Ok I pulled this engine from a 68 chevy 3/4 ton its a truck engine with two eyebrows on dished forged pistons. It had steel shim head gaskets. A Q jet intake with a oil fill tube. The old engine is locked up. and had set untouched for several years. Today I decided to pull the intake and use it on something else with a adapter for a square bore carter carb.. What got me is the back of the block is cast for a oil breather and canister but not machined out. The pistons since they have only two eyebrows must be hung with the notch to the rear on one bank . The heads aint anything special just truck heads. I think a spun bearing is the reason the engine is locked up. It had a huge holley double pumper spread bore carb on it with stock single exhaust. It still has a steel canister oil filter. Im not asking a question. I just thought you all might be interested in seeing something not often seen. I think with large chamber heads a engine with those forged pistons would make a good blower or turbo charged engine? I think its a large journal crank because its tapped for a bolt. The block is tapped for the front pedestal mounts also.
The 1968 engine went to the closed pvc system which is why there isn't the breather under the intake manifold. It does have the large journal crank.
Ive got another one of those truck 327's its a 66 small journal. It has the same dished forged pistons. it had power pack heads and the small Rochester 2 bbl carb. The truck it came from was a 1966 3/4 ton with a turbo 400 auto trans and a No Spin Rear with 456 gears. I had done a ring job on it and installed it in a 1/2 ton with a powerglide and tall rear gears. Fixed it for my older son. It lasted several years. Then he installed a 4 bbl carb. and got a water leak at the thermostat housing and overheated it and it went to smoking and burning oil. I gave him a 250 six to replace it.
I will likely pull the pan tomorrow. I can tell by the parting line if its a steel or cast crank. and journal size by the rod nut size. I don't plan of doing anything except slathering it with a thick coat of chassis grease and storing it in a school bus. The heads I will sell to a core buyer.
Regarding the piston notches; I'd always been taught the notches were meant for CAST pistons, and the notches always faced the FRONT of the engine. 4 notched one way, 4 the other in the box, but once installed in the engine, they all face the same way, to the front. I've heard the production line guys did some odd things at quitting time, maybe your 327 is one of them. Thrown together to finish what they were doing, with what they had at the time.. Someone mess up at build time? All this talk about notches has got me hungry; I think I'll go get some nachos. I am Butch/56sedandelivery.
Nope The pistons are installed correctly. since there are only two eyebrows and they only made one piston. you simply install those type pistons with the notch facing the back of the block and the eyebrows up on only the passenger side. Ive seen a half dozen of these Truck 327 engines with the same piston setup. And they are forged pistons. Made to take more heat than a passenger car piston.You hang the rods so the Rod to Rod mating surfaces are correct with the notch facing rearward only on the passenger side. That's one reason I started the thread its a oddball not often seen version of 327. I have another 66 truck 327 with the same pistons. and once owned a 67 GMC with the same pistons in a 327.
Cast iron is easily drilled. If I ever use that block I will drill the passages to install a PCV at the rear of the engine. I don't like valve covers with holes in them.
I don't mean any disrespect, and even though I'm not from Missouri (I'm from Alaska), but show me; some literature, articles, dealer memos, something. And while you're at it, look up #602 heads also. I am Butch/56sedandelivery.
Butch, it would stand to reason if you had 8 pistons for a SBC, with 2 valve reliefs, all built the same way. 4 notches would be to the front and four would be to the back of the engine.
The pistons should have a G.M. casting number of 3796494 inside the skirt. They are 62-8 Chev. H.D. Truck, low compression, recessed head .085 x 3.125, 8.0:1 compression. They have a steel insert cast into the top ring groove (armored groove) These pistons are a cast piston. The good news is that being a 68 327 truck, it most likely has a rare forged steel large journal 3.25" stroke crankshaft.
I had one of those oddball 68 blocks way back when. But mine was a 350 4 bolt with the unmachined PCV . Didn't all 68 and newer blocks have spin on oil filters?
According to the Nasty Z28 list That is indeed a 68 block. Same casting number that was used with a 302 or 327. A few pieces and a guy could use it for a correct casting number 68 Z28 302. 1968 3914678 302 290 290 2/4 Camaro, Z-28 1968 3914678 327 210 350 2 car & truck
I used the same block to build a 350 for my model a. I drilled and tapped the boss for a pcv valve. It's neat to hear a possible application since I never researched it. It is the only one I personally had my hands on.
IF the pistons are is as the Wolf has said, I'd like to see the info that he bases it on. Personally, just like any cast piston set for a SBC, the notch would face the front; the only real different here being that there are only 2 valve reliefs, and not 4 reliefs. The would be no problem casting 2 valve reliefs, with the notch facing the correct direction of all of them facing the front. Why would GM/Chevrolet do this with only one year truck and one sized engine? That makes no sense to me and surely not to the bean counters at GM/Chevrolet. I believe they are a cast piston for basically the same reason; I've never seen any such forged piston. But then again, all the pistons I've seen that were dished and had valve reliefs had 4 of them. The steel support at the top ring land is something I have not heard of, something that's plausible to steady the ring in the land to help the engine last longer. All cast pistons have a notch in them, that's to face the front. I always thought that was because the piston pin is't "centered" in the piston, but offset, so you'd want the piston facing the correct direction, although racers used to flip them around to improve on their geometry; race engines are't long use engines however. I've seen similar, dished pistons for 327's, but they had 4 valve reliefs AND the forward facing notch. The reliefs in Wolf's pistons look cast in. I have 2 sets of 350 pistons I bought off of E-Bay; Sealed Power, #2393P .030, they are Made in U.S.A., have 377-99 on the inside, with an upside down triangle and a "T" inside of that. The boxes are all marked FOR EXPORT ONLY. They are a Machined flat top, with casted in 2 valve relief, pistons. Very high quality work. They seem really odd to me also; and why For Export Only? I would like to see both banks with the notches facing the front on one side, to the rear on the other, and of one of the other 327 engines just to put a nail in my coffin. Like I said, no disrespect here, but it goes against what I've been taught/learned; he even says "Oddball 327 Chevy" in the thread title, so he's expecting some "what's???". I'm not saying Wolf's not right about the notches facing to the front on one bank, and to the rear on the other; I want to know "why" that is, I fully understand about 2 valve relief and notches. And hey, I've got a #1178 crank if it's a 302 you want to make, and I have a good set of rods I'd toss in. I am Butch/56sedandelivery.
I stand corrected. I always thought they where forged. I knew they where a HD piston. That's why I think they would be a good blower engine piston.
However that's the fact I was wrong about them being forged. but its not just one year of 327 truck engines that have those rearward notch pistons on the passenger side bank. I also have a 66 engine with the same pistons and have personally seen a half dozen. My 66 engine isn't torn down and is stored in a bread van along with a lot of other engines with lumber stacked on top of them. Be a chore to dig it out. Not to be mean however you are free to think what you wish. It don't matter to me. When Im mistaken or just outright incorrect I will admit it.
Yep ive seen those long canister oil filters and large capacity oil pans. My C65 with a 366 big block has a 8 quart oil pan.
I don't think the '68 block has 4-bolt mains.... That was in 1969 and newer... A steel crank maybe... I'd love to see that one....
I bought a 68 Nova Custom off a used car lot back in 73 . It had a 327-325 hp with a fully synchro 3 speed on the floor. It had a large journal 327 , 2.02 heads with a Qjet. what a sleeper .
Ok I just pulled the oil pan. its a two bolt main. and a steel crankshaft. And No metal in the pan or discolored rodcaps ect. Now I wonder why it was and & is still locked up? I suppose a cyl soak is on the agenda? We pulled the engine and installed a 350 in the truck it came from and the trans and everything was still good.
I have a full set of these still mounted on the original connectimg rods. I am in Camas, fairly close to you so if you are ever in the area and would like to check them out for yourself, just let me know and we can get together. P.M. me if you want contact info, G.....
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