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Discussion Starter · #1 ·
Anyone running a motor plate for mounting their motor as opposed to motor mounts? How did you bushing the motor plate to the chassis?

We changing our motor mount set-up in the racer to a motor plate (we broke the cast mounts on the block) and I am trying to figure out all our bushing options.

Thanks
Tom
 

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Ken Blume uses a mid-plate that I made for his last buggy. It's solid mounted to the chassis. My new buggy has the motor solid mounted hanging from the front of the cylinder head mounts. Theres nothing wrong with solid mounting your motor as long as the tranny and t-case are rubber mounted.
 

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Discussion Starter · #3 ·
A shop out here told me you had to either hard mount all or bushing all... but I trust you cause your rigs flat out work!!!
 

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If you hard mount the engine, and not the rest of the stuff, you can crack tranny housings.

I chose to not use a motor plate because I didn't want to prove this again (seen it happen in drag cars).

The bad part about hard mounting everything, is if your chassis flexes, the engine/trans/tcase can't flex, and something will break.
 

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Discussion Starter · #6 ·
We dont have a choice, we have to use a motor plate, we trashed the mounts on the block (and the block is too expensive to replace). I have no problem trying to bushing the motor plate, I just need ideas on how to do that.
 

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If you hard mount the engine, and not the rest of the stuff, you can crack tranny housings.

I chose to not use a motor plate because I didn't want to prove this again (seen it happen in drag cars).

The bad part about hard mounting everything, is if your chassis flexes, the engine/trans/tcase can't flex, and something will break.
I'd like to hear Jesse's and Ken's thoughts on this. I think that the drag cars are breaking because of the amount of twist that their chassis's see. I don't think that our buggies see the same kinds of flex that a drag car does. If you make the motor plate out of aluminum it's going to flex some anyhow and then with the rest of the mounts being rubber, I'd think you'd be ok.

If you have to put bushings on your motor plate, just weld the bushing sleeve perpendicular to your motor plate and gusset it. Obviously your plate would have to be steel (heavy). I've got a design concocted in my head that you could make a bolt on bushing to an aluminum plate that wouldn't be hard to make for someone that owns/ works in a machine shop.

I wish you luck as I'm going to be doing the motor plate in my mid engine buggy w/ a northstar. I don't plan on bushing the plate.
 

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Discussion Starter · #8 ·

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I'm going to guess that guys that are breaking trannies in thier drag cars aren't running V-6's with less than 275hp. :D Yeah, I can definitely see a drag car cracking the tranny under a hard launch. Tom I know that you guys are running a pretty stout engine. Even so, you will probably be ok. If you ran the mid plate with poly bushings mounted on each side it isn't going to move much anyway. The tranny mount you have is pretty supportive too.
 

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What about running something like the bushings used on the Front Range Toyota T-case crossmember? The bolt is vertical instead of horizontal. I know this is how our motor was mounted in the dirt track car. Seemed to work ok.
 

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Discussion Starter · #11 ·
We are running roughly a 400HP/400 ft/lb torque motor. We are going to laterally suport the motor as well (recommended so a "launch" aplication, IE starting a race or jump landings) using a heim setup mounted from the chassis to the block. I am definately concerned with blowing apart the tranny or even the motor being we already trashed the motor mounts on the block. I do think we will be fine with a hard mount, I some ideas for a poly setup, but we will have to see what fits in the car.

A mid mount is out just do to their not being enough room, I spoke with Campbell Ent (where I order from, not Shannon's shop) and they said we will be fine without the mid mount.
 

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My concern would be when the frame is twisted up and the engine torque is fighting that. It could get ugly.


In a light buggy tho, it may be a moot point.

My rig is gonna be 7000 lbs + based on other similarly built rigs, and I don't want to be breaking things becasue i hard mounted something.
 

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My concern would be when the frame is twisted up and the engine torque is fighting that. It could get ugly.


In a light buggy tho, it may be a moot point.

My rig is gonna be 7000 lbs + based on other similarly built rigs, and I don't want to be breaking things becasue i hard mounted something.
You're probably right about not wanting to hard mount the motor for you application.
 

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After reading this tho I may need to look into using more than just the stock ears for the mounts. Maybe use a partial plate so the front of the block/head also sees the pull like the mounting ears.
 

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We dont have a choice, we have to use a motor plate, we trashed the mounts on the block (and the block is too expensive to replace). I have no problem trying to bushing the motor plate, I just need ideas on how to do that.
After "talking" to you in Moab, I refuse to try and help you anymore. We gave you a few people to talk to and you already had your mind made up that nothing was going to work. You had Chris Durham walk away shaking his head after talking to you.
 

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Not sure what your rig is, but I helped a buddy build a heavy rig with all solid mounts. '91 chevy k3500, rocks, 54" tires, 488 BBC 850hp/th400, divorced NP200. Engine mounted with aluminum front plate, stainless mid plate and tranny hard mounted. No problems yet.
 

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Discussion Starter · #17 ·
After "talking" to you in Moab, I refuse to try and help you anymore. We gave you a few people to talk to and you already had your mind made up that nothing was going to work. You had Chris Durham walk away shaking his head after talking to you.
Brad,

My apologies,
Moab was a disaster for us, we were running at 100 mph for nothing, the guy that built it never checked for valve clearance, the motor was fawked, all the work was for nothing and it ended up putting an exhaust valve through the cylinder wall. It was a frustrating and I am sorry if I came off the wrong way.

The car has changed a lot since Moab, it has an entirely new motor - Ford 347 and we have most of the issues worked out, and it's running really well, we just had the standard racing issues our last race and in fixing them we are looking to better the car.

Again I'm sorry if I can off the wrong way or offended anyone, that is not who I am and I'm sorry I came across in that fashion.
-----

I'm real back and forth right now-- Jesse, do you have any concerns with chassis impact harming the motor with it hard mounted. At Bad Lands after we chained the motor inplace before the last race, the car stalled everytime Lydia hit the chassis hard against a rock (granted it was stalling in a lot of other situations as well)
 

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Not sure what your rig is, but I helped a buddy build a heavy rig with all solid mounts. '91 chevy k3500, rocks, 54" tires, 488 BBC 850hp/th400, divorced NP200. Engine mounted with aluminum front plate, stainless mid plate and tranny hard mounted. No problems yet.
As long as the chassis doesn't flex, you won't have any issues, but if it flexes, the tranny will become the fuse between the engine and the tcase

if everything is hard mounted, and you get in a situation where the drivers side rear is up and the pass side is down, and the pass front is up and the rivers side down, the flex in the chassis will twist the tcase clockwise and the engine counterclockwise (as viewed from the rear)

the flex will try to rotate the engine and tcase in opposite directions, and with an aluminum housing, not many trannies could stop the rotational forces

this is especially bad when the drivetrain is long, and when a leaf srping suspension is used (as I am). 4 links tend to flex the suspesnion more than the chassis, where springs seem to flex the chassis much more
 

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Brad,

My apologies,
Moab was a disaster for us, we were running at 100 mph for nothing, the guy that built it never checked for valve clearance, the motor was fawked, all the work was for nothing and it ended up putting an exhaust valve through the cylinder wall. It was a frustrating and I am sorry if I came off the wrong way.

The car has changed a lot since Moab, it has an entirely new motor - Ford 347 and we have most of the issues worked out, and it's running really well, we just had the standard racing issues our last race and in fixing them we are looking to better the car.

Again I'm sorry if I can off the wrong way or offended anyone, that is not who I am and I'm sorry I came across in that fashion.
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I'm real back and forth right now-- Jesse, do you have any concerns with chassis impact harming the motor with it hard mounted. At Bad Lands after we chained the motor inplace before the last race, the car stalled everytime Lydia hit the chassis hard against a rock (granted it was stalling in a lot of other situations as well)
As in vibration an jarring causing issues with electronics, ect? I doubt it. There are plenty of people who have done this to thier motors in all different applications. Robby Gordons trophy truck has the engine solid mounted with a mid-plate so if it can take on the Baja 1000 it can handle Colorado Springs.
 

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As in vibration an jarring causing issues with electronics, ect? I doubt it. There are plenty of people who have done this to thier motors in all different applications. Robby Gordons trophy truck has the engine solid mounted with a mid-plate so if it can take on the Baja 1000 it can handle Colorado Springs.
That truck doesn't have to worry about chassis flex......it has a suspension that will handle all of it...most of us still have chassis flex to deal with


If you do not have the money to build a full on chassis that does not flex (which is most of us), then it may be best to not hard mount your engine/trans/tcase.
 
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