I'm trying to install a Chevy 400 into my 86 Camaro. It had a 305. I'm trying to reuse the engine bracket and motor mounts from that engine on this 400, but the engine brackets appear to be about 1.5 inches wider than the Spohn K-member mounted engine mounts.

Do I need different mounts or brackets for this swap? Or do I just have something wrong?

Looks kinda like you have the frame sides turned around backwards.

The 400 is the same outer dimensions as any other SBC. No reason it shouldn't fit exactly the same as a 305.

Your second pic shows it: Your black ( polygraphite? ) inserts are flipped.

Hmm... I tried flipping the frame mount inserts, but that was clearly not the fix. The mounts were almost horizontal when I did that during test fitting in the bracket.

So I switched them back and decided I'd attach the mounts to the bracket and set it down on the K-member. The driver side lined up perfectly, but the passenger side is off my about an inch, maybe a little more.

BTW, this whole setup is new... engine, K-member, etc, so I don't know if it's the engine, brackets, mounts, or K-member that's wrong.

At this point I think I'm going to have to fab up a solid mount in order to make this work unless someone has another suggestion.

Thanks!

I really apologize if my typo caused you extra work. Slipped, not flipped.
Look, remove both pads from the K, then bolt the pads to the shells, then set the whole assembly on the K. From there you should be able to start aligning the bolt holes of the pads with the holes in the K.

Your terminology is a little confusing, but I think that's exactly what I did.

The the part bolted to the K-member is the mount, and the part bolted to the engine is the engine mount bracket. And for clarity's sake, the "insert" I'll call the bushing.

I placed the bushing into the mount and attached that to the bracket which was bolted to the engine. I then lowered the engine, bracket, mount and all, onto the K-member. The driver side lined up perfectly, and I was able to get bolts through the mount and K-member (see picture 1). The passenger side mount is now sitting about 1 inch higher than the bolt holes in the K-member (see pictures 2 and 3), and no amount of fidgeting with it got it any closer.

Are you suggesting that I swap the mount (bolted to the K-member) or swap the bracket (bolted to the engine)?

Go back to the first pics. It looks like the bushings have slipped down, like they should slide back up about 1/4" each. Further, it looks like if they were up, then the holes in the bushings would be directly beneath the holes in the shells. (The whole world has always called the block brackets "clamshells")
However, those little tabs coming out the sides of the bushings bay not let the shells drop vertically, so bolting the bushings into the shells first should solve that.

Forgive my ignorance... I thought the "clamshells" referred to the mount side only, since it opens kinda like a clam when you replace the bushing.

That 1/4" you see is an optical illusion. The polyurethane bushings completely fill the mount. That said, it does give me an idea. I could shave 1/2" off both outside edges of the polyurethane bushings which may give me my needed clearance.

Oh I see. Yeah, it could be seen that way. But until 5, maybe 10 years ago at most, noone ever drilled the rivets to open the pads. Because poly inserts did not exist.
I've never tried replacing the rubber with poly, I just keep ordering the Moroso solid mounts. But I have had a large variety of problems with installing the rubber mounts. I guess that's why I'm addicted to the Morosos.

If solid mounts are they way to go, and someone makes a set that works for this application, I'll consider it.

But I'm concerned that the K-member is incorrect. If the stock mounts don't line up, then the aftermarket mounts aren't likely to line up either.

Do you know what the measurement should be from bolt hole to bolt hole on the K-member mounts? I measure 16.5 inches.

I don't have an engine in my '84 Camaro right now, I can measure the stock spacing in a few minutes, if the rain lets up. Otherwise it'll be in the morning.

Okay, I measured. Between the lowest edges of the lower rear holes for V8 mounting, I get 14.5".
If you're wanting the spacing between the centers of the 2 big motor mount bolts, I can't provide that, sorry.

My k-member is 14" lower rear bolt to bolt. That accounts for 7/10th or so difference in the mount position. I think i just got a bad k-member.

Either way it look like I'm doing some fab work.

Thanks!