# 1969 GTO Ram Air IV restoration



## Zap69GTO (Jan 22, 2018)

Hey everyone, I am new to the site and boy am I glad this forum exists.

I recently inherited a 1969 Pontiac GTO Ram IV. When I received the car, the engine was blown. I recently removed the engine and discovered two rods, and what appears to be pieces of a piston and cam in the oil pan. I did some research on the engine and discovered it was not the original engine block. The block was in my car was manufactured in 75’ (GM 400 V8). I am completely overwhelmed with all the options out there. What do you guys recommend doing? Start the painful process of finding a Ram Air IV engine or just throwing in something else? If so, what do you guys recommend? I am all ears and willing to explore all options. The car has a manual 4 speed transmission which appears to be in good condition and was operating just fine before the engine was blown approximately 1 year ago.

Here are the numbers on the block... not sure if I decoded it correctly.

75
A215
481988
0274675 YT

Thanks! Look forward to hearing the ideas


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## Shake-N-Bake (Jun 16, 2015)

Which cylinder heads do you have on the car? How about intake, carb, distributor and exhaust manifolds? Part numbers will be fine...we can decode the numbers for you. Do you have the PHS documents for the car? Other than the block, how close to original is the car? Any photos to post?


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## PontiacJim (Dec 29, 2012)

Zap69GTO said:


> Hey everyone, I am new to the site and boy am I glad this forum exists.
> 
> I recently inherited a 1969 Pontiac GTO Ram IV. When I received the car, the engine was blown. I recently removed the engine and discovered two rods, and what appears to be pieces of a piston and cam in the oil pan. I did some research on the engine and discovered it was not the original engine block. The block was in my car was manufactured in 75’ (GM 400 V8). I am completely overwhelmed with all the options out there. What do you guys recommend doing? Start the painful process of finding a Ram Air IV engine or just throwing in something else? If so, what do you guys recommend? I am all ears and willing to explore all options. The car has a manual 4 speed transmission which appears to be in good condition and was operating just fine before the engine was blown approximately 1 year ago.
> 
> Thanks! Look forward to hearing the ideas



Yep, the 1975 and up blocks are weak due to thinner main saddles/caps. The only good blocks were the TransAm 400 blocks which were cast like the 1974 and earlier blocks to handle the power. So you want a 1974 or earlier block. 455CI are all good. You just want to make sure the motor mounts for the block you purchase will fit your engine cradle. This has been covered before on the forums and if you do a search you can read about it just to make sure.

Here is my take. If you can afford and find a RAIV block, it still won't be the original, so what's the use unless you are trying to do a concours restoration and then, have to find a dated block that would match the build date of your car. I am assuming just the block was changed out and you still have all the RAIV top end.

So next option is that you build it to keep and have fun with it. Decide what you want out of the car - daily driver (stock specs RAIV), weekend fun(hotter cam & few go fast goodies), street/strip(bigger cubes 400CI w/stroker kit = 461 CI, roller cam, better ignition) or any combo there of. The RAIV heads stay, as would the distributor, RAIV aluminum intake, Q-jet, exhaust manifolds, ie the top end. 

Just my 2-cents.


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## Zap69GTO (Jan 22, 2018)

Shake-N-Bake said:


> Which cylinder heads do you have on the car? How about intake, carb, distributor and exhaust manifolds? Part numbers will be fine...we can decode the numbers for you. Do you have the PHS documents for the car? Other than the block, how close to original is the car? Any photos to post?


Thanks for the reply Shake-N-Bake.

Not sure what heads were on the car.

Holly Quadrajet carb

Aluminum high rise Edelbrock intake

I do have the PHS docs as well

I attached some pics for you to look at


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## Zap69GTO (Jan 22, 2018)

PontiacJim said:


> Yep, the 1975 and up blocks are weak due to thinner main saddles/caps. The only good blocks were the TransAm 400 blocks which were cast like the 1974 and earlier blocks to handle the power. So you want a 1974 or earlier block. 455CI are all good. You just want to make sure the motor mounts for the block you purchase will fit your engine cradle. This has been covered before on the forums and if you do a search you can read about it just to make sure.
> 
> Here is my take. If you can afford and find a RAIV block, it still won't be the original, so what's the use unless you are trying to do a concours restoration and then, have to find a dated block that would match the build date of your car. I am assuming just the block was changed out and you still have all the RAIV top end.
> 
> ...



Thanks for the reply PontiacJim!

Definitely just looking to re-build for weekend fun! I appreciate all the advice. I attached some photos to my earlier reply to Shake-N-Bake if you're interested.


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## Shake-N-Bake (Jun 16, 2015)

Zap69GTO said:


> Thanks for the reply Shake-N-Bake.
> 
> Not sure what heads were on the car.
> 
> ...


Looks like a fun car. Can you post a photo of the dealer invoice? You can block out the VIN if you like....just want to see what options were ordered with the car. A photo of the center two exhaust ports of the cylinder head might tell is what we need to know. Can you snap a pic of that area? 

I know of a SR RA IV block and set of cylinder heads for sale. I can send you the sellers info if you want to pursue those items...

Sent from my XT1585 using Tapatalk


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## 29585 (Aug 4, 2013)

shake-n- bake, 

this is an old thread but I am talking to a guy about a 70' SR block lately, you mentioned a SR RA iv block. How would we know its a RA iv replacement? for 1970' the 9799915 casting and SR stamping would nail it down right? Assuming the 9915 was used only for RA iv production. what about if its a 9799914 and SR stamp? That leaves it open to being a RA iii or other replacement. Please tell me your expert thoughts on this.

thanks,
chuck


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## Pinion head (Jan 3, 2015)

Originally, a "real deal" SR 979991(5) or (9799915) block casting number, was seen as a fitted 400 4bolt main block (fitted with forged TRW pistons). Once July of '70 came along, the base '70 400 9799914 casting was no more, so no more factory "wiped" last digit and correct font stamped 5. the new casting number 481988 for '71 models, had to be changed and stamped with the full 9799915 "casting" number when factory machined and assembled as a SR fitted block for previous 400 4 bolt usage.

As a real deal zone rep signed off on service replacement, a 9799915 fitted block would have been used as a warranty piece in a '70 RAIV car. Quite a few others were signed off on and used as '69 RAIV warranty fitted blocks. Many were used as SR's in non RAIV applications too, like '70 RAIII cars. Even more fitted SR 400's sat around into the 1980's at GM parts distribution centers, eventully falling into the hands of parts cleaners/vendors, racers, and collectors.


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## Shake-N-Bake (Jun 16, 2015)

clevelandpartsguy said:


> shake-n- bake,
> 
> this is an old thread but I am talking to a guy about a 70' SR block lately, you mentioned a SR RA iv block. How would we know its a RA iv replacement? for 1970' the 9799915 casting and SR stamping would nail it down right? Assuming the 9915 was used only for RA iv production. what about if its a 9799914 and SR stamp? That leaves it open to being a RA iii or other replacement. Please tell me your expert thoughts on this.
> 
> ...


I would agree with your statement if the block also has 4 bolt main caps. In my opinion, a 4 bolt block with 9799914 cast and SR stamp would originally be intended as a replacement for 1970 RA III or standard manual (WT) applications because that block would have originally be machined and fitted with cast pistons. 

If your car is a 1970 L67 and you are looking for a replacement engine block, you have several choices the way I see it. Order of preference is subjective....but my priority list would go something like this...(assuming of course the original partial VIN stamped engine is no longer available)

1. Documented 9799915 SR block. NOS, standard bore, with fitted forged pistons, dye marks, SR tag etc. New, never used.
2. Same as above, used. May require overbore.
3. Reclaimed 9799915 block from donor RA IV car. Can be documented by partial VIN and PHS docs. Would need the correct 2 letter code for your application.
4a. Undocumented 9799915 SR block. This would be a 4 bolt block with the 979991 numbers cast and the last digit ground and stamped 5 or could even have all digits ground and stamped. There is a specific font for these digits.
4b. Same as #3 with any of the remaining 2 letter codes

Opinions vary of course. The reason why I place #1 and #2 above #3 is because a documented SR block COULD be correct for ANY 1970 L67 car. Block #3 is only correct for one specific car. The application is correct for your car but since it has a partial VIN...it really is only correct for that particular car. However....the partial VIN documents it as a L67 application so it would place higher than an undocumented SR block in my opinion.

Block choices 4a and 4b are about the same in my opinion. 

I have an undocumented SR block for my 1968 L67 car. Its cast date is Dec 1969 so it was surely a 9799914 casting. That number was ground and stamped 9792506 and has an SR number. Is it correct for my application? Could be. However, it could also have been a 9799914 SR 4 bolt block intended for 1970 RA III or WT applications or maybe a 9799915 block and someone later ground off the numbers and restamped 9792506. Font looks correct but without documentation it is anyone's guess. In my case the engine came with the car when I bought it but that doesn't really prove anything since I have no documentation to validate. It would be nice if someone discovers some sort of tracking log or audit sheet for all the SR numbers for each year. If that were to happen, I suspect it would expose quite a few blocks as altered.

Sent from my SM-G930V using Tapatalk


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## bigD (Jul 21, 2016)

"...the 1975 and up blocks are weak due to thinner main saddles/caps..."

This brings a question to mind. Some online info says that some early '75 models used the older 481988 block. But, there is so much bad info, online, I was just wondering if pinion head, or anyone else has run across any '75 models which came with a 481988 block ?

Wallace Racing's Pontiac Engine Search

http://www.teufert.net/pontiac/bloccast.htm


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## Pinion head (Jan 3, 2015)

the 481988 casting 400 block continued to be used up into '75 model production. In the decade plus I had a core deal on 400's & 6X-4 heads, pulled numerous '75 usage 481988 casting short blocks. Never was able to nail down the last casting date of the '71-early '75 model 481988 block, that wasnt that important at the time. 

The one thing I did hands on narrow down during the '75 model, Pontiac 350 & 400 engines cycled from using 5C to 6X heads in Febuary of '75. In the mid 90's actually came across and pulled an original '75 Pontiac 400 with an early Feb '75 cast 5C-8 on one cyl bank and a few day later cast 6X-8 on the opposite cyl bank. The block was most likely a 500557. I pulled the 5 bolt boss (motor mount) versions of the 557 blocks early on, eventually, only pulling them for good cranks, timing covers, oil pans & timing covers.


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## bigD (Jul 21, 2016)

PH, that's good info. Thanks !


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## 29585 (Aug 4, 2013)

Thanks Shake-N-Bake ! that helps a bunch. I don't have all the info on the SR block I've been talking to the guy about, however I have seen a picture of the SR8 XXXX numbers, dont have the casting number or date. Sp I'll need to pry more info from him in order to narrow it down.
As to your preferences, I agree the #1 is the best, a documented 9915 SR block, standard bore, forged pistons, new, never used. If only I could go down to my local GM dealer with a part number and order one NOS ! LOL

If I go any further and get more info or purchase the said motor I'll fill you guys in on it here.

Thanks, Chuck


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## Shake-N-Bake (Jun 16, 2015)

clevelandpartsguy said:


> Thanks Shake-N-Bake ! that helps a bunch. I don't have all the info on the SR block I've been talking to the guy about, however I have seen a picture of the SR8 XXXX numbers, dont have the casting number or date. Sp I'll need to pry more info from him in order to narrow it down.
> As to your preferences, I agree the #1 is the best, a documented 9915 SR block, standard bore, forged pistons, new, never used. If only I could go down to my local GM dealer with a part number and order one NOS ! LOL
> 
> If I go any further and get more info or purchase the said motor I'll fill you guys in on it here.
> ...


I knew of an NOS Fitted block for sale a couple of years ago. I will try and dig up the seller's number and see if it is still available...


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## Bill E (Apr 14, 2011)

I know this post is a month old but I have a 1970 # 9799914 block running in my 68 GTO right now. It has the “68” top end on it. # 16 heads, 68 intake, 68 Q-jet. I will be installing the correct 68 YS block in winter 2019/20. The “70” block is drilled and tapped for 4- bolt mains. It’s a YD code which was a 295 HP 400 with a 2-bbl. I will be selling the #9799914 for 1500$. You can hear it run till around Thanksgiving 2019. I would also consider a trade for a complete 308 or 323 posi rear end in useable condition. I don’t know what your schedule is on your build, but this is a great motor. It pulls like a M——-F——- when you get on it. Can’t see the date code due to grime and a Pertronix dist.


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## Bill E (Apr 14, 2011)

The 1970 engine I’m talking about is a Fremont, Ca. motor if that makes any difference. I’m in the Chicagoland area.


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## PontiacJim (Dec 29, 2012)

PontiacJim said:


> Yep, the 1975 and up blocks are weak due to thinner main saddles/caps. The only good blocks were the TransAm 400 blocks which were cast like the 1974 and earlier blocks to handle the power. So you want a 1974 or earlier block. 455CI are all good. You just want to make sure the motor mounts for the block you purchase will fit your engine cradle. This has been covered before on the forums and if you do a search you can read about it just to make sure.
> 
> Here is my take. If you can afford and find a RAIV block, it still won't be the original, so what's the use unless you are trying to do a concours restoration and then, have to find a dated block that would match the build date of your car. I am assuming just the block was changed out and you still have all the RAIV top end.
> 
> ...



Wanted to follow up _AND_ correct myself for any future readers. The 481988 cast block is a good block for HP use. I am not sure when the transition took place in 1975, but you will note on the internet and other sources to steer away from the 1975 casting 500557 and up blocks. The main cap saddles have been reduced in material thickness. I enclosed a picture I got off Ebay of one of these blocks and what it looks like for easy ID. The later Trans-Am, T/A 6.6 blocks, were cast using the better 481988 castings and can be ID'd by an "XX" in the valley/lifter area as well as near the casting number on the outside of the block.


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## EddieGTO (Mar 22, 2020)

Bill E said:


> I know this post is a month old but I have a 1970 # 9799914 block running in my 68 GTO right now. It has the “68” top end on it. # 16 heads, 68 intake, 68 Q-jet. I will be installing the correct 68 YS block in winter 2019/20. The “70” block is drilled and tapped for 4- bolt mains. It’s a YD code which was a 295 HP 400 with a 2-bbl. I will be selling the #9799914 for 1500$. You can hear it run till around Thanksgiving 2019. I would also consider a trade for a complete 308 or 323 posi rear end in useable condition. I don’t know what your schedule is on your build, but this is a great motor. It pulls like a M——-F——- when you get on it. Can’t see the date code due to grime and a Pertronix dist.


Hi Bill,
Did you sell that RA IV block?
Let me know pls, 604 290 8374
Eddie


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