Motor Mount Stresses

[Meph]

Hello,

 

Ive got my 1jz mounted in the 240z but Id like to try to beef up my custom motor mounts a little more than they currently are. They are basiclly the same design as outlined in the 1/2jz swap thread, but designed a little different.

 

Under Hard acceleration one mount will have to deal with compression forces higher than the other (that may or may not be in tension), with the 1jz turning the crank clockwise Id think the mount on the passanger side would receive the compression stress, can anyone confirm this? I did a little experiment with a drill and I think thats how it goes.

 

Thanks

 

Meph

[johnc]

Yes.

[rucus01]

Hello,

 

Ive got my 1jz mounted in the 240z but Id like to try to beef up my custom motor mounts a little more than they currently are. They are basiclly the same design as outlined in the 1/2jz swap thread, but designed a little different.

 

Under Hard acceleration one mount will have to deal with compression forces higher than the other (that may or may not be in tension), with the 1jz turning the crank clockwise Id think the mount on the passanger side would receive the compression stress, can anyone confirm this? I did a little experiment with a drill and I think thats how it goes.

 

Thanks

 

Meph

 

 

I took a chain and wraped it around the cross member, then put a 4 inch long bolt into the block and tightened it down with a large turnbuckle. Worked like a champ. Worked like a champ. Before that the motor would roll over so much it would pop all the header bolts.

[Goober]

LOL not thats some redneck engineering

[tonycharger72]

Under Hard acceleration one mount will have to deal with compression forces higher than the other (that may or may not be in tension), with the 1jz turning the crank clockwise Id think the mount on the passanger side would receive the compression stress, can anyone confirm this? I did a little experiment with a drill and I think thats how it goes.

 

All sixes torque right I think (passenger side for US), My old Charger used to rip up the left hand side mount, it was a straight 6 and just before I changed the engine mount for the 2nd time, I revved the engine and was amazed how much it pulled towards the right!

[DeleriousZ]

it's very unlikely that a steel mount will fail under compression unless it's very poorly made or poorly welded. tension is the one you need to worry about.

[rucus01]

All sixes torque right I think (passenger side for US), My old Charger used to rip up the left hand side mount, it was a straight 6 and just before I changed the engine mount for the 2nd time, I revved the engine and was amazed how much it pulled towards the right!

 

Almost all enginees will try and roll to the passenger side due to the clockwise rotation. The only exception would be some of the older honda motors that turned counterclockwise. The mount that almost always breaks it the one on the driver side that is being stretched. My mount was never "breaking" but the rubber bushing on the passenger side was being compressed almost 2 inches, which was enough to cause stress on headers and pop the bolts.

[tonycharger72]

Almost all enginees will try and roll to the passenger side due to the clockwise rotation. The only exception would be some of the older honda motors that turned counterclockwise. The mount that almost always breaks it the one on the driver side that is being stretched. My mount was never "breaking" but the rubber bushing on the passenger side was being compressed almost 2 inches, which was enough to cause stress on headers and pop the bolts.

 

Oh ok, thought it was more of a straight 6 thing! The mounts were rubber sandwitched between steel, the rubber was ripping, not the steel part, would have had to of been a powerful engine to break the steel apart !

[piston]

Im thinking about using energy suspension/prothane GM tranny mounts for replacement of the original 1jz/2jz mounts. make a crossmember design to fit the gm mounts with the correct angle support for the 1jz/2jz. im just not sure how strong they really are but alot of high hp gm cars run them under high torque and it seems to be doing the job. plus the mounts are cheaper compare to the original toyota mounts.

[tonycharger72]

 

Im thinking about using energy suspension/prothane GM tranny mounts for replacement of the original 1jz/2jz mounts. make a crossmember design to fit the gm mounts with the correct angle support for the 1jz/2jz. im just not sure how strong they really are but alot of high hp gm cars run them under high torque and it seems to be doing the job. plus the mounts are cheaper compare to the original toyota mounts.

 

This might be similar, as I don't know what the GM tranny mounts look like,

 

You could always do a bolt-through-bush style mount!

 

There is a fellow called PhilUk (I think) on Hybridz who has a 1jz in his 240z, there was a massive article in Zoom? magazine years ago, which documented its owner's progress!

 

Just have to make new engine mounts and tab's of the crossmember, from memory when the 1jz engine was put into PhilUk's car, they used the bolt holes for the A/C, which are further forward on the 1jz block than the original engine mounts!

 

It was done by a shop in Sydney called "Rocko's Perfmance" - he still uses similar engine mounts in most of his conversions!

 

Its a 1986-88 VL Commodore upper control arm bush and an M10 or M12 Bolt!

 

But, any solid bush would do the trick!

 

There is a pic of a trial setup I came up with for my engine!

 

http://forums.hybridz.org/showthread.php?t=112003&page=6

 

On the last page, its a bit rough and I didn't ending up going with this idea, mainly because engine removal was such a PITA, but if your looking for strength, pretty sure this would do the job!!!