Hey all, I have a supposed 67 GS 340. Heres the problem, The block is numbered (KP239) on cyl. deck which makes it a '64 300 right? It also has alum. cyl. heads and intake-4bbl. The firewall number is (ST-67-43407)---(BF02332)body TR-110 P2-paint B80 B90 CO8 Door jamb: 43307 7Z117934 What is the difference in 300/340 just the crank? Thank You in advance for your help, Murph... :beer
I'm only 90% sure of what I'm about to say... but I'll say it anyways and someone can correct me if I'm wrong.... The 340 is a "one year only" engine from 1967. None of it's parts fit anything else, excpet maybe a bracket or two. The block, heads, intake, exhaust, etc... everything is different in the 340. As far as I know, NO aluminum heads were ever made for the 340 either. I'd be willing to bet quite a bit of cash that you have an older 300. Definately not original to a 67 Buick. I have heard/seen people putting aluminum Rover heads on the Buick 300 with adaptor plates, so you might even have something like that. But I'd guess you have an older 300 that came factory with aluminum heads. 64 is probably a good guess. o No: Do you have any pictures of your car? We'd love to see them! :TU: :beer
340 was 1966 and 67, no alum heads.....and nothing interchanges with anything else in the Buick line except brackets and such.
340 65-67 300 iron heads, exhaust manifolds and valve covers interchange , I got a set on my 340 right now, runs fine.
Interchange Guys, Actually alot of things interchange here the list: exhaust manifolds valve covers - flat style timing cover Oil pump cover - filter housing Distributor and drive gears cam and lifters timing chain/gears pulleys water pump rocker and rocker shafts Alt., P/S, A/C brackets most every attaching bolt on the engine is the same as a 300 Most 340's from the factory were painted Red 300's usally had green valve covers
Well if you have to have an incorrect small block, you got the coolest one for your CA GS. I have one with the smog pumped 340. Not sure how it runs yet. The aluminum head/intake 300 is a good one. How does it run? I do not think the heads and intake will bolt up to the 340. :ball: If they did, I would do it.
Hi, From what I have read, the 300 and 340 are much the same except for the stroke. I think the crank is the same as a 350? Mark
I thought the 340 had a unique cam design (where each cam bearing lobe gets a little smaller diameter from front to back through the engine)
Hum...I've been told over and over again in this forum that no other intake will work on a 340 and the only thing from a 350 that will work on a 340 are some mounting brackets, motor mounts but no valve covers or such, I would love to really know what the deal is cause i'm fixing to change from a 340 to a 350 because I can get stuff for the 350.
Thanks for all the help guys. I have found through reasearch on here and elsewhere, That the 67 GS California was based on the post model Special or Skylark. There also was a GS ornimentation only pkg. which i think this car is, if so there were only 544 made! It has GS emblems on the sail panels, quarter panels, front grille, and rear trunk trim. The motor is a 300 i checked the stroke. The bore is the same on 300-340 3.750 from what i read the 340 is derived from the 300.
Ted, The 300 had 174.000mi on it before teardown, it ran very strong, real tire smoker! I only tore it down to refresh it.
I'd like to know too James. At one point about 6-8 months ago, I had a two 300's, a 340, a 350, and two 455's here at my place and I could have compared them all side by side. The 340 is what was in my 67 ragtop when I bought it. I was going to throw a cam in it, until I found that I couldn't get any parts for it. Especially not a performance cam. You CAN get a cam for the 300, 350 and 455's though. Thats what leads me to believe they are totally different. I know the 340 intake is a couple inches wider than the 300 intake. It was noticeably wider. o No: I went for the 455 in my ragtop and sold everything else. :Brow:
The only intake that will work on a 340 is a 340. Since the 340 has a 3.85 stroke (300's had a 3.4) the block is wider. The 300 manifold would be too narrow to fit between the heads. Likewise, a 340 manifold is too wide to fit on a 300 (I found that out the hard way). All cast iron head 300 and 340 should be the same and interchange. Am pretty sure the valve sizes are the same. The aluminum heads are unique and valves are a bit smaller. They may bolt up, but don't know if you will have problems with water jackets and core holes. Then again, intake will be a problem. 350 valves covers use 6 bolts. 300/340 uses 4. So, they don't swap. Timing covers will swap, but there are extra bolt holes on the 350 that may or may not be on the 340. These are by the larger water passages on the side of the pump. The 67 340 may use those bolts, but early 300's did not. Water pumps are the same and distributors will swap as well. Oil pans and pickups will work between a 340 and 350. The cam on a 300/340 does not have different lobe sizes. What it does have is progessively smaller journals and cam bearings. I guess the theory was that it was easier to put the cam in with a small journal on the end of the cam and larger ones as you moved to the front. Less chance of nicking a cam bearing. There may be other items that escape my old memory at this moment. Hope this clears some things up, Mark
You may have what I have. A pretty rare W-1 option special / GS. Looks like a post model GS with all the trim except hoodscoops, has the "hoodspear" instead, and came stock with the 300 mill or sometimes even a V6:shock: This is the GS ornamentation package you are referring to. I too bought ione thinking it was a GS340, until I ran the numbers and did some research. I'm curious though...where did you get that "544 made" production number ?
67 GS CA I have lots of issues and need to clear my mind (cheap tequila should do the trick) but anyway..... The car is the same as other gs californias I have read about with the VIN being 43307 = Special Post coupe V-6, then the firewall has the 43407 designation. (I have one too) Its a special body and interior from the cowl back(first thing I wanted to check was the frame and it is Not Boxed), and has a GS hood and front fenders. 340 engine with all the CA smog pump stuff. Murph's car has a 64 engine in it, with the cool AL heads and intake-cool swap. I think the nailhead cam is the same way with the cam bearings progresively smaller from front to back, not sure but may be true for a lot of engines. 340 appeared in '66 in the Lesabre and skylarks, again in '67 in the GS 340, GS CA, Skylark and LeSabre. Poston sells performance cams for it, I have seen PAW has parts. Pistons are the same bore as the 300. Thats every thing I think I know, now for the tequila...... :TU:
Yes this one has the hood scoops though. No boxed frame, no posi. The 544 made came off of here. Search for-67 GS California, It was in one of those threads. Im going to go ahead and rebuild the old 300. So far i have a Poston cam #sb114, springs #pe104. adj pushrods #pe130. and headers (which Poston still makes).Clevite rockers and shafts, lifters, all bearings and H.V. oil pump and front cover. I have a set of Badger pistons .040 10.25:1. Perfect circle moly rings and oil seals. I have already ported the alum. heads, and intake. All i need is to get the machine work done on the short block.
Cool amn. I have the 64 aluminum heads and intake, that will both go on my 300 next summer, along with most of the Hi-Po stuff you mentioned. Very cool. I think your car is a California GS, but someone swapped out for the 64 300 somewhere along the lines. But what the hell do I know I'm only a rookie. I am pretty sure a W-1 like mine would only have the hood spear though. I don't believe any of them came with scoops, but stranger things have been known to have rolled out of flint in the 60's, that's for sure. How long ago did you get your headers?
