mid mounts
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Race Director
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mid mounts..not another rolm thread
I thought this would be a nice thing to build. I think I've seen someone build something like this before (clutchdust, you??)
Still needs to get coated and I only welded 1 bracket to the frame on the bushing side, still need another one but need to remove the engine for that first so I'll do that later. Hopefully this simple mount will help a bit w/ my goal of eliminating the frame flex & to keep the engine from ripping off the poly mounts since I don't have room for a lot of engine movement w/ the turbos close and other stuff. If the poly bushings flex too much I will have to swap to solid engine mounts and nylon mid mounts, leaving the poly trans mount. How about my bubba fix for the dipstick
thing didn't clear the turbo stuff properly and I had to bend it. The dipstick hole will be plugged anyway when I swap to the dry sump stuff.
The mount is made from a urethane bushing I don't use (trailing arm bushin), the bushing is milled down a bit to slip snug into the tubing, then the rest is just welded to that.
Still needs to get coated and I only welded 1 bracket to the frame on the bushing side, still need another one but need to remove the engine for that first so I'll do that later. Hopefully this simple mount will help a bit w/ my goal of eliminating the frame flex & to keep the engine from ripping off the poly mounts since I don't have room for a lot of engine movement w/ the turbos close and other stuff. If the poly bushings flex too much I will have to swap to solid engine mounts and nylon mid mounts, leaving the poly trans mount. How about my bubba fix for the dipstick
thing didn't clear the turbo stuff properly and I had to bend it. The dipstick hole will be plugged anyway when I swap to the dry sump stuff.The mount is made from a urethane bushing I don't use (trailing arm bushin), the bushing is milled down a bit to slip snug into the tubing, then the rest is just welded to that.
Last edited by Twin_Turbo; Aug 13, 2004 at 01:56 PM.
Le Mans Master
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From: Brazos TX
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Loonking good, TT. You don't have a lot of room in there, do you? I think a mid plate stiffener is a great idea. Anything to help reduce the flex in the frame is good. Here is Clutchdust's stiffener. It is similar but he doesn't have the constraint of your intercoolers. I think tying into the bottom of the bellhousing is also a good idea.
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The intercoolers sit on the frame rail, the downpipe is what is limiting the amount of space there. I can't uyse the bottom of my bellhousing, the dry sump pan wouldn't fit and it's magnesium. I think the sides will work fine. I feel that strapping the sides will have more effect on engine movement than the bottom of the bellhousing. The bottom of the BH is the only part not bolted to the engine, that would make it the weakest part (and oon mine there are no bolt holes there), the sides thread into the engine, giving it a much firmer foundation.
Also, the mount is not yet finished, a 2nd bar will run nearly straight to the frame (parrallel to the firewall) and connect to a 2nd bushing but I'll have to pull the body again to finish that.
Also, the mount is not yet finished, a 2nd bar will run nearly straight to the frame (parrallel to the firewall) and connect to a 2nd bushing but I'll have to pull the body again to finish that.
Last edited by Twin_Turbo; Aug 13, 2004 at 01:41 PM.
Le Mans Master
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From: I can walk to MA
Sweet !!
Keep thinking of stuff to do, so I can catch up.
I'm glad you posted this after I got the frame all painted up.
That's one less thing to consider (not that I'd need it with my L48).
Someday, she will have a 454, though. Maybe then.
Keep thinking of stuff to do, so I can catch up.
I'm glad you posted this after I got the frame all painted up.
That's one less thing to consider (not that I'd need it with my L48).
Someday, she will have a 454, though. Maybe then.
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To illustrate, here's a very bad photoshop of how it will end up, triangulated. the blue represents the bars, the red on the bellhousing the mounting plate and the red on the frame represents the poly bushings
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From: Waterloo ontario Canada
To me is seems backwards, the engine torques to the right and yet your mount is on the right preventing torque? You want the rods to be in tension, compression bends things and you are relying on the rods regidity.
If the rods are on the drivers side they are under tension so even a light less rigid rod would work.
I had the thought that maybe the mount was very low and the motor pivots around the motor mount putting the torque arm in tension but you have it mounted high so once agian it is in compression and subject to flexing/bending.
You also have me rethinking about maybe going to solid mounts, My motor really torques over, you can see the blower really pulling/torquing to the right.
If the rods are on the drivers side they are under tension so even a light less rigid rod would work.
I had the thought that maybe the mount was very low and the motor pivots around the motor mount putting the torque arm in tension but you have it mounted high so once agian it is in compression and subject to flexing/bending.
You also have me rethinking about maybe going to solid mounts, My motor really torques over, you can see the blower really pulling/torquing to the right.
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From: NC,USA
The old school fix for breaking motor mounts... is to take a piece of chain, and bolt it to the alternator bracket bolt, and bolt the other end down to the upper A arm mounts.
Dont know about on a C3... but I see alot of that around here! Mostly on older rods, not so much on the steel mounted/poly mounted motors though!
(It prevents the motor from being able to torque to the right. Stops hoods from popping, and rubber moutns from tearing.
Dont know about on a C3... but I see alot of that around here! Mostly on older rods, not so much on the steel mounted/poly mounted motors though!
(It prevents the motor from being able to torque to the right. Stops hoods from popping, and rubber moutns from tearing.
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Thread Starter
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Originally Posted by norvalwilhelm
To me is seems backwards, the engine torques to the right and yet your mount is on the right preventing torque? You want the rods to be in tension, compression bends things and you are relying on the rods regidity.
If the rods are on the drivers side they are under tension so even a light less rigid rod would work.
I had the thought that maybe the mount was very low and the motor pivots around the motor mount putting the torque arm in tension but you have it mounted high so once agian it is in compression and subject to flexing/bending.
You also have me rethinking about maybe going to solid mounts, My motor really torques over, you can see the blower really pulling/torquing to the right.
If the rods are on the drivers side they are under tension so even a light less rigid rod would work.
I had the thought that maybe the mount was very low and the motor pivots around the motor mount putting the torque arm in tension but you have it mounted high so once agian it is in compression and subject to flexing/bending.
You also have me rethinking about maybe going to solid mounts, My motor really torques over, you can see the blower really pulling/torquing to the right.
But that one is a tad more difficult as the bellhousing plate has a hole in it for the oil temp sender wiring (it's dead ahead of it in my turbo feed line T)
Last edited by Twin_Turbo; Aug 14, 2004 at 12:54 AM.
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From: Waterloo ontario Canada
Originally Posted by Twin_Turbo
yoohoo Norval
Sunday was a busy day and I didn't spend much time on the forum.
I am not a fan of the mid mounts. It bothers me putting stress on other parts of the block. When I torque plate honed the block I had the motor mounts torqued into place already. Adding a new loading point bothers me.
I also don't want the clutter of extra bars. To be really affective in preventing flex all mounts would have to be solid, not flexable.
I can see the problem with the engine torquing over, I Have that room but hate watching the blower trying to twist off, my poor engine mounts. Lucky I have lots of room to the right.
A roll cage is really the way to go but again I don't want to limit the vet and it's removable body with a welded in cage. The mustang has a 3 point and it really makes a difference.
I like tieing the A arm towers together but I will pass on the mid mounts.
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I am still working on the roll cage, damn thing still hasn't been shipped. Don't care about removable body or not, I'm not planning on pulling the thing apart again after I'm done.
As for putting loads on other areas, early cars used the front mounts, the side mounts were used later. I prefer the front (& rear) mounts because they don't put a load on the sidewall of the block, which is just that a wall with no itnernal bracing. I'd love to have a front motor plate also but with all the junk hanging off my engine it'll be way too difficult to fab.
I'm gonna tie the a arm towers together but not with the usual spreader bar, it'll be a tad different. Still gotta buy some more steel (price went up again, thanks chinese!) and I need a bunch of 5/8 heims since Im only have 1/2 and 3/4 ones.
I also started on the rear but will have to puill the body again to finish this thing (need to bend some new round stock bars to go over the diff)
that's the beginnings of the 6 link.
As for putting loads on other areas, early cars used the front mounts, the side mounts were used later. I prefer the front (& rear) mounts because they don't put a load on the sidewall of the block, which is just that a wall with no itnernal bracing. I'd love to have a front motor plate also but with all the junk hanging off my engine it'll be way too difficult to fab.
I'm gonna tie the a arm towers together but not with the usual spreader bar, it'll be a tad different. Still gotta buy some more steel (price went up again, thanks chinese!) and I need a bunch of 5/8 heims since Im only have 1/2 and 3/4 ones.
I also started on the rear but will have to puill the body again to finish this thing (need to bend some new round stock bars to go over the diff)
that's the beginnings of the 6 link.
Last edited by Twin_Turbo; Aug 16, 2004 at 11:56 AM.
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From: Waterloo ontario Canada
Sounds like you are buying a roll cage. I have a good pipe bender and can bend 1 5/8th tubing without a problem. It is hydraulic. I never trust having to remove the frame for some reason and hate to have a future problem.
My wife also hates the cages, anyway hates the one in the mustang and it is less cramped then in the corvette.
I make mine of stainless for the mustang because I can polish it afterwards and I like working with stainless.
My wife also hates the cages, anyway hates the one in the mustang and it is less cramped then in the corvette.
I make mine of stainless for the mustang because I can polish it afterwards and I like working with stainless.
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I can not get a good pipe bender here, there are hydraulic ones but they all use a ram that pushes on the inside, collapsing the pipe. I want one that pulls over rollers but can't find one. And the cage was cheap
I don't care if it's craped, it's not like it will be a comfortable ride anyway. I want stiffness, ff the comfort.
What kind of pipe bender do you have? Not one of these right?
I don't care if it's craped, it's not like it will be a comfortable ride anyway. I want stiffness, ff the comfort.
What kind of pipe bender do you have? Not one of these right?
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From: Waterloo ontario Canada
I have one based on that pricniple but homemade. It gives wrinkle free bends on my 1 5/8's stainless tubing. Having it in the shop makes for easy custom fits.
This is not a good shot of the mustang cage but it is the only one I have
It really made a difference in stiffness of the whole car.
This is not a good shot of the mustang cage but it is the only one I have
It really made a difference in stiffness of the whole car.
and the bender?
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From: Waterloo ontario Canada
Originally Posted by zwede
Norval: Aren't you too old for boomboxes? 
My hearing is not what is use to be.Twin turbo I have a digital camera but the bender is at my sons shop right now. We share tools like that. He sometimes does custom work now. The money is good.
I will try to take some pictures and post them of the cage.