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So I know everyone has problems with the motor mounts on the 455 fitting correctly. Some have taken the approach to enlarge the hole to make it fit, but no one has documented how much.
Here is the set I got from Inline Tube. Notice how much the hole on the passenger side will need to be enlarged. When the passenger side is lifted, notice it is almost another hole off and there is not a lot of metal left.
Here are my qiestions
1) Is this much enlargement what everyone else is seeing with other brands? I assume there is reallly only a couple of manufacturers out there.
2) If the answer to #1 is yes, have you enlarge all on the one side or done both sides?
3) How thick is the heat sheild on the drivers side? By not having the heat shield between the block and mount, Could this move the geometry of where the engine sits to make is so as not to have to enlarge as much?
Drivers side with bolt in place, Passenger side where hole lines up closest Passenger side with engine lifted where mount is not down on frame, similar to driver side position
Troy,
One solution is to leave the mount to engine block bolts loose, This will give you some "play" to assemble the engine in the chassis. Once the through bolts are installed, you can tighten the mount to engine block bolts.
Ross
The 69 to 72 motor mounts have been problems for many years, and this is one of the reasons why the NOS mounts are so expensive. Everyone is selling mounts from the 1973 and newer cars and say they fit, but they don't without modification or having them bind. Mounts should fit without binding or modification. I ran into this problem with my W30 back in the eighties, so this problem has been around for many years. The way I cured the problem was that I installed 350 frame mounts and motor mounts on my w30, and I never had any issues. Good luck.
I've never had to enlarge these holes. Leaving the block bolts loose and the engine suspended on the hoist until the bolt are installed is the correct process as noted above. I've had to do it that way even with stock mounts back in the 1970s and 80s, so that isn't the solution. Keep in mind that there is clearance in both the holes that mount the pads to the frame and in the holes that mount the rubber mounts to the block. It isn't surprising if you tighten the bolts ahead of time, things won't line up. The mismatch you are showing is normal.
I WILL say that I have had to modify one Anchor mount, but not for this reason. One of the holes to the block was mis-drilled. A die grinder fixed that problem. Certainly not the same thing, and for $4 vs. $40, I can live with that.
I've never had to enlarge these holes. Leaving the block bolts loose and the engine suspended on the hoist until the bolt are installed is the correct process as noted above. I've had to do it that way even with stock mounts back in the 1970s and 80s, so that isn't the solution. Keep in mind that there is clearance in both the holes that mount the pads to the frame and in the holes that mount the rubber mounts to the block. It isn't surprising if you tighten the bolts ahead of time, things won't line up. The mismatch you are showing is normal.
I WILL say that I have had to modify one Anchor mount, but not for this reason. One of the holes to the block was mis-drilled. A die grinder fixed that problem. Certainly not the same thing, and for $4 vs. $40, I can live with that.
You must be lucky... I have never had a set work correct. One time I left everything loose and still had to pry and bend to get it together. After I tightened it down it bent the frame pads.
I can't remember where or how much but I have to modify them every time. I just used a set of correct NOS about three years ago and fit perfect. The problem is that you can't find NOS and when you do they are around $500 for the set.
Are these fitment problems only associated with the big block mounts? Do the small block mounts have similar fitment issues? I bought Anchor 2261 mounts for my SBO 442 but have not yet installed them.
There was commentary on another thread here where someone said that Supercars Unlimited's motor mounts were NOT Anchor brand and they claim that they fit correctly.
QUESTION: Has anyone here actually acquired a pair from Supercars Unlimited?? If so, did you make any accurate comparisons to the Anchor and/or NOS mounts??
If someone wants a good comparison then order a pair of big block Olds mounts from Supercars Unlimited AND HAVE THEM SHIPPED TO ME.
I will do a back-to-back-to-back comparison of the mounts - Supercars', NOS and Anchor.
I'll then ship the Supercars mounts to you at your expense (cheap via USPostal Parcel Post).
Then we can put a few more of these "problems" to bed.
Are these fitment problems only associated with the big block mounts? Do the small block mounts have similar fitment issues? I bought Anchor 2261 mounts for my SBO 442 but have not yet installed them.
No issues with the 350 mounts. If you are not worried about original I highly recommend using the 350 frame pads and motor mounts for your big block. It will save you the headache.
Supercars Unlimited mounts are only $22. I would be courious if anyone has ran them.
I was given a set that I was told was from there that I installed on a convertible chassis that I rebuilt for a guy. I can not confirm that is where they were from, just what he said. They fit the same as all the others. Will be interested to see the outcome of 70Post's test if someone sends him a set.
I fabbed a device that allows me to make apples-to-apples (and pretty accurate) comparisons of the mounts.......just need a pair of Supercars' supposedly "better" mounts to find out if their claim is real or not.
Remember, whoever does this will only be out the cost of shipping them from me to you (again - cheap if done via USPostal Parcel Post) after I receive them from Supercars and we can finish with the "speculation".
I used Anchor mounts on my 67 400, no problems, just keep the weight off with the hoist so you can shift the motor around some until you get the bolts through the mounts. Again a tapered punch will help to shift and align the motor.
I used Anchor mounts on my 67 400, no problems, just keep the weight off with the hoist so you can shift the motor around some until you get the bolts through the mounts. Again a tapered punch will help to shift and align the motor.
I don't think there was ever a problem with 67 to begin with?
If I'm understanding correctly, I'm not going to have this issue when I drop my '76 455 in my '71 Supreme. I just need to use my current 350 frame pads and mounts. My current mounts should still be good. They only have about 5k miles on them.
Glad I found this thread!
If I'm understanding correctly, I'm not going to have this issue when I drop my '76 455 in my '71 Supreme. I just need to use my current 350 frame pads and mounts. My current mounts should still be good. They only have about 5k miles on them.
Glad I found this thread!
You should not have a problem either on a 76. This should only be a problem from 69 to 72 A body with an Olds 455.
See below.... I was in a hurry and did not read this all the way though. You will be fine to use 350 mounts and frame pads.
Last edited by jensenracing77; August 7th, 2017 at 10:20 AM.
You should not have a problem either on a 76. This should only be a problem from 69 to 72 A body with an Olds 455.
Read it again. He's dropping a 1976 455 into a 1971 Supreme. I think your point is that this issue has only been seen with the 2328 mounts on the 69-72 frame pads. He's using 2261 on the original "small block" mounts.
Troy, One solution is to leave the mount to engine block bolts loose, This will give you some "play" to assemble the engine in the chassis. Once the through bolts are installed, you can tighten the mount to engine block bolts.
Ross
Read it again. He's dropping a 1976 455 into a 1971 Supreme. I think your point is that this issue has only been seen with the 2328 mounts on the 69-72 frame pads. He's using 2261 on the original "small block" mounts.
oops... I was in a hurry and missed that.
Macadoo, that is correct. it will be fine with the 350 frame pads and motor mounts and fit better.
I would fund Patton's project, but '68 mounts are different than the '69-72... $44 + shipping for us to know the answer forever... someone has to step up...
I fabbed a device that allows me to make apples-to-apples (and pretty accurate) comparisons of the mounts.......just need a pair of Supercars' supposedly "better" mounts to find out if their claim is real or not.
Remember, whoever does this will only be out the cost of shipping them from me to you (again - cheap if done via USPostal Parcel Post) after I receive them from Supercars and we can finish with the "speculation".
I'm in. Just saw this thread. Where do I send the payment?
No "payment" needed......just make the two Supercars mounts show up here and I'll take it from there.
And.....since you live nearby, you won't have to pay the other shipping charge to get them in your hands when I'm through......I'll just drive them over to you (uninstalled of course)
No "payment" needed......just make the two Supercars mounts show up here and I'll take it from there.
And.....since you live nearby, you won't have to pay the other shipping charge to get them in your hands when I'm through......I'll just drive them over to you (uninstalled of course)
Luke - Thanks for the offer as well.
Resurrecting this thread-Patton have you been able to compare the mounts? Are the SuperCar Unlimited mounts "better"?
I didn't even waste the time to take pics....Texas442 ordered a pair and I put my device in place (after checking it again on NOS mounts) and the Supercars mounts are NO better than any other aftermarket mount. So....they are just overpriced Anchor mounts as far as I can tell (or the same exact quality/fit made by some other manufacturer).
I didn't even waste the time to take pics....Texas442 ordered a pair and I put my device in place (after checking it again on NOS mounts) and the Supercars mounts are NO better than any other aftermarket mount. So....they are just overpriced Anchor mounts as far as I can tell (or the same exact quality/fit made by some other manufacturer).
Not worth "paying up for" IMO.
Thanks Texas442 for poneyimg up for the test mounts, and Thanks Patton for the comparison.
Since I opened up this can of worms, and already had the anchor mounts, I took others advice and left everything loose until I had the bolts in the frame pads. Then I tightened.
Not an exact comparison, but my solid Dick Miller engine mounts fit perfectly. Someone suggested having the weight of the engine supported by the hoist, that is excellent advise. You can shift the engine around until it's in the right place.
I mentioned that I had this problem back in the mid eighties with the 455 engine mount. A good friend that was heavy into 442's since the 60's indicated that the correct 455 mount was never available from the aftermarket source, therefore, he always bought GM, or changed the frame brackets to 350 type.
Not an exact comparison, but my solid Dick Miller engine mounts fit perfectly. Someone suggested having the weight of the engine supported by the hoist, that is excellent advise. You can shift the engine around until it's in the right place.
To clarify - my "concern" has not really been the "fit" of the mounts as it's obvious they can be bolted up and the motor installed, etc. My concern is more THE PLACEMENT/POSITIONING of the motor once installed with the aftermarket mounts. To me, the motor would sit a bit higher with the aftermarket mounts compared to the original mounts/positioning. That's why I started making comparisons of aftermarket mounts with originals.
I'd like parts to be back in the position the designers/engineers/etc intended them to be in.
At some point I'll probably bolt both originals and aftermarkets to a block, bolt down to the frame mounts and take some distance/clearance measurements but I have to move some stuff around and make some room first....maybe later.
Last edited by 70Post; October 27th, 2017 at 10:01 AM.
To clarify - my "concern" has not really been the "fit" of the mounts as it's obvious they can be bolted up and the motor installed, etc. My concern is more THE PLACEMENT/POSITIONING of the motor once installed with the aftermarket mounts. To me, the motor would sit a bit higher with the aftermarket mounts compared to the original mounts/positioning. That's why I started making comparisons of aftermarket mounts with originals.
I'd like parts to be back in the position the designers/engineers/etc intended them to be in.
At some point I'll probably bolt both originals and aftermarkets to a block, bolt down to the frame mounts and take some distance/clearance measurements but I have to move some stuff around and make some room first....maybe later.
It does change the engine height a little. If you run a fan shroud you may have to shim the shroud and tweak things so the fan don't hit. I have had them hit because of the mounts before.
August 6th, 2017, 03:34 AM
