What year does 350 Buicks start to have the coolant scallops in the center of the heads and block on the lifter galley side?? I have a set on the bench and was wondering.....o No: They have the larger 1.55 exhaust and slightly different casting on the port. casting #1243452
Good topic.Maybe we can settle some things here for research's sake:TU: .What year did they go to the larger valve?What year the cooling ports appear?Same time?What year were the castings revised,even slightly(runners or chambers)?What year did the AIR passages appear?I know this is a loaded question and I believe it to fit right along with the original question,I'm not trying to hijack.I think that a good thread on 350 heads(the ones that we have,not the ones we wish were in production)has been long overdue here.Thanks.
1.55 exhaust supposedly came in 75ish with cat convertors and egrs 68-70 heads came with steel shim head gaskets but chamber sizes should be 58 also from my info ,scallops are mid year 72 that my 70 and 72 engines didnt have holes for air that i remember i think that was a emissions afterthought also. raised port? i can only think of 430 large port or 79up v6 with raised port as far as my i know any 350 heads is comparable in flow/compression to any other year 350(although may not swap due to scallop) so finding 70 hi comp head dont really do much for ya. the differences are suppose to be steel shim head gasket at 020 think and shorter deck compared to laterblocks anyone confirm or deny?
Not to get off topic but Alec asked about the deck height: My 76 and 80 motors are 10.22" and 10.24" for deck height while my 71 is 10.18". Here is a quote from "RocketWagon" who was surprised to find his 75 Buick 350 had a taller deck height than the earlier motors. "Well I did some measuring with my steel rule and vernier calipers and it seems that the deck height on this motor is approx .040" higher than I thought it should be. So instead of being 10.18" deck height it is about 10.22 so I guess that it explains it . I finished putting the top end together on the weekend and everything went together just fine. Next time I will look into a different piston and get the block decked down if I use a later block that has a taller deck height like this one has. Thanks to all that replied for your help. Greg" Oh and sorry about the duplicate post above, it won't let me delete the second one...
I haven't seen any 350 heads with AIR passages in the head for a air pump, only 455 heads. o No: Port/runners look similar on all the head, just slight changes in the casting that where noticable in the short turn and seat area as well as a slightly smaller port. I will get pictures of the differences as it is important for guys to know who are looking to swap around 350 heads between early and late model block. There is no way they would interchange unless you welded up the center coolant ports.
I've only seen one Buick 350 with a smog pump and I'm not sure what year it was but it was painted red and the guy said it was a 71 but I didn't check the #'s.
The scallups were intoduced on the late 72 and sported the 73 castings. 72 Castings No scalups 1238145, has 72 on head 1242145, has 72 on head 1242556 Late 72 casting , no scalups Has 73 on the head. 73 head castings. 1242556 No scalups 1241861,scalups 1243452,scalups Has 74 on head 74 head castihngs 1241861 Has 73 on head 1243452 Has 74 on head 75 and later heads with 1.550 exhaust valves 1243452 Dan
looks like casting info i need to add to the furburger. thanks for bumping it Sean, i missed it the first time around.
1241861,scalups 1243452,scalups Has 74 on head These 2 casting have the air pump holes that go from the intake to the exhaust ports. They mate up to the runners on the intake tubes used on the 73,74 and late 72 smog pump engines. If you use a different intake thes must be tapped and plugeged. Dan
That is lots of casting numbers. Without regard to valve size, is there any opinion on what heads to start with for an all out race motor? For instance, Bill had cracked his ported heads. Next time around will a different casting year be sourced out? Edit: Let me add to that. I have several early 68-72 350's in the shop, but I can pick up a complete 73-81 at the Pull-a-part for $cheap$. Any opinion on what core to start with on a 350 race car turbo build? Crank? Block? Heads? It is a big investment. I want to get started on the right foot/(year motor). It is odd to think they cast the same motor for 13 years without improvements, strength differences, metal properties, etc. Rick, I need a Race Car mentor. Care to help advise me with a build?
but I can pick up a complete 73-81 at the Pull-a-part for $cheap$. if you want to use stock rods, Sean will check in and tell you what year capscrew rods started. 1975 or something like that. i really need to write that down.
I've bought, and am using Carrillo rods and a GT42 turbo. Its the factory 350 Block, Crank, and Heads, that are going to get tested. This is why I wonder about improvements or weaknesses over the 13 year casting run..... If I was picking a 455 block they say go with a '76 because it is stronger than an early block. Now about a 350? For example; Would an '81 350 block have any strength improvements over a '70? Or could the latter have been cast thinner, and lighter?, etc. Unless someone knows some glaring difference, from what I take, one 350 is as good as the other.o No: I would be willing to pick up an '81 and compare it to a '70 (weigh the bare block, main caps, compare crankshafts, etc.) if anyone else is interested.
If I was picking a 455 block they say go with a '76 because it is stronger than an early block. 75 and 76. either year is usually painted blue. the reason for this is that it appears that BBB production for those two years was moved to the Olds engine plant while the Buick engine lines started focusing on the v6 / 350. Would an '81 350 block good luck finding one. there were only a couple of thousand SBB 350's placed in the 1981 model year. likely, all of them were production leftovers from 1980. any strength improvements o No: very little attention has been payed to the SBB. most of us were surprised when Sean showed up and started saying that the 350 deck height kept climbing over the years. who would have expected that? i suppose it would be the easiest production change to make to keep dropping CR while still claiming the same factory rating.
