# Engine code and number Question



## jay67fast (Jul 31, 2007)

I just bought a 1970 GTO coupe. The engine has been rebuilt, but it looks like it may not be the original engine. As a matter of fact, I'm wondering if it even is a Pontiac engine. I found an engine decoder on gtoalley.com and tried to match the numbers on my engine with the numbers for a 1970 Pontiac GTO. I don't even come close!!!!
According to gtoalley the engine code should be found on a machined pad on the front of the engine in front of the right bank of cylinders , right under the engine production number.O.K. There is pad on the right side of the engine with the number 0195707 and under that number, where the engine code is supposed to be is the code XF. Not only can't I find an engine code of XF, but the engine production number doesn't match anything in the decoder. 
Does anyone know what year and make engine has an XF engine code? 

Thanks for your help.
Jay67fast


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## lars (Sep 28, 2004)

First, you need to determine if you have a Pontiac engine... just look at it - Pontiacs do not look like any other engine.

The "XF" code was used to identify the following engines:

1967	326	250 HP	
1969	428	370 HP	
1970	455	370 HP	
1977	400	180 HP	
1978	301	150 HP	

You have to determine the year of the engine in order to identify it. The casting date is cast into the block at the base if the distributor.


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## 05GTO (Oct 6, 2004)

If you have problems seeing the casting date code look for the casting number, it is located behind the no. 8 cylinder on late 67 and newer pontiac motors.

67 326, casting # 9786339 
69 428 4 bolt main, Casting # 545887
70 455, casting # 9799140
77 400, casting # 568557 
I don't have the casting number for the 301

The number 0195707 is probably the last digits of the Cars VIN or the engine serial number.


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## jay67fast (Jul 31, 2007)

*Engine code and numbers*

Thanks, guys,
I"VE GOT A CONFESSION TO MAKE!!!!:  
O.K. I don't own a GTO!!!!! A good friend of mine just bought the GTO I have posted about. He wasn't sure how to get the answers he needed so I said I'd ask around. Since he's seen how easy it is to use a forum, he has decided to join himself, so I won't have to post for him. But let me finish what I started!! 
I'm a Mustang man!! I own a 67 Mustang fastback, V8, A/T, A/C, S/S deluxe interior,with all the bells and whistles. It's my fourth 67-68 Mustang I've owned over the last 25 years.I have a good working knowledge of 67-68 Mustangs, but that doesn't help me here! 
Please bear with me--- I know that Ford labels the cylinders passenger side , front to back, 1-2-3-4, and drivers side front to back, 5-6-7-8. Does Pontiac number them the same? If I need to go to the #8 cylinder, would that be the rear most cylinder on the drivers side? We're still trying to find out what engine he has in the GTO. He has the build sheet, which says the car was built with a 400 engine with A/T. At this point we're concerned that without knowing exactly what engine is in the car, he won't know what parts to ask for. 
Thanks for your help.
Jay67fast


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## 05GTO (Oct 6, 2004)

Welcome to the forum, post some pictures of your mustang. Cylinders 2,4,6 and 8 are on the passenger side, the block casting number is on a lip just below the head on the back of the block. With a flashlight I can see mine if I raise the hood and look between the cowl and the hood. 

Here is a picture;










Look for this 455 or 428 stamp on the drivers side just behind the fuel pump,


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## jay67fast (Jul 31, 2007)

Thanks for the interest in my Mustang! I can go one better than posting pictures----I have two pages of photos in a photobucket album---if you're interested , take a look--

http://s62.photobucket.com/albums/h116/jay67fast/ 


Jay


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## Rukee (Feb 8, 2007)

jay67fast said:


> I'm a Mustang man!!


That`s too bad. 

Seriously though, nice looking stang. :cheers


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## mdilello (Aug 1, 2007)

I am the owner of the car you were helping, If possible I need a little more help trying to figure out what motor I have in my 1970 GTO, following your direction Iwas able to pull a date code off the block, it is J108 (10/10/68) is that correct???? Iwas also able to locate the block casting number which was very hard to see, so using a mirror and flashlight I am pretty positive that the number is 8965616, this does not match any numbers I can find for a Pontiac engine. I also was not able to see 428 or 455 located on the block by the fuel pump, not saying its not there I just might not have been able to see it. Do any of these numbers help to identify what I have under the hood, any help would be greatly appreciated.
Thank you
Matt


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## 05GTO (Oct 6, 2004)

If you turn your casting number upside down it may be 9792968 which is for a 68 428 or a 69 400, the October 1968 casting date would be correct for the 69 model year. Verify the letter code, if it is an XP and not XF as stated above your engine will be a rare 400 Ram air IV with a 4 bolt main. This is a GTO engine!


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## POOF (Jan 16, 2007)

Jay, Nice car!! Good luck on your quest about the Goat.


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## jay67fast (Jul 31, 2007)

RUKEE and POOF,
Thanks! Actually, between Lars and 05GTO we were able to find out what engine it is. It is an XF and the number is 9792968. So, theat makes it a 69 400 (if we're right). 
Thanks again to all of you for your help.
Jay67fast


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## 05GTO (Oct 6, 2004)

Jay,

Pontiac also had a 428 in 69 with that casting number,

If the letter code is XF the engine is a 428 from a Gran Prix,
If the letter code is XP the engine is a 400 from a GTO.

A 428 is a bored 400 and most parts are interchangeable, another way to tell a 68 from a 69 is count the bolts on the water pump, 68 has 8 and 69 has 11.

Hope that helps,


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## jay67fast (Jul 31, 2007)

Randy,
Thanks a lot--really appreciate it!!! We'll keep you posted, because at some point we'll probably need more help learning about this car!!!!
Jay


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## mdilello (Aug 1, 2007)

I want to thank you for your help with figuring out what size motor is in my car, I was able to determine the engine date is J108, Engine code XF and after alot of different twists and turns that the casting # is 9792968, there is no 428 stamped on the block by the fuel pump so I`m pretty sure I have a 400 under the hood.
Thanks again,
Matt


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