I am taking the engine out of the iroc to swap another 305 in, and I am wondering if I need to change the motor mounts or not. I was looking underneath the car, and it looks like a huge PITA to remove the mounts. So my question is, how long do the mounts on our cars last? The mounts are the stock ones, and they car has 100,000 miles on it. I would like to not have to go through the hassle of changing the mounts, as long as they are fine.

 

At 25 yrs, safe to say that they've lasted as long as they need to.

Might as well just do it.

Ya think it's a hassle now??? Just wait til you get that other motor in, and THEN discover you need to swap em.

 

It will be a lot less hassle to change them now, then later. They aren't all that expensive, look at it as preventative maintenance(assuming they are still "good" at this point).

 

Id agree with them, change them while you have the engine out. I was doing some suspension upgrades too, so i didn't have nearly the fight, i just took the springs out and was able to get at the mount bolts easily. That is also an option for you, pop the ball joint and pull the springs.

 

motors mounts are 2 pieces... frame brackets and engine brackets with thru bolts that mate the two.

unless they are severely corroded the frame brackets should be fine. they are solid metal, with grade 8 nuts & bolts so you can clean them and repaint along with the k-member

the engine brackets you should change because the clam-shell design has rubber isolators that eventually dry out & crack. (like the trans mount.)

A good upgrade is energy suspension semi-solid engine brackets. The polyurethane isolator material will outlast the car.. LOL. New ARP motor mount thru bolts w/ nuts engine bracket bolts. and be done with it.

Good luck.


if you want all new parts you can use Moroso frame brackets for their solid engine mounts and energy suspension early SBC polyurethane engine mounts. All frame & engine bolt holes match but the engine mounts will not be the "clam shell" design used on 3rd gen.

I did this when I switched to a tubular k-member. semi solid mounts are nice compromise and plenty strong. I did not want solid mounts rattling my teeth loose LOL !

 

tada

 

Thanks for the advice guys, looks like I will be replacing the mounts.