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I'm wondering about the use of motor plates for engine mounting compared to normal mounts and other options, pros and cons, etc.

Anyone running them, or have any experience with them?
 

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Motor plates are ok if ya don't mind a bit more vibration. But the pro side of it is the motor becomes an integral part of locking the chassis ( letf to right ) together. Now remember when running a plate, make sure to run a solid trans mount on the tail shaft. You don't want to cause a weak link. The other pro is you can remove the motor and the trans will stay put.





 

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I'm wondering about the use of motor plates for engine mounting compared to normal mounts and other options, pros and cons, etc.

Anyone running them, or have any experience with them?
Good topic.

I have had this same question on "my list".

I have never really thought much about it until recently. The chassis I have for the Opel was originally under a Vega that ran a SBC & turbo350 tranny.

The chassis is made to use "engine plates" instead of traditional "motor mounts". So all of the posts are of interest to me.


With this chassis having been NHRA & IHRA certified I plan NOT to change anything about it except for what needs to be changed to get the Opel's body, etc to fit.

I will "miss" the outlandish "engine setback" that the Opel was originally built with. It was quite an attention-getter. I won't miss the problems it caused with firewall design. pedal placement, etc


That's NOT to say there still might have to be some mods made to the chassis and/or engine placement. There doesn't appear to be any issues but I will not know for sure until I mate the body & chassis together and be able to get an accurate look at how the engine, tranny, firewall, seating area, etc will align with one another.

I am hoping to get in contact with the previous owner/builder of the chassis. Any help or advice I can get will surely help.
 

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John, I don't think changes to motor mounting or location will change chassis certification. As long as you don't start cutting out frame tubes.

I don't use a motor plate, but I am using solid engine mounting. There are so many solid mounting points for my front axle, rear axle, etc. that I have noises and road vibrations transferred to the chassis all the time. I don't really notice them or find them objectionable myself, but if you want your car to ride like an average daily driver I'd go with rubber or poly mounts.
 

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John, I don't think changes to motor mounting or location will change chassis certification. As long as you don't start cutting out frame tubes.

I don't use a motor plate, but I am using solid engine mounting. There are so many solid mounting points for my front axle, rear axle, etc. that I have noises and road vibrations transferred to the chassis all the time. I don't really notice them or find them objectionable myself, but if you want your car to ride like an average daily driver I'd go with rubber or poly mounts.
I really don't plan on changing a thing with the chassis. I figure the "less I mess with things" the "less I can possibly mess things up".

The Opel has solid mounts as well as a spool. There is also no carpeting or insulation anywhere so road noise & vibration is part of the experience of having a drag car on the street.
 

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Cruizer - I am running an aluminum motor plate/ steel mid plate/limiter. Make sure you use a limiter bar to prevent the motor from moving forward/back. Plates are great for twisting loads, but will bend from launching if you don't have a bar. Newtons first law -Object at rest (600#big block) tends to stay at rest while the car takes off. Bar holds that load. one limiter should be sufficient but I am running two right/left on the Plymouth because I like to overbuild things, and there will be lots of street driving so longevity is a concern. I will post some pics here for you in the next day of my setup.

Always make sure to add a spacer between crank flange and flywheel or flexplate that is the same thickness as your mid plate, to keep everything in proper relative position.

And Steve is right, it is real nice to be able to remove just the engine or trans and leave the other in place

Steve - not trying to poke a beehive, but I always thought you needed to run a rubber or poly trans mount if you are using a motor and mid plate. reason being if the chassis flexes or twists the transmission casing will break. (this is on an automatic) Maybe 4 speed is different due to iron housing? (and I certainly hope to have enough oomph under the hood to twist the chassis a bit!)
 

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Back in the day.......on the Anglia, we ran front plates and solid mounts on the scattershield but no mount under the Muncie. :confused: :):)
 

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Back in the day.......on the Anglia, we ran front plates and solid mounts on the scattershield but no mount under the Muncie. :confused: :):)
Then that might jive with my point of letting the transmission wiggle. This might be one of those things where you ask 10 people and get 10 answers. Might be (edit) different ways to do it. I'll let Steve chime in, maybe he knows something more
 

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Craig , no beehive here my friend. I should have been more clear before I wrote my pros and cons. ;) ( I ) we, are always learning...... ;) I also believe the it may even differ between brands of drivetrain. There has been some controversy and mostly around chassis design. I should be more clear. I believe in a door car with little to no cage, your chassis will flex far enough were a problem would certainly exist.
However in a ( propper ) caged car will remove the greatest amount of diagonal twist. Coupled with a motor plate I believe you could pick your tail mounts.
However back in early 2000 we built a 41 Willys with a mild cage for a customer in western Ohio who was running a big block Mopar and toqueflite. He specified NO TAIL MOUNT. He said the week link was the length of the tail shaft and he experienced cracks behind the webbing. He was addomet about this and he was a customer who brought us more of an education.
I always up for more education ;) ;) ;)
Craig, your mention of limit bars ( inertia ) is important subject also....... ;)
 

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Last evening after my post, I searched the web and found so much more info on trans mount with plate. If I were to put a number on it I would have to say 1 out of 4 do not believe running a solid trans mount with the plate. The ones who do run direct or solid mount ( even with a cage ) use more tube gusseting, which we have always been in favor of. This seems to mean I've been extremely lucky in my builds. ;) The other is the use of after market cases, which are built for more abuse.
I've had half and half, were a lot of our builds have been race car profile built to run for street use. Even with my above post I have to rethink how my next cars are built. It's never to late to rethink ! ! ;)
But now there still remains the few that say NO MOUNT and some say RUBBER MOUNT and some still suggest Poly. Seems like another part of the build we have to science out before our choices.
 

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Thanks, Good info Steve..... being I have to figure out which way to go I appreciate the time you spend investigating & posting info for us here on the GHR forum.

As I have mentioned the chassis is already setup for a SBC held in there by engine plates.

As I have also said I do not PLAN on changing anything to just change things.

BUT if I really NEED to change things around I will.

Two biggest choices I will eventually have to make that are running around in my head are.... engine plates vs traditional engine/tranny mounts .......

The other is big choice is should I change the front suspension from the low ride height with vega rack & pinion to the MORE desirable (gasser) straight front axle.

1st.....I have been told I can get the front of the Opel "higher" by playing with how I mount the body.....but...... will I be able to get it high enough??????

2nd.....Will I be content with having a "gasser styled car" without a straight axle?????

None of these choices have to be made right now or as a matter of fact not for a longtime.

Ahhhhh ..... just part of the fun...... decisions, decisions, decisions.
 

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Well John thanks for the kind words, but lets not forget that Craig raised the question on the solid or no trans tail mount which prompted me to search out more info. As times change technology dose along with ways to accomplish better builds.

Now on another note, you mentioned mounting the body to have the desired effect of the gasser with out the axle. That is fine as long as the chassis dosent hang low enough that it looks as though it was mounted improperly.
I feel you have to decide which style build you really want to fall into.
You could however build it as the chassis is now and after running the Opel when you you shut down for the winter switch to the straight axle.
Nothing saying you can't leave it that way if you decide you like it that much. Either way it will be a very cool build.
But the one thing for sure is head on into the build, you have lots to do and the axle can be a the latter part of the build. :)
 

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Well John thanks for the kind words..............You could however build it as the chassis is now and after running the Opel when you you shut down for the winter switch to the straight axle.

Nothing saying you can't leave it that way if you decide you like it that much. Either way it will be a very cool build.

But the one thing for sure is head on into the build, you have lots to do and the axle can be a the latter part of the build. :)
Thanks for the advice...... and you are 100% RIGHT...... as much as I am a BIG "traditional style" .... built it like it was back in the days of the "gasser wars" I very well MIGHT like the later-day "gasser/pro mod looks w/o the nose-high straight axle front suspension.

As you CORRECTLY mentioned.... "one thing for sure is head on into the build, you have lots to do and the axle can be a the latter part of the build."

I am planning to disassemble what remains of the "blown-up SBC" so that all that remains in the car is the short block..... disconnect it from the tranny and then remove them separately. That way I will not have a much of a problem getting the engine out from it setback position and the tranny looks as though I can bring it up thru the floor or the interior w/o and major issues.

Hope to start on it tomorrow.

Right now the skies here a black & a storm with heavy rain is not far away.

Sounds like a good day to watch some college football......AKA put something on TV while we take a long Saturday afternoon nap!!!!! L o L
 

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I think you're past the "traditional" gasser look already John with a tube chassis, so I wouldn't worry about that. You can still build it to have the gasser look like you want, but it wont be traditional without a stock frame as required by NHRA in the day. That sure wouldn't change things for me! As I've said before, I don't get hung up on traditional, or what people think is correct. I build what I think is going to give me the most pleasure, not what's going to please others.
I like Steve's plan to get it together as it is, with the chassis tucked in to look correct. Then if you still want a straight axle later it can always be another winter project in the future. Now get out there and get started! ;)
 

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...... I like Steve's plan to get it together as it is, with the chassis tucked in to look correct. Then if you still want a straight axle later it can always be another winter project in the future. Now get out there and get started! ;)
As much as most of us won't go with anything but a traditional Straight front Axle I do think is best to go with the Opel mating with the Vega chassis.

Was taking some pics of the Opel today to show you where I'm going and what I have to work with.

Hopefully tomorrow I am going to disassemble the "remains" of the blown-up SBC that is in the Opel right now.... then yank the engine & the T350 outta there.

I am planning to take the engine & tranny out one at a time. With the engine setback and just having the short block remaining I don't think I am going to have any problems.
 

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In my Austin I am using solid mount and mid plate with a doug nash 4+1.I was told by Libertys Gears ,Richmond gears And G force Racing to use a rubber trans mount not solid not poly.They said it bind gears and break tail housings if it is solid mounted.
 
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