Anyone know where to get the full specs for the RamAir IV engine as compared to a "regular" 400? Any block differences, or is it all on the top? I may have found one locally and am trying to decide how desirable this engine is. Also, want to varify authenticity.

'69 RAIV heads should be 722, round port.
Intake is aluminum 9796614.
Block casting 9792506, 4 bolt main.
Engine code WH for manual or XN for auto (Firebird), WW/XP for GTO.
Carb 7029270 auto, 7029273 manual.
Exhaust manifolds round port 9797038/9797074 Firebird, 9794035/9797075 GTO.

Hope this helps, and all this info is off the web so I cannot personally vouch for its accuracy.

Thanks Vikki. Do you know if there are any differences in the block? I thought I had read, somewhere, that there were differences between the HO blocks and others. Wondered if this is true for the RA IV's. I may be mistaken, but...

It also seems there were a

That block casting number is unique to the '68RA 4 bolt, '69 RAIV 4 bolt. Besides the four bolt mains that were drilled and tapped and matched with caps, I'm not sure if there were any other differences in the castings. Certainly there were no differences in the external dimensions, as you can bolt all the RAIV parts on a non-RA block, and can tap and align bore for 4 bolt mains on many non-4 bolt blocks. There was also a 4 bolt main 1969 9792968 RAV block.

I don't believe there were any casting differences between the HO/RAIII blocks and the standard and low performance engines. My '69 YT 400 is only a couple of part numbers different from a '69 RAIII. However, there are others on this forum who have a lot more knowledge of these engines, so I defer to their experience.

I forgot to mention that for '69, all 400 except RAIV used crank 9795480, and RAIV used 9795481. Both are listed as Nodular Cast Iron cranks, and the RAIV should be marked Armasteel along with the part number. This chart indicates that all dimensions were identical, but the RAIV calls for .001" more clearance.
http://fiedlerh.home.att.net/PontiacCranks.htm

It's a 4-bolt main engine, all others were 2-bolt. There were some RA III engines that were 4-bolt main but not all. Also the valvetrain in a RA IV was completely different. Longer swirl-polished & tuliped valves & springs, retainers & rocker studs were used. Because the cam was so radical for it's time it required a beefier valvetrain. Also the pushrods were longer & were 11/32" diameter as opposed to the standard 3/8" diameter in all other engines. Almost nothing is interchangeable with any other Pontiac engines. Rocker arms were 1.65 ratio as opposed to the 1.5's in everything else. Rods & crank were not forged, however. It did not need a forged crank, but probably could have used better rods, nonetheless it was a monster engine & the peak of performance in the 400 engine.

Steve

Thanks Steve. Any idea of production numbers? I'm not sure what this guy wants for it. Initially, it sounds like something I should try to own.

WH 126
XN 35
WW 612
XP 165

Buy it, then find the car with the matching VIN and sell it back to the owner.

I have a 67 400 car and it has 48 heads, didn't the 48's also come from a 69 Ram air IV ?

Ram Air III.

Steve