[unruhjonny]

Originally Posted by tom s

URJ,from what I have learned that the 303s and 366 blocks even with RA IV heads got the larger dist.You can tell what the block was or intended for by the placement of the valve reliefs.My 366 was for sure RA IV as it had IV heads on it when the previous owner received it.I started to build it as a IV but decided against it and do it as a V.Will know more about the 303 block when its actually in my hands.As said,never say never or always.Tom

huh - cool.

I had previously read (or recall reading) that they were built as RAV engines, and that lackluster performance had teams swap to RAIV top ends on those engines.

Thanks for the insight!

[tom s]

The 303 SCCA engines were built as short deck,the factory made 25 complete engines with exhaust manifolds.SCCA outlawed the short decks and the factory went to std decks and they were not up to the task with either head.I really think all the 366 NASCAR engines that got on the track were IV top ends.Back to the OP.Tom

[74SDformula]

In the early 90's I bought an engine from a guy named Tom Harper who had a body shop in Atlanta, GA. The heads were some 614 castings that had a DS number stamped on the center exhaust ports. Later upon taking the heads apart we found they even had titanium intake valves in them. Upon looking at the valves very closely it was noticed that both the intakes and exhaust had DS numbers etched into them near the lock grooves. I still have the heads and the valves. Have no idea of the prior use of these though.

[unruhjonny]

WOW!
That's super cool!!!

[dataway]

Ti Valves mean Stellite seats in most cases doesn't it? I didn't think Ti would hold up in iron seats ... specially on the exhaust.

[sdbob]

I had a set of 366 RA IV 180 degree headers from the Grand Am. They were very nicely done.Traded to Randy Williams.

[74SDformula]

Originally Posted by dataway

Ti Valves mean Stellite seats in most cases doesn't it? I didn't think Ti would hold up in iron seats ... specially on the exhaust.

These heads only had titanium valves on the intake side. The exhaust were stainless steel. Forgot to add that they also had titanium retainers.

[ho428]

My V block has the lifter valley webbing, 4 bolt mains, large distributor hole, no stamped codes anywhere but it did have a very lightly stamped XP placed randomly on the deck. The block was virgin when I got it. The casting number was garbled to the point of almost unreadable, heard somewhere years ago that they did that on purpose? Got a picture of it somewhere but the first few numbers matched the RA V casting code, the rest matched nothing. It's a standard deck with 4.125 bore, 3" main. Machine shop I had bore it for it's second build said it was the hardest Iron block we'd ever worked on. He surmised a high nickle content.

Bought it from Ronnie Hopkins racing back in the 70's, he got them direct from Pontiac and had 5 blocks for sale since he'd switched brands, but as an 18 year old kid then I couldn't afford them all at a whopping $250 apiece so I just got the one. Would love to V the top end but it's just too expensive.

Tom, Ronnie told me back then he tried the V head but switched back to the IV heads after failures. If I recall he raced some Can Am but mainly NASCAR back then.

[unruhjonny]

Originally Posted by ho428

(the) Machine shop I had bore it for it's second build said it was the hardest Iron block we'd ever worked on. He surmised a high nickle content....

cool!

[johnta1]

ho428, what is the date code on the block?


That's cool how you got the block.
Never knew anyone having RA V stuff back then.

[Mike Davis]

Originally Posted by 74SDformula

In the early 90's I bought an engine from a guy named Tom Harper who had a body shop in Atlanta, GA. The heads were some 614 castings that had a DS number stamped on the center exhaust ports. Later upon taking the heads apart we found they even had titanium intake valves in them. Upon looking at the valves very closely it was noticed that both the intakes and exhaust had DS numbers etched into them near the lock grooves. I still have the heads and the valves. Have no idea of the prior use of these though.

Is this the same Harper Body Shop that is in Dawsonville now?

I have a 428 4 Bolt Block that has a DS stamped on it, confusing it had XF on it as well. The block was new/never ran when I got it in 1989. The block was wrapped in a GM Engine Bag and bolted to a small wood pallet. The guy I got it from was in Atlanta and worked for Boomershine Pontiac in the late 60's early 70's. The main caps look like they were polished they were very shiny. Block had all lifter oil feeds tapped for restrictors.


He had a ton of Ram Air IV stuff, a set of RAV heads and 2 complete 455 SD's.
He wanted $4000 for all of it but being a broke college student I could only swing $400 for the 428 Block and a 990 421 crank.

[muscle_collector]

never know about the V stuff. a couple of my other ra5 blocks had the full casting numbers on them. and they had the ra5 engine code stamped on them also. I also have ra 5 heads that have the DS #'s who knows about this stuff.

[poncho-mike]

I had a 1970 400 block with 4-bolt mains that had the distributor hole drilled out to Ram V size. I got it back in the mid-80s from a guy in SC that raced Ram IV, Ram V, and 455HO cars in the late 60s into the mid-70s. It's been so long I forgot his name and any history, but I do remember him telling me he ran it as a Ram V. The heads had already been sold. I seem to remember this guy was either sponsored by Pontiac or a Pontiac dealer because he had a lot of NOS performance stuff that had never been used.

The cast date on the block was October or November 1969. I had a 1970 Ram IV Judge missing the original motor, and the cast dates aligned perfectly.

As best I remember, that block had no numbers stamped in it at all. It had the normal Pontiac style lifter galley, no provisions for dry sump, and pretty much looked like a normal Pontiac 400 4-bolt except the distributor hole had been enlarged. RAMIVJUMB bought the car and the block, so maybe he can weigh in regarding anything abnormal about the block.

[muscle_collector]

that's kinda like this one seems to be.

I put it and the heads and intake up for sale in the gto parts for sale section.