Mounts not lining up.

[Nova_Cobra64]

I tried setting my engine into the frame tonight and the motor mounts don't line up. It looks like the towers have to be moved half to one inch further apart. I never did much in depth research on this as it seemed like it would be straight forward. I'm running the towers that were on the truck with the sbc, center mount engine mounts, and moroso adapter plates.

I'm not sure if I should be hacking and welding, finding a way to adapt what is there, building from scratch, looking at buying a different setup or what would be best. On a side note, it looks like the factory ls3 exhaust manifolds aren't going to work either unless getting this mounting issue solves the clearance issue enough that they can be made to work.

The pictures I'm attaching show the driver's side mount bolted down to the tower, the other 2 show where it sits on the tower.

[Clyde65]

ur using the stock SBC mounts/perches right?

I tried that on my 65, I did get them in there but the motor sat too low IMO. You have to loosely bolt the top two bolts in and then ise a punch to line up the bottom hole. not a lot of fun. So I used the POL mounts but ECE has some that work well to.

This is what I used.

http://www.performanceonline.com/196...RACKETS-16820/

[BR3W CITY]

I had the same problem when trying to put my motor onto my stock perches. My truck was I6 that got switched to sbc (with the I6 perches on the rear holes). When I put my LS conversion plates in place and set the motor in, I was 1/2" short on room.

I decided I also wanted to move my engine forward; so I bolted the mounts an plates to the motor, then bolted the perches directly to the mounts.

With the whole thing up on the cherry picker, I set the engine into plate and used the OLD front hold as my new rear hole. I used new hardware to hold it into place, and then my mounts were welded into place.

[Nova_Cobra64]

Thanks for the info and pics. Its good to know I'm not totally SOL to make this work. I think I am going to custom build something to correct this issue, if it means chopping up the stock mounts so be it.....if it doesn't work out I won't be any further behind I figure.

Any idea how forgiving the mounting location is in these trucks before clearance issues arise? I would like to try and make use of the factory manifolds even if it means moving the engine up and back a bit.

[68GMCCustom]

I had mine on a few different mounts before I got it worked out. I started with the 6cyl perches/towers and finally went with sbc mounts. There is a a bit of flexibility in mounting...with going to electric fans solving any (too far forward) issues...only the cab restricting you how far back.

Dirty Dingo has adjustable motor mount plates.

[BR3W CITY]

BTW mine are the Transdapt plates. With my engine on those plates, SBC mounts, and the I6 perches, the engine would actually touch the firewall. Just barely, but was WAY to close for comfort. When I used the same setup but moved it forward, I was able to use the bottom bolt in place, then weld the top of the perch to the frame. That gave me enough to put the engine about 1-3/4" from the firewall, and still have PLENTY of room up front for the accessories, fan and radiator.

[68GMCCustom]

mines on Transdapt plates, sbc 1 bolt motor mounts, and sbc perches/towers in the forward holes. Plenty of room behind the motor and up front, though I am running e-fans. At some point when things get really serious () I do plan to move the motor back as far as possible.

[Nova_Cobra64]

Thanks for the input. I think the transdapt plates are the same design as the moroso. I spent a few hours playing around with engine positioning last night, swapped towers from side to side and whatnot seeing if there was going to be a simple solution. I decided I want to raise the engine about an inch and a half and set it back about an inch from the forward position. I am going to modify the top half of the towers while I am away at work and then finish the bottom half with the engine mocked up as modifying the whole thing will be difficult with nothing to test fit. I think there is a slim chance I'll be able to run the manifolds with some slight notching of the frame but I am going to get the engine in first and go from there.
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[Clyde65]

My big issue with the stock perches was getting a manifold to work with them, fbody, truck didnt work, and I didnt know about TBSS manifolds then. When I went with the POL perches and Sanderson headers it finally came together. I could have used other headers but at the time the Sanderson shorties were the only ones available for my swap.

[usmcchevy]

You can get it mounted in there. Put the stands in there with only a loose bottom bolt. Then bolt the stands to the motor loosely. After that its a matter of lifting the motor slightly and using a prybay to get the top stand bolts. Modifying the stands slightly would prabably be best though.

I used Trail Blazer SS manifolds and removed the bump from the top of the engine stand.

[Shon]

Make sure you have the plates that go on the block on the right side of the motor and pointed in the right direction
in this pic of mine they are wrong and would not work

[BR3W CITY]

As the other 2 brought up, TBSS manifolds make using the stock perches easier. Thats what I ended up using on my build.

[chevyman70]

What year are the TBSS manifolds?

[Starwood]

I had the same issue when I had to swap in a new 350 crate.

I removed the perch mounts and used a Step Drill bit to expand the holes in both the bottom perch hole and the motor mount hole.

With all the bolts loosened on the perch mount, this gave me a little extra room to find the motor mount hole nice and square. Tightened motor mount bolts first - then tightened the rest of the perch bolts.

Used extra thick/oversized washer/lock washers where holes were modified, too.

Hope this helps.

[bigmoe]

Starwood you've dug up a post from 2012, lol.

I used POL tubular frame mounts. I ended up loosening them to get the engine mounted and marking the position and lifting the motor out to redrill or ream some holes.