Big Block & Body Mount ???????

[Inthuwind]

I just put my cab on today with new body mounts and my firewall hits the left valve cover on my 396. It clears (barely) on the other side by 1/4inch. Anyone have this problem when swapping over to a big block? Any suggestions would be appreciated.

[LockDoc]

I probably can't help much but it will get your post back to the top... Did you use the big block motor mount towers that bolt to the frame? If you used the small block V-8 towers that may be your problem.... They are different.

LockDoc

[Bob Moore]

My 454 has plenty of clearance using the 72style towers and mounts. We have put BBs in probably 5 or 6 trucks without any clearance problems.

What mounts and location?

[droppedgmc]

i've got a 454 in mine...plenty of clearance

[Inthuwind]

I used the '72 towers and forward holes. I did have to notch the frame with the towers. The body mount kit I got from Mane's didn't come with instructions, but I did realize the rubber mounts were two different sizes. I swapped them around, but to no avail. My left Morosso tall valve cover hits the firewall just barely. You think I should raise the tranny some? I'll try to take some pics tonight or tomorrow, and get a better view of this. It irritates me to see it hit. It's probably something simple, but I am having brain farts. Thanks everyone.

[LockDoc]

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You don't say whether they were big block or small block towers. If they were '72 towers you shouldn't have had to notch anything, they should have bolted right up..... pictures would help a lot, with closeups of the mounts & towers.. It sounds like the front of the motor is too high which would indicate that the frame towers are small block or 6 cyl towers.

LockDoc

[clay68c10]

There's also a spacer on the trans mount for BBC trucks.

[Inthuwind]

The engine is high in the front, check the level out~the body mounts have two different rubber spacers. 1 is 1 1/4 inch and the other about 1 inch. Which one goes where front or back. Here are some pics. HEEEEEEELP~LOL

[Inthuwind]

more~

[Longhorn Man]

this isn't by chance a cut down 3/4 ton frame is it? The back of the cab *seems* lower than it should be.

[Tx Firefighter]

He's right, those are 68-71 frame stands. They are big block though. It should clear. You need the little 1/4 inch spacer between the trans and mount if you're going to use those valve covers.

[Inthuwind]

I used the thicker body mounts up front to try and raise the cab to clear----thank you for clarifying the stands. No, this is a '68 short bed frame with '72 front and rear ends. And yes, a good tip for the tranny spacer as well. Any other advice would be appreciated to get this to clear. I don't want to cut the firewall LOL!!

[LockDoc]

Originally Posted by Tx Firefighter

He's right, those are 68-71 frame stands. They are big block though. It should clear. You need the little 1/4 inch spacer between the trans and mount if you're going to use those valve covers.

I guess my question is.... Why did he have to notch the frame to get them to fit. If you look at the driverside motor mount closeup, it looks like he notched the frame 1/4"-3/8"...... It seems like something is not right there.

LockDoc

[LockDoc]

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Here are some good pictures of '72 big block mounts:

http://67-72chevytrucks.com/vboard/s...t=block+mounts

LockDoc

[Tx Firefighter]

I just went a found the pics of the 454 in my 70 truck. Here's a pic of how much room a set of stock valve covers has between the firewall and engine.



Here is a pic of where the mount and frame looked like.

[Inthuwind]

So what do I do??? I have a '68 frame and a '72 crossmember. Use a spacer on the tranny mount, and ?????????

[Bob Moore]

About the frame rail notch - I know the 67 frames were full width through that area. I know by 69 they are cut back on both sides. I had always thought the factory changed in 68 - maybe this plant had some left over and made a running change after this unit was produced. Every 67 frame I have seen has had to be notched for BB stands - either 68-71 style or 72 style.

Can the the cab be scooted to the rear just a scooch by losening the mounts and then fitting a thick washer? The tranny mount spacer (about 1/8th") might also change the angle the covers meet the firewall.

Keep us posted - Bob

[Inthuwind]

My buddy and I tried to scoot the cab back, and I also thought about grinding away a little on those mounts.

[Longhorn Man]

Something else you can do too, loosen up the bolts that hold the engine to the stands, and also the stands to the frame, and pull it all forward as far as you can... may be able to get 1/4 inch out of it.

[qksilver]

Are you going to be around Friday? I changed jobs so not working in Fayetteville anymore but have to pick up my last check. Could come by and maybe see if we can figure it out. I have a bunch of BB mounts from 68-80 so we can figure something out.
Steve

[BB72CHEVKT]

You have an 72 towers and mounts to sell?

[trkklr77]

the problem is the covers. i cant run talls either because of the body and the boster

[qksilver]

Just trying to help out a friend

[Inthuwind]

Originally Posted by trkklr77

the problem is the covers. i cant run talls either because of the body and the boster

I'm gonna make these work...somehow. Thanks everyone for the help. I'm going to add the tranny spacer, maybe two, and then try to move my engine forward. I am also going to put the thicker body mount bushing in the rear mounts to bring the cab level. I'll be dang if this thing kicks my ass.

[clay68c10]

I'd bet the trans spacer fixes it, you seem to have a lot of rearward tilt to the eng. Mine is a lot more level than that. Your level bubble should show way closer to level on top of the carb mounting surface.