have found an improvement in 60fts, shifting, and parts breakage by going with uprated mounts.

On our fwd hondas, engine movement is a huge factor in wheel hop.

 

Any news on these?