[dogboy]

My uncle works at a bone yard and just got in a old pontiac GP 67-8

he's claiming that it has a 428 engine?
it has 670 heads stamping

My donor engine also is out of a 67 grand prix
but mine is a 400 with 670 heads

The number he gave me off of the engine was XJ 0198 from what he could read. Anyone know what this is or know of a decoder web page?\


Thanks

[OINK 1]

On the back of the block is a cast in like 7 digit #
What is it?
428's only have 2 motor mount holes on each side.
Some 428's have 428 cast in on the side of the block by the freeze plugs.

Pontiac Gregg

[gtocrazy]

Dogboy,
According to www.wallaceracing.com there is a 67 "XJ" code 400 that came with 670 heads. It came in a GP. It is also a 400. The block casting number on the rear can tell you if it is a 428.

[screamingchief]

If it is a large journal motor it'll have the "transfer lug".

This is the little pyramid like projection on the passenger side above the bellhousing face of the block.

Pic from HPP.

[WDCreech]

In 67 an XJ was a 350 hp 400. No XJ in 68, but in 69, it was a 360 hp 428, two bolt main 428 w/360 hp. Best bet is to get the date code from the distributor area to see what year it really is.

[judge_jury_executioner_69]

when i got my GTO i wanted to decode the block to find out if it was numbers matching, what size the motor was, and all that good stuff. but the casting numbers by the dist were the same for the 428 and 400. but since it has a 428 cast between the freeze plugs that said it all. i thought all the 428' s had the 428 cast between the freeze plugs ? i could be wrong.

[Shadowjack]

A '67 400 block is casting 9786133. A '67 428 block is 9786135. Easy to misread, but different.

[quick67bird]

On the back of my 455 there is no Year cast by the distributor. Is that common or could it have been a replacement block?

Robert

[WDCreech]

Robert, I think that the factory only cast the big "year no." if the block was cast sometime in the year previous to the model year it was to be used. Your casting date should start with an A thru F. If it were a G thru L it would have the next model year date cast in big numerals. Note that I said "I think", so let me know if your casting date starts with a letter later than F.