# Which motor mounts for 71 Pontiac 455 HO?



## Molten (Mar 20, 2015)

Hi,
I am new to this forum and new to GTO and need some help.

The motor I got with this basket case is 1971 455 HO but chassis/frame is 68/69.
Would you guys be able to show me which engine mounts I will need on the frame and motor ?

Thanks 
Scott


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## oldskool (Apr 26, 2015)

*Mounts*

Use mounts that match the body/chassis. The '71 block will have all 5 motor mount bolt holes for either 2 or 3 bolt block mounts. 

2-bolt mounts are number 2255 & 2256 in several of the cheaper brands, like Westar, Anchor, DEA, Parts Master, etc. Online prices range from under $5 + shipping at Rock Auto, to $10 or less shipped (or more if you wanna pay more), on Ebay.

http://www.summitracing.com/parts/ani-2255/overview/year/1965/make/pontiac/model/gto

http://www.summitracing.com/parts/ani-2256/overview/year/1965/make/pontiac/model/gto

There are obviously better quality mounts available, for higher prices. For my A-body bracket cars, I always used stock type mounts and tied the driver side down with turnbuckles, from the front and rear of the head, down to the frame.

Here are some new frame brackets, for about a hundred bucks. Used will do just fine.

http://www.ebay.com/itm/64-78-Ponti...ar:1969|Model:GTO&hash=item2c65c0b25a&vxp=mtr

Some of the '70's A-bodies with the 455 engine, used 3-bolt mounts. According to Butler these 3-bolt mounts will require different frame mounts, which they sell. They also show some super mounts and even solid mounts, is you want and can afford 'em. Again, the 455 blocks will accept either kind.

http://www.jbp-pontiac.com/products/fasteners/motorMounts.htm


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## Molten (Mar 20, 2015)

Thanks Oldskool
Had a look around the parts that were with this car.
Not sure if I can use any of them with the 455.


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## Molten (Mar 20, 2015)

Here is pic of the mounts that are on the engine.

Would I then need a pair of the mounts Oldskool shown in the first links?


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## oldskool (Apr 26, 2015)

Molten said:


> Here is pic of the mounts that are on the engine.
> 
> Would I then need a pair of the mounts Oldskool shown in the first links?



Yes. Those are late '70's mounts. I think they started using them in around '75, in Birds and some larger models. The Bird mounts were slightly different than the others.


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## oldskool (Apr 26, 2015)

Molten said:


> Thanks Oldskool
> Had a look around the parts that were with this car.
> Not sure if I can use any of them with the 455.


Those 2 frame mounts, on the left are the kind used with the block mount pictured in the previous post. 

I don't recognize the 2nd one from the right as being from a '68-'69 Pontiac A-body.

http://www.ebay.com/itm/64-78-Ponti...el:GTO&hash=item2c65c0b25a&vxp=mtr&rmvSB=true


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## Molten (Mar 20, 2015)

Molten said:


> Thanks Oldskool
> Had a look around the parts that were with this car.
> Not sure if I can use any of them with the 455.


Hey Oldskool
Thanks again.Looks like the 2 mounts on left in the photo have weld on some parts of the edges. I would have thought bolts were enough.
So from what you say, I can use those 2 with the existing 3 bolt block mounts.


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## oldskool (Apr 26, 2015)

Molten said:


> Hey Oldskool
> Thanks again.Looks like the 2 mounts on left in the photo have weld on some parts of the edges. I would have thought bolts were enough.
> So from what you say, I can use those 2 with the existing 3 bolt block mounts.


NO !!! Those mounts are for 1975 and later vehicles. You need the kind that were made for the year A-body you have.

Now it might be possible to use the later mounts in the earlier cars. But there will be no holes in the frame for them. The only way you can know for sure if you can make 'em work is to bolt all 4 pieces onto the engine, and set it down in the frame. If the engine is not sitting too high or too low in the frame, I suppose you could just level the engine and tack the frame mounts in place, then pull the engine and weld them to the frame.

I tried this in a '75 Ventura. But the mounts I had were not from a Bird, so the engine sat much too high. At the time, I did not know there was a difference in the Bird mounts and the other Pontiac models. They look almost identical.

But I think in your case, it would be better to use the stock type mounts for your year A-body.


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## Molten (Mar 20, 2015)

Ok, now I think I gotcha.
So it's the ones that you put the eBay link that I need to mount to the frame and the ones at summit racing I need for the motor - yes?


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## oldskool (Apr 26, 2015)

Molten said:


> Ok, now I think I gotcha.
> So it's the ones that you put the eBay link that I need to mount to the frame and the ones at summit racing I need for the motor - yes?


All the sites I Googled says that all the '64-'69 Pontiac A-bodies used the same mounts, for V8 Pontiac engines.

Now, as I said, the cheapest mounts seem to have part numbers 2255 for one side and 2256 for the other. Westar brand has an EM prefix, and DEA brand has an A prefix. Rock Auto has the cheapest price on these which I can find. But that does not include and shipping charges. So if the mounts are all you are buying, they would probably be cheaper from a vendor with free shipping. Or, if you have a larger order from a vendor who has the mounts, you may be able to get a free ride for 'em. 

RockAuto Parts Catalog

http://www.summitracing.com/parts/ani-2255/applications/

http://www.summitracing.com/parts/ani-2256/applications/

[ame]http://www.amazon.com/Westar-EM2255-Engine-Mount/dp/B000C9765Q[/ame]

[ame]http://www.amazon.com/Westar-EM2256-Engine-Mount/dp/B000C95PM2[/ame]

[ame]http://www.amazon.com/DEA-A2255-Front-Right-Engine/dp/B0067UBVWI[/ame]

[ame]http://www.amazon.com/DEA-A2256-Front-Engine-Mount/dp/B0067UBXEO[/ame]


http://www.summitracing.com/parts/pio-602255

http://www.summitracing.com/parts/pio-602256/overview/


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## Pinion head (Jan 3, 2015)

oldskool said:


> All the sites I Googled says that all the '64-'69 Pontiac A-bodies used the same mounts, for V8 Pontiac engines.
> 
> Now, as I said, the cheapest mounts seem to have part numbers 2255 for one side and 2256 for the other. Rock Auto has the cheapest price on these which I can find. But that does not include and shipping charges. So if the mounts are all you are buying, they would probably be cheaper from a vendor with free shipping. Or, if you have a larger order from a vendor who has the mounts, you may be able to get a free ride for 'em.
> 
> RockAuto Parts Catalog


'64-72 Pontiac A-body w factory installed 326, 350, 389, and 400, all used the same "stretched triangular shaped" engine stands and the same "motor" mounts. Have several pair of the engine stands.

Unfortunately, many of the last 20 years cheap (made in China) engine mounts for this application do not hold up very well. For years have grabbed NORS engine mounts out of old parts store buyouts...being 35-40 years old, they were fine.


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## oldskool (Apr 26, 2015)

"...Unfortunately, many of the last 20 years cheap (made in China) engine mounts for this application do not hold up very well..."


Yeah, if you can afford 'em, I'd buy the high $ mounts from Butler or somebody.

Butler Performance - Pontiac Engine Mounts Poly Motors Mount


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## Molten (Mar 20, 2015)

Thanks Oldskool

I will look into this a little more and make sure I understand clearly.

Out of curiosity, what is you opinion of this 'story':
A-Body Motor Mount Thread


Thanks
Scott


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## oldskool (Apr 26, 2015)

Molten said:


> ...Out of curiosity, what is you opinion of this 'story':
> A-Body Motor Mount Thread
> 
> 
> ...



Looks like the only mount you can count on is a solid one, if you can stand the vibration. Lots of race cars run solid motor plates front and rear. But, any type of solid mounting system will obviously transmit engine vibration to the body. If you can stand it, that'll solve your problem. You can buy 'em from Butler or fab some out of stockers. 

Using the '75-'81 Bird type mounts won't be cheap, unless you already have some, or have a buddy who'll sell you some cheap. They've been listed on Ebay for over $100, for several years now. 

http://www.ebay.com/itm/1970-81-Trans-Am-301-400-455-Pontiac-Engine-Mounts-Nice-/371329899433

http://www.ebay.com/itm/75-81-Ponti...ckets-Engine-Side-496892-496893-/161692689702


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## Molten (Mar 20, 2015)

Hi Oldskool
I already have those 75-81 mounts on the motor already.
I don't fancy dealing with vibration, although that other thread mentions that vibration was only felt at idle.
I prefer a 'soft' ride so may well stick with the stock triangular frame mounts and the 'summit' (apparently crappy 'anchor' type) motor mounts.
Frame is now rolling but not complete and I want to get the engine and tranny mounted so I can get body back on frame


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## Molten (Mar 20, 2015)

Damb

Looks like the mounts I have been sent are the wrong ones. They are #2335 &2336.
The width of these are a lot wider than the frame mounts.
Does anyone know what these mounts are for?


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## Pinion head (Jan 3, 2015)

Molten said:


> Damb
> 
> Looks like the mounts I have been sent are the wrong ones. They are #2335 &2336.
> The width of these are a lot wider than the frame mounts.
> Does anyone know what these mounts are for?


You have picked up the longer "455" engine mounts used on the following Pontiacs:

-'70-73 Pontiac A body's factory equipped with 455
-'70-74 350-455 firebirds
-'73, poss '74 455 GrandPrixs
-'71-73, poss '74 Bigcars

Each of the above, though using different style frame stands, all use the same long motor mounts and long bolt.


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## Molten (Mar 20, 2015)

oldskool said:


> Use mounts that match the body/chassis. The '71 block will have all 5 motor mount bolt holes for either 2 or 3 bolt block mounts.
> 
> 2-bolt mounts are number 2255 & 2256 in several of the cheaper brands, like Westar, Anchor, DEA, Parts Master, etc. Online prices range from under $5 + shipping at Rock Auto, to $10 or less shipped (or more if you wanna pay more), on Ebay.
> 
> ...


Anyone know what the correct bolt size is for these mounts?


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