Motor Mount - Engine Height
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Motor Mount - Engine Height
I'm putting my 68 big-block back together and I am having hood clearance issues. Does anyone know if there are motor mounts available that will seat the engine lower than its stock height? I'm not concerned about things being stock, so if there are any aftermarket products available that do this, please let me know. Thanks!
Is my vette stock?? HAHA
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IIf you change the motor height, you will effect the transmission angle and then the driveshaft to rear differential angle. Im sure someone else can explain those angles but the drive line and differential is supposed to stay in the same plane and around a 2*-3*angle or you can get vibrations.
Have you considered a drop base air cleaner and experimenting with air cleaner heights? If you have clearance above the carburetor you should be able to make it work. How much room do you have to work with?
Have you considered a drop base air cleaner and experimenting with air cleaner heights? If you have clearance above the carburetor you should be able to make it work. How much room do you have to work with?
Le Mans Master
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From: Cool Northern Michigan
You are putting things back together. So, what has changed since it was torn apart that has affected hood clearance? Different intake? Incorrect motor mounts?
You really don't want to be dropping the engine. That just introduces more issues: Fan hitting shroud. PS pump pulley, interference. Harmonic balancer too low,
etc, etc, etc.
Unless you have three deuces, a drop-base air cleaner for the std four barrel will give you the room you need. If you have the std 14 X 3 air cleaner, there are some filter cartridges that measure 2.5" or 2.75" tall but are hard to find.
You really don't want to be dropping the engine. That just introduces more issues: Fan hitting shroud. PS pump pulley, interference. Harmonic balancer too low,
etc, etc, etc.
Unless you have three deuces, a drop-base air cleaner for the std four barrel will give you the room you need. If you have the std 14 X 3 air cleaner, there are some filter cartridges that measure 2.5" or 2.75" tall but are hard to find.
Last edited by HeadsU.P.; Feb 21, 2019 at 09:30 AM.
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I have got the air cleaner as low as it will go. I actually had to shorten the vent tubes on the carburetor and they still are stuffed into the top of the air cleaner (which is a filter element type top), so I can't go any lower on that. I also have an L88 hood with a taller scoop, so no more height changes there either.
I thought there were different mounts that could have some effect on the overall height. I do realize this will affect the driveshaft angle but I did not put the mounts in on this motor and don't know what happened to the ones I originally had, which I thought may have been lower since I did have this same issue with the last motor. More details in my next response below.
Thanks again.
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You are putting things back together. So, what has changed since it was torn apart that has affected hood clearance? Different intake? Incorrect motor mounts?
You really don't want to be dropping the engine. That just introduces more issues: Fan hitting shroud. PS pump pulley, interference. Harmonic balancer too low,
etc, etc, etc.
You really don't want to be dropping the engine. That just introduces more issues: Fan hitting shroud. PS pump pulley, interference. Harmonic balancer too low,
etc, etc, etc.
It is a completely different engine (dynoed at 682HP - had to slip that in :-D) and does have a different intake on it. The prior engine had a taller intake on it also and it may just be that this new one is even higher, but I can't imagine that it's almost an inch taller. The fans are now electric, so fan height isn't a concern and no PS.
I had someone else install the motor and need to confirm what mounts he used as maybe they weren't the correct ones...
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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Can you post pics?. Especially the front of the motor for the distance below the pulleys and then the motor mounts. An L88 hood has a ton of room so theres definitely some thing going on
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Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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It's a good chance they put the wrong mounts in or in incorrectly
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Le Mans Master
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From: Cool Northern Michigan
H-m-m-m-m-m-m. That is strange. The mount itself looks alright. You just need it about a half inch higher. Looks like its sitting too low to me. Looks like vibration damper will not clear the frame if you wanted to remove it.
Who makes those mounts?
Does it look like the frame has been modified, cut on, welded, new hole drilled, etc? Maybe its the frame at fault here.
Who makes those mounts?
Does it look like the frame has been modified, cut on, welded, new hole drilled, etc? Maybe its the frame at fault here.
Last edited by HeadsU.P.; Feb 22, 2019 at 08:29 AM.
Instructor
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From: Murphy, Tx.
Something else to consider, what are the condition of the body mounts? If they are new/good, you may consider a spacer on all the body mounts.... that would effectively raise the hood height. I think someone on this forum has done this as well.
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From: SW Florida.
what is your intake and what was previous intake. i have done some measuring on a vic JR and it is essentially the same height as OE dual plane L88-etc intake. BUT, it is not angle milled with the front lowered. and this can be done to the intake. My Vic jr is going in a 24 foot Pantera. lotsa room under the hatch...
Last edited by derekderek; Feb 22, 2019 at 06:47 AM.
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That's a great idea! I'll look into that as I'm sure they probably are still the original ones.
Race Director
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actually you then need to raise the rad support the same amount or the front of the nose is low. and that will raise radiator and shroud.
Last edited by derekderek; Mar 3, 2019 at 06:55 PM.
Safety Car
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yes, add equal shims to all your body mounts will raise the body that much off the frame. but then you will have to play more with the radiator support shims to make sure the fan blades won't kiss the shroud. and adjust some shims around the front of the front clip.
but such a project is a long and frustrating weekend....
but such a project is a long and frustrating weekend....
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yes, add equal shims to all your body mounts will raise the body that much off the frame. but then you will have to play more with the radiator support shims to make sure the fan blades won't kiss the shroud. and adjust some shims around the front of the front clip.
but such a project is a long and frustrating weekend....
but such a project is a long and frustrating weekend....