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Discussion Starter #1 (Edited)
Hey guys,

I am installing a brand new Gen VI GM Performance zz454 into my 70 Chevy Nova. The engine that was in it before was a Gen IV 454 old 70s truck motor. It sat back pretty far and worked in that spot. With the new frame mounts and motor mounts it has moved my engine so far up that I can't find any oil pan that will work with it. My steering rod is now hitting the sump. The pan I got was especially made for my Nova with rear steering and the thinnest sump I could find.

I used OER big Block factory frame mounts and Jegs poly engine mounts.

I need to move the engine back about 2-1/2 inches if possible. I have about 4" of space between the engine and firewall as well.

We have no idea whats going on here. We need all the help we can get please.

Here are the frame mounts I got
https://www.jegs.com/i/OER/691/K701/10002/-1

Here are the motor mounts I got
https://www.jegs.com/i/JEGS/555/61801/10002/-1

Here is the pan I got
https://www.summitracing.com/parts/mor-20413/overview/

20190501_144322_fx by ssnovass396, on Flickr
20190501_144316_fx by ssnovass396, on Flickr
20190501_144131_fx by ssnovass396, on Flickr
 

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I went through the same questions on here with my Gen IV 454 swap. I used the GM oil pan that was in my 67 Impala. It hugs the subframe and just clears the rear steering. Used K701 frame stands and T82283 motor mounts. I found the following article that answered a few of my concerns about the motor positioning.

https://www.hotrod.com/articles/big-block-camaro-nova-engine-swap-guide/
Engine Mounts
Three different frame mounts were used: six-cylinder mounts, small-block (SB) mounts, and big-block (BB) mounts. Certain 1967 Camaro and 1968 Camaro/Nova mounts differ from 1969 mounts. Any of the engines physically fit any of the mounts, but the location and “angle” of the engine changes. BB frame mounts have height differences between left and right sides. They also place the engine slightly farther forward in the engine compartment and move it toward the passenger side.
This doesn’t mean that a BB won’t fit on SB frame mounts. It works, but the engine sits farther to the rear of the compartment, while the driver side of the engine sits slightly lower and farther to the driver side. This can create header issues and makes for tight firewall clearance. To gain engine setback (more rear-weight bias), you can use this system. Or to get radical, use a set of six-cylinder frame mounts, which provide even more setback. The firewall sometimes requires hammer surgery for distributor clearance, plus the bellhousing bolts become almost impossible to reach.
 

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I have a stupid question that I really don't have an answer to but are the frame mounts swapped. I thought, but i can't remember the bolt holes would not allow that? I really cannot see it being a pan or motor mount issue especially with 4" to the firewall. We all wish we had that kind of space.
 

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Where did you position your engine mounts on the crossmember?
Are the engine mounts on the new engine block located in the same place as your old block?

I suspect you haven’t positioned the mounts on the crossmember in the correct set of holes for this engine. If the mounts are located differently on this block then the previous engine and the crossmember mounts are where they should be then you may have to determine whether you can reposition the crossmember mounts to accommodate the set back you need or possibly get some adjustable offset engine mounting adapters to put the engine where you want it.

I would take some measurements of the old and new engine blocks to varify whether or not the engine mounts are located in the same position. Measure from the bell housing flange to the engine block mounting bolts.. If they are the same then the crossmember mounts aren’t set in the correct locations. If they are different then by how much and then you’ll have to determine if you can reposition the crossmember mounts to put the engine in the correct position. If the crossmember mounts can’t be repositioned to correct the engines placement then adjustable mounts are going to be the solution..
 

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Discussion Starter #5 (Edited)
I went through the same questions on here with my Gen IV 454 swap. I used the GM oil pan that was in my 67 Impala. It hugs the subframe and just clears the rear steering. Used K701 frame stands and T82283 motor mounts. I found the following article that answered a few of my concerns about the motor positioning.

https://www.hotrod.com/articles/big-block-camaro-nova-engine-swap-guide/
Engine Mounts
Three different frame mounts were used: six-cylinder mounts, small-block (SB) mounts, and big-block (BB) mounts. Certain 1967 Camaro and 1968 Camaro/Nova mounts differ from 1969 mounts. Any of the engines physically fit any of the mounts, but the location and “angle” of the engine changes. BB frame mounts have height differences between left and right sides. They also place the engine slightly farther forward in the engine compartment and move it toward the passenger side.
This doesn’t mean that a BB won’t fit on SB frame mounts. It works, but the engine sits farther to the rear of the compartment, while the driver side of the engine sits slightly lower and farther to the driver side. This can create header issues and makes for tight firewall clearance. To gain engine setback (more rear-weight bias), you can use this system. Or to get radical, use a set of six-cylinder frame mounts, which provide even more setback. The firewall sometimes requires hammer surgery for distributor clearance, plus the bellhousing bolts become almost impossible to reach.
Mike, thank you for jumping in here. I am reading that article right now and one thing I noticed was that it said the BB frame mounts move the engine over to the passenger side more. On the contrary it didn't seem to move the engine over at all and if anything moved it over toward the driver side. That is why I am wondering if we put the motor mounts in backwards. Is that even possible. The mount on the driver side is the shorter one from what I can tell in the pictures and the taller one is on the passenger side. There is little to no room on the driver side, but miles of room on the passenger side.

So, are these motor mounts inter changeable from one side to the next, or are they only made to fit on one side and will not fit on the other?

20190501_144304_fx by ssnovass396, on Flickr
20190501_144259_fx by ssnovass396, on Flickr
20190501_144225_fx by ssnovass396, on Flickr
20190501_144252_fx by ssnovass396, on Flickr

The pan also sits about 1/4" over the cross member with spacers. Just seems like something is not sitting right here.
 

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Discussion Starter #6
I have a stupid question that I really don't have an answer to but are the frame mounts swapped. I thought, but i can't remember the bolt holes would not allow that? I really cannot see it being a pan or motor mount issue especially with 4" to the firewall. We all wish we had that kind of space.
See my last reply. I am wondering the same question if the motor mounts can actually be swapped and maybe I have the reversed. Or do they only fit one way. I am not sure. If they could be switch, that would give me another inch or so moving it back and would also push it away from the driver side giving me more room for header clearance around the power steering box.

Does someone know the answer to this question?
 

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Discussion Starter #7
Where did you position your engine mounts on the crossmember?
Are the engine mounts on the new engine block located in the same place as your old block?

I suspect you haven’t positioned the mounts on the crossmember in the correct set of holes for this engine. If the mounts are located differently on this block then the previous engine and the crossmember mounts are where they should be then you may have to determine whether you can reposition the crossmember mounts to accommodate the set back you need or possibly get some adjustable offset engine mounting adapters to put the engine where you want it.

I would take some measurements of the old and new engine blocks to varify whether or not the engine mounts are located in the same position. Measure from the bell housing flange to the engine block mounting bolts.. If they are the same then the crossmember mounts aren’t set in the correct locations. If they are different then by how much and then you’ll have to determine if you can reposition the crossmember mounts to put the engine in the correct position. If the crossmember mounts can’t be repositioned to correct the engines placement then adjustable mounts are going to be the solution..
He placed the frame mounts in the only place it would allow on the cross member like this.

20190326_150103 by ssnovass396, on Flickr

The old frame mounts were the clam shell style and definitely not correct. The owner before me welded and made his own position with the frame mounts hanging partly off. You can see how he offset it to be further back.

20190321_135455_fx by ssnovass396, on Flickr

As far as checking this on the old engine, I don't have it anymore.

What adjustable mounts would you recommend. I saw these, but am very new to this modification and stupid expensive for what I am having to do here. Those plates will allow the engine to move back 1-1/2 inches.

https://www.dirtydingo.com/shop/product_info.php?products_id=1363

Do you know of other options? I see a lot for LS swaps, but this was the only one I could find for Chevy big blocks.
 

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Looks to me like you have your frame mounts in the wrong places driver and passenger sides are reversed. I don’t know if that is going to be enough clearance though. It’ll be close..

If you look at your pictures you see that the tall engine mount is on the passenger side and the short mount is on the driver side.. The mounts are also offset and should put the engine closer to the firewall. This may just be enough to clear the steering linkage..
 

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Discussion Starter #9
So guys are you seeing what I am seeing?

Did he put the frame mounts on the wrong sides? I am seeing what looks to be the taller one on the passenger side and the slightly shorter one on the driver side. Are you guys seeing this too or am I seeing things? Or does it look right and okay?

Made a video of it too. https://youtu.be/yRz90R9DPxE

20190326_150013 by ssnovass396, on Flickr
20190326_150103 by ssnovass396, on Flickr
20190326_150125 by ssnovass396, on Flickr
20190501_144304_fx by ssnovass396, on Flickr
20190501_144159_fx by ssnovass396, on Flickr
20190501_144105_fx by ssnovass396, on Flickr
20190501_144050_fx by ssnovass396, on Flickr
 

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Discussion Starter #10
Okay, now I could be talking crazy and these frame stands/mounts may not be reversible, but I did a little experiment.

In my diagram below, the black circles are where the screw holes go. The straight lines are the main center part that the engine mounts will screw into. They are centered and the screw holes are staggered. This setup is how it is now. The engine sits too low, is squished over to the driver side and sits about 2 inches too forward. See where it says "Extra Materials"? This material is currently sitting on the cross member unlike a few pictures I have seen where this extra material is hanging off the cross member.

20190502_001413_fx by ssnovass396, on Flickr

Now if I reverse these and switch them around here is now what I get. If I line up the screw holes, I literally get almost 2 inches of moving the engine back, exactly what I need to clear from my oil pan. Look at where the center of the frame mount/stand is now. Also, the extra material is hanging off of the cross member a tad.

20190502_001431_fx by ssnovass396, on Flickr

Am I on to something here or am I talking crazy? I guess the question still stands, are these mounts reversible? If that lower single screw hole is ever so slightly to the left or right, this wouldn't work, but if its in between the two screw holes above, that would make these interchangeable. What do you guys think? Anyone have some of these laying around to test?
 

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You have the mounts installed in the incorrectly your pictures... Put them in the correct driver and passenger side positions. The will indeed be hanging off the back of the crossmember and your engine will be positioned closer to the firewall.

Look at how the clamshell mounts were positioned on the crossmember. They were hanging off the back of the crossmember as well and everything fit with them installed this way. Correct..? If you look at ‘73 and later subframes they added a tab on the backside of the crossmember to pickup the overhanging frame mounts..
 

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Discussion Starter #12
You have the mounts installed in the incorrectly your pictures... Put them in the correct driver and passenger side positions. The will indeed be hanging off the back of the crossmember and your engine will be positioned closer to the firewall.

Look at how the clamshell mounts were positioned on the crossmember. They were hanging off the back of the crossmember as well and everything fit with them installed this way. Correct..? If you look at ‘73 and later subframes they added a tab on the backside of the crossmember to pickup the overhanging frame mounts..
Oh seriously, they are actually suppose to hang off the back? I saw this on a few other Nova's but wasn't 100% sure this was correct. Thanks. I will tell the mechanic to try this. I liked my little diagram which really showed me how much of an improvement it could be. We will see.
 

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The tall frame mount goes on the driver side, and as others have mentioned and they are situated at the rear of the frame. When I was questioning the position of my engine I compared the small block frame mounts to the new ones. The small block units are identical height side to side but offset the engine to the rear. The big block units are different heights (taller one to the drivers side) and don’t have a rear offset. The result is positioning the motor slightly to the passenger side and slightly forward.
I used a set of Hedman headers (68198) and had to made a fair dent to clear the 500 series steering box. Other than that, everything fit!
 

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Discussion Starter #14
It worked! How crazy is that. So now we have our answer. These frame mounts can be interchangeable and if you place them wrong everything will be screwed up. The pan now clears with ease and much more driver side header room and whole engine moved back a few inches. What a learning lesson and a day if stress.

However I do need your quick opinion. We still had to shim the mounts. He shimmed it with little pieces which worries me since it looks like it's creating a weak point instead of using a full plate. Is his shim setup okay and it won't harm the integrity of the mounts or is this actually putting stress on those bent areas and going to cause issues on down the road?
 

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Personally, I would prefer a full plate under the frame stands to shim them as needed. I would want the weight and stress load distributed over a much bigger surface area to prevent any distortion of the frame stands and crossmember.. You can use the old clamshell frame mounts as a template for the shim plates.
I presume you will resume the burnouts once this smoke machine gets back together.. :devil:
 

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Discussion Starter #17 (Edited)
This is a 74 subframe notice the mounting tabs on the back side of the crossmember..
OH wow, I learned something new here. Checked out the car today and the engine sits beautifully now. More clearance on the driver side, steering rods don't hit the pan, and everything sits just right. We still had to shim the frame mounts a bit for some reason to get the pan off the cross member.
 

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Those shims aren't ideal, but they will work just fine. They are decently thick though. If running a flat hood they may cause hood clearance issues.
 

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OH wow, I learned something new here. Checked out the car today and the engine sits beautifully now. More clearance on the driver side, steering rods don't hit the pan, and everything sits just right. We still had to shim the frame mounts a bit for some reason to get the pan off the cross member.
I had to shim 3/16" for the same reason.
 

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Raising the front, even a bit, will increase the downward angle of the tailshaft and increase the u-joint angle. This is no big deal if there is room between trans and the tunnel to raise the trans mount an equal amount.
 
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