engine mounts, new engines, old car.

[Doubt_Incarnate]

Its been so long since ive been here. i'm close on my project just need a little more info. this might seem like a stupid post, but its a kinda hard to find info for the iron head fwds

My car is a gen1 1986 convertable. 2.8mpfi iron head, 4spd muncie. as expected its feeling its age so i picked up a 3.1 from a yard and went to work on it.

the old motor doesn't use dogbone mounts like the 3.1 has. in comparison the old motor has cast aluminum mount from block to chassis, and im sure youre familiar with the dog bone setup, much beefier cast iron.

i think i can use the existing aluminum mounts, but what is the advantage of the dogbones? i noticed that the gen3 blocks are different castings in where the mounts bolt to the block. if i change to the newer mounts will a 3x00 bolt in, like going from a gen2 to a gen3 in a aluminum head car? im pretty sure i can weld in some fixtures to change to the newer mounting style, if its worth the while.

[bszopi]

RE: engine mounts, new engines, old car.

Although I'm not sure if the dogbode spacing would be the same, but there are some Gen 2 and Gen 3 engines that still use the dogbone mounts. See if you can find one of those, and it might just bolt up with no problems.

[Doubt_Incarnate]

i thought all the gen2+ motored cars used dogbones. my car isnt equiped for dogbones, thats the problem. the part they bolt to above the radiator isnt there for '86, it was put in with the aluminum heads for '87. the mount bolts up to the car somewhere by the ac compressor. in fact thats the only block-to-chassis mount on the front side. the new motor, a 3.1 from a 91 GP has the dogbones that mount to the chassis over the radiator. it looks like the block will bolt up either way. i just wantknow if im better off with modifying the car for the dogbones, and if doing so will make it an easy drop in for a 3x00 later.

maybe i confused you, but most likely im retarded and didnt understand your answer.

[sharkey]

first off, what kind of car do you have???

both gen 1 and 2 fwd motors use the same locations on the block for bolting the mounts to. you will be able to bolt your mounts on your 86 right up to the 3.1l without any problems, or worrying about dogbones.

now getting into the dogbone mounts in the 87+. they use a "cradle" bolted to the block and a single mount right in the center under the oilpan (3x00 motors actualy have the mount bolted to the oilpan). the dogbones stop the motor from rocking back and forth. now in your car, you have a seperate front and rear mount, so you dont need dogbone mounts to stop the motor from rocking around.

[bszopi]

No, I misunderstood you. I was thinking your car had dogbone mounts and you had an engine without the mounts. Either way, there are Gen 2 and 3 engines that mount without the dogbones. You might look into cars like the Beretta and Cavalier for possible mounts. My Beretta doesn't have the dogbones and I know they were never came with them. I'm pretty sure the Cavy's are the same way.

[Doubt_Incarnate]

my car is a 1986 cavalier rs convertible.
so im better off with my stock mounts because they are there and they wont twist anyway (lighter aluminum anyways).

seems like a gen3 block is gonna put the car down again for a good while, since i havent had a good chance to see the differnt mountups , i didnt pull the 3.1 myself, the yard guys did. i think if i want roller crap that bad i'll just save the aggrevation and go for a bowtie block. untill then i'll just swap topends around.

Thanx for all the info its been a help.

[sharkey]

ok i for some reason thought you had a w body (with all the talk of dogbones and such).

j bodies never used upper dogbone mounts. if you are looking at a gen 3 swap, check out www.domesticcrew.com/660 , they are the authority on gen 3 swaps. there is a guy on there that makes mounts for the swap.

btw, a bit off topic, but what are you doing with the old motor??? im looking for a few parts (timing cover, complete intake) for my motor thats going into my 86 z24.

[3100 MPFI]

You said that one of your old mounts bolts up where the AC compressor bolts up too? If so, on the GEN 3 engines, that was changed up some. I tired to bolt my 88 Cutlass Supreme aluminum AC bracket to the 3100 block, and the bolt holes were off. I had to get a different bracket.

Now, a newer car with the 3x00 might have something that you can use. I know the Grand Am has a mount on the SIDE, but i Have not really looked under them. They don't have dogbones.

This weekend, I am going to Oklahoma City to help a friend do headgaskets in his Girlfirends 97 Buick Skylark with the 3100. I will take a look at how the mounts are done on that car (it does not have dogbones). Might get some answeres for you.

[Doubt_Incarnate]

Cool, there may still be hopw for future upgrades. i swear i saw dogbones in a friedns 87 Jbody, but that was a long time ago. the mtor im working on is from a W car so thats where the confusion might have come in.

sorry, as far as the old motor goes its my back up in case the new one blows up.

[3100 MPFI]

The skylark has the side brackets with the dogbone on the BOTTOM, on the side. It does not have any mount on the front.