Ls motor mounts that dont vibrate

[eric1967]

Are any of you using a Ls motor mount that do not vibrate when you are driving? I have Energy Suspension polyurethane mounts, but I get engine harmonics when driving about 70mph. I believe Stielow uses 4th gen Camaro mounts for this reason, but I don't think they will clear my headers. I am looking at the Chris Alston Chassisworks mounts. Does anybody have any experience with those? Here is a link.https://www.cachassisworks.com/p-1122-camaro-67-69-nova-68-74-billet-motor-mount-and-frame-adapter-set-ls-engines.aspx

Thanks Eric

[Bad94]

I have solid mounts in mine, car is smooth going down highway.
How much does the motor move when you rev it sitting still?
Sure you don't have a motor ready to come apart? Or tire not balanced? Driveshaft?

[dontlifttoshift]

Eric, the alston mounts will be worse. Are you using an energy trans mount, too. Change the trans mount to rubber if you can, that will cure most of it.

Dan is right, make sure it is RPM related and not speed related. At 70 mph, downshift and maintain speed see if it changes.

[eric1967]

It is smooth with rubber mounts but they don't last. It's not really a vibration as much as harmonics. Motor is not moving much. You can feel it just bring the motor up to cruising rpm while parked.

[eric1967]

I will try a rubber transmission mount. Dan what mounts are you using? Thanks for the help. I think some of it is I am getting older & just want things smoother & not as loud

[parsonsj]

Holley/Hooker makes a whole set of motor mount adapters. I swapped a customer's car from polyurethane to OEM rubber mounts using the Hooker setup. It made the car a lot more docile. I kinda missed the "tautness" but the customer loved the softer feel.

[Bad94]

We made our own mounts. We pushed the motor down and far back as we could.

[eric1967]

Eric, the alston mounts will be worse. Are you using an energy trans mount, too. Change the trans mount to rubber if you can, that will cure most of it.

Dan is right, make sure it is RPM related and not speed related. At 70 mph, downshift and maintain speed see if it changes.

Donny the rubber trans mount helped with the harmonics. It probably cut in half maybe even a little better than that. Thanks for the help.

[andrewb70]

For my Cougar LS swap I used the 4th gen F-body mounts and the stock rubber trans mount. There is definitely a harmonic present that is at a much lower frequency than engine or driveshaft speed and the rubber mounts do a great job of isolating them.

Andrew

[meenaggie]

My builder likes the BRP LS motor mounts. They replace the frame stands and don't require the use of the original SBC motor mounts. They come standard with poly bushings but they offer solid bushings as well. Might be worth a try. And no, I am not using them as I had the LS2 located before I took it to my builder.

115192

[T_Raven]

I've got solid mounts on the LS1 in my 89 GTA with a poly trans mount. I actually really like it. When my clutch was new and would chatter when starting from a stop, it was really annoying, but after the break in period that got a lot better.

I wonder if there are other causes being made more noticeable by the stiff poly mounts vs the rubber ones absorbing the vibrations.

[parsonsj]

My builder likes the BRP LS motor mountsThose are the very ones I replaced. The Hooker/Holley setup is much better, and the pricing is about the same.

[eldogg]

We use Prothane mounts at DSE. No vibrations at all. I would look at your drive line angle. If the vibration was in the mount it would vibrate at same RPM no matter of vehicle speed. I hope this helps.
Thanks,
Eric Evans

[PhillipM]

Those are the very ones I replaced. The Hooker/Holley setup is much better, and the pricing is about the same.

Old thread, but John do you have a link to the ones you're speaking of?

[parsonsj]

Sure!

I'd start here: https://www.holley.com/products/ls_power/engine_and_transmission_mounts/ls_engine_mounts/

Member Toddoky here is a Holley engineer and knows these mounts better than anyone. I've found him real responsive to PMs...

[PhillipM]

I now see what you mean. Those mounts use stock 4th gen isolaters. They don't list them for 64-67 A bodies. I'm sure they could be made to work though.

[andrewb70]

I now see what you mean. Those mounts use stock 4th gen isolaters. They don't list them for 64-67 A bodies. I'm sure they could be made to work though.

Phillip,

Todd is working on the 64-67 A-bodies as we speak. The Holley kit uses the same 4th gen f-body mounts that I used in my Cougar.

http://ls1tech.com/forums/conversions-hybrids/1823793-hooker-1964-67-body-ls-swap-system-preview-thread.html

Andrew

[PhillipM]

Cool thanks Andrew!

[badazz81z28]

Prothane here too, no issues. I also agree to check the driveline angle