[Scoffey]

Hey I'm new to forums and this site . Wondering if anyone has any insight on 71 Pontiac heads 7yj .I bout an 400 in the local scrap yard to rebuild and put in my buddy's 69 tempest I'm just not sure on these heads .

[F ROCK]

Welcome to the website with the most arrogant, know it all Pontiac folks on the web.
I didn't find your heads listed as 1971 but here is a much better place to find your info http://www.wallaceracing.com/index.html
Good luck!

[Scoffey]

Its probably a 72 thinking about it p.d is dec 71 .thanks

[johnta1]

Welcome to PY!

Try this linkon head codes:

Head Code Search

A picture of the code would help. I think it is being misread.
And I agree it is probably a 1972 head.
(so use 1972 in the Year input on my link)

[track73]

It’s either a 7j2 or 7j3. 7j3 has big valves and 96 cc chambers.

[Kenth]

7J2 are 1.96" - 1.66" valves.
7K3 are 2.11" - 1.77" valves.

[Scoffey]

Yep 7 j 2

[hurryinhoosier62]

7J2s were normally found on 2 barrel equipped 400s.

[Baron Von Zeppelin]

If you plan on using headers - see if those heads have all 6 bolt holes at the exhaust ports.
Some of that vintage don't have the outermost bolt holes.
But, mods can be made to use headers - ahead of time.

The exhaust manifolds that would have been on the engine, probably won't work on an A-Body.
400 2bbl sounds like it came from a fullsize car.

[steve25]

It's a good head for a street 400 with a stock 067 Cam and high lift rockers or mild aftermarket Cam.

As posted it may not have a full compliment of Exh flange bolt holes , but there are work around for that if needed, but with a mild Cam there's no sence in running headers.

The best thing he could do is 1) mill the heads to get the compression up from 8.2 to 9 or 9.2 to 1, and 2) get the stock pressed in rocker studs yanked out and have the heads machined for screw in studs like all the Pontiac 4 bbl heads had from 1967 on up.

[Scoffey]

Engine came out of a 72 firebird . I was thing about using ram air 111 cam .I have headers on the 350 that's in the car .and th spread bore 4 bbl intake that's on the 350 .

[Baron Von Zeppelin]

Just for the sake of knowing - the only 400 available in a Firebird in 72 was the 7K3 headed 4bbl engine.
And it would have to be a Formula Bird to get that engine.

350 was the biggest engine in a regular Bird in 72.

Might not hurt to check the block code on the front passenger side of block face -
for example - YS , YD , WT , WS , etc .....
And check the casting date on the block - back by the distributor mounting hole.
K191 , AO22 , B212 , etc ...

Then cross reference that data to be sure its a transplanted 400 from another car, and not the original 350 Bird engine. They are the identical same size in exterior appearance.

A pre-71 intake is not a direct swap onto 72-later heads.
But there are work-arounds there too, i believe.

Just trying to be helpful without knowing the depth of your Pontiac background.

*also - 72 Bird exhaust manifolds will work with the 69 Tempest.
Fullsize exh mans will not work on driver side , passenger side will work though.

[Scoffey]

This is a couple #s

[Scoffey]

And a couple more

[johnta1]

The last pic shows the engine as a 1972 model from the Doraville plant.
They built the big cars - Catalina, Bonneville, Station Wagons etc.
(no Firebird for sure)


The engine code could be YX.

But a 400 is a 400 usually so it is better than a 350 IMO.

[Baron Von Zeppelin]

Pic 1 was the saving grace. Not all 400's have that cast on them.

Block was cast August 30 1971 - very early 72 production.

The block code is 2 alpha digits stamped up near where head meets block.
Area circled in Red.
Its not really going to matter now in this particular instance, but you might find it handy if you ever need to identify another engine/block in the future.


Like John said, the ''D'' in the partial VIN stamping is for Doraville, Georgia Plant.
So it was originally from a fullsize car.

[Scoffey]

So for the sake of argument. What should this engine bring used in a junkyard or swap meet ? And I will have a running 350 for sale it need a rebuild it's a 69 for sure

[Baron Von Zeppelin]

The 400 2bbl engine = $200 - 400

350 engine = hard to sale at all
Crankshaft and some external pieces have value
timing cover, pans, covers

You might do better to use the 69 heads on the 72 block
Higher Comp Ratio and Intake Manifold drops on without fuss.
Same level of heads basically on the performance scale of the castings - other than the chamber sizes.

With the 7J2 heads, about 8:1 zone CR

[Scoffey]

The heads on the 350 are 11 casting codes. And date is L 129

[Kenth]

#11 heads and L129 indicates 1970 vintage.