User Omega

Has anyone had an issue where the pan actually touches the spring after lowering the engine? Mine very clearly touches and is actually resting on the leaf. What the???? Anyone with the shorter Hinson mounts have an idea of what kind of clearance you had?



Here you can see how much further the would need to go to seat on the mount.... UGH...

User Omega

Take a minute to use those fancy lifts boys. I want to see what others are seeing.

A side note here (I dont think it matters): My car is lowered. Could this cause the issue?

Those using these mounts: Are you stock ride height?

Johns67

MSD and Hinson short mount installed for about a month now.
No issues with cowl clearance or any other sounds.
I would think if the leaf is touching the pan I would hear it.

Just a thought, I if you are on jack stands wheels hanging the leaf might deflect upward a bit more than with it loaded.
Stock ride height.

Whis9

Get the wheels back on and sit it on the ground
Once you load springs it should clear pan, I hope...

BOTTLE FEDvette

this...when i have mine on the lift with their stander size engine mounts the spring hits the oil pan

User Omega

I just wonder how much weight is actually pressing up on the oil pan. The entire weight of this engine is on the spring right now and I would still have to tighten the nuts another 1/8" or more to get the mounts tight?

How much clearance do you have with the wheels on the ground?


Did you notice the motor weight on the spring before the engine mount before you cranked it down?

Couldn't this cause a knock sensor issue when I launch the car at the track and the front wheels unload?

User Omega

I called Hinson and they say this is normal. You have 2 choices. Add fender washers until you clear unspring or they say it is safe to install the bottom nuts in the mounts and set the car down on the ground to tighten the tops. It was advised not to tighten the mounts while the car was off the ground. I was be spacing with large fender washers. I didn't quite need the full 3/8" anyhow. Personally I wouldn't want that kind of pressure on the oil pan when the car is off the ground.

jammeejamm

that is what we did. bottom nuts first, then install the tops once back on the ground.

back on the ground it clears the pan.

ChevyCobb

Sorry in advance for my ignorance, but what are reasons for going with a shorter mount over stock other than manifold to cowl clearance?

Whis9

Clearance for our intakes

User Omega

He is correct. The only reason it was done was for intake clearance. I don't think it would actually help with anything else. I suppose it would put more weight closer to the ground but don't think it would matter.

REDZED2

I thought a dremel and an hour fixed that clearance issue. Lots run stock mounts. Funny how some have zero MSD clearance issues at the firewall cowl area and others its almost wedged. Poor tolerances perhaps. Good luck.

User Omega

That is not really not my only reason this time. I am lowering it a bit to give myself more clearance between the hood and my direct port solenoids that are mounted on my MSD intake. This will just make it all easier and can give me some wiggle room.

Dan_the_C5_Man

And I am going to install a set as a preventative measure (stock mounts have a high failure rate, especially with headers).

And I would certainly do this mod before I took a dremel to my car. Lucky for me, my MSD fit without firewall clearance issues with the stock mounts.

Glad you figured it out OP; your thread had my attention.

User Omega

Thanks Dan. I am with you. Unless I have to, I am not dremeling the car.

I made these 1/4" spacers that should get me to where the spring doesn't make contact unloaded. I milled a slot in them so I can slide them in instead of having to remove the brackets again.

Dan_the_C5_Man

Looks good.. My plan A included taking some measurements with the stock mounts in place, then potentially shimming the Hinson's to that height or possibly just slightly lower. I'm paranoid about changing the clearances of the headers to other components, reducing the clearance between the headers and the road and other potentially negative effects of lowering the engine.

Of course lowering the center of gravity of such a heavy component is all good so long as it doesn't create other problems.

User Omega

You would be in luck. Hinson actually makes an OEM height mount. That is what I took off to install this lowered version. I posted them up for sale on FB and they were gone within a couple hours. If I remember I will take a photo of how my headers and X pipe look lowered. Theoretically with the 1/4" spacer in there (2/8") I would be only lowering the car 1/8". I did not actually measure them but they look to be much more of a drop than 3/8" Look.



The buyer is picking them up Sunday so I will be able to measure them to be sure. I know for a fact that the shorter mount was a little over 61mm (2.42"). Stock height Hinson is 73mm (2.87) from what I found in a search. That would make this shorter mount damn near 1/2" shorter. If that is true then with spacers I am actually only lowering the engine 1/4".

**Some people have said that the Hinson OEM height mounts are actually slightly taller than OEM so its possible that the 3/8" shorter mount is coming down from a true OEM height? Who knows. I have no proof of that. I am just going to make it work and press forward.

Dan_the_C5_Man

Perfect, please carefully measure and post. I already knew the "stock" height Hinson's were not for me. But to the point, we really don't know the delta between an in-tact loaded stock mount vs. the shorter Hinson mount.

I will try to make a point to measure my stock, loaded mounts before I pull it apart.

outhouse

It only took a size of a dime on the firewall and not even close to all the way through. Just a little touch up. I did dremel the hell out of the MSD though.

Whis9

My Hinson mounts match this