The Jalopy Journal
Discussion in 'The Hokey Ass Message Board' started by Holmes Cycles, Jun 7, 2019.
Thanks for the info. When I pull the heads off, I'll take a look!
If that link was supposed to be for cylinder head info, it wasn't....that is 18 pages of Chevy II's
You will also find the 461X heads with the "461X" cast down inside the large open waterport hole in the deck, rather than the bottom of the runners. I've even seen photos of "461" across the bottom of the runner but "461X" on the surface down in the round water port .
There is also a difference between the 461x cast across the bottom of the intake ports, and 461x cast along the same direction as the port runs....the lengthwise numbered heads are supposed to be better in some way than the cross-wise numbered versions, but I don't remember what that difference was. It was in a thread over at SpeedTalk forum. Seems like it something to do with thickness of the spring pad or how far that could be machined either diameter or downward, but don't quote me on that.
I have been wondering the same with a future 283 build
I have power pack heads and a rebuilt set of 462s small valve.
Not doing 305 heads
Good info...in '63, my bud Ramsay bought an over-the-counter 327 short block. He had local SBC guru Chris Seavers port a pair of 265 heads, (!) aluminum intake WCFB carb.
Woke his '57 Chev up...
I built a 283 for my pal Dick, Gen. Kinetics cam, Power Pak heads, matched ports, new AFB carb, alum. intake. Dick's '56 Chev with that 283 nosed Ramsay out 3 outa 3.
Gotta love those 283s!
I'm building a 283 'budget' engine as we speak...cast iron rings, 8/14 cam, solid lifters, Powr Pak heads, Mallory ign., marine conversion (crab cap) It'll be a "for now" engine for my tub and roadster, tub will get my flathead later.
283 has an aluminum flywheel, Merc pressure plate/disc, and adapter to '39 Ford...
Try it again.
I guess what I'd be asking here is, what pistons are you going to be using to build some compression into a 283? It's really hard to build any kind of CR with these short stroke/small bore engines, especially once you throw a pair of 64 cc chamber, or larger, cc heads on the short block. In fact, most 283's were low CR engines; even the dual quad/fuel injection engines had barely over 9:1 CR . Most 283, Power Pack heads had around 60 cc chambers, but some of the truck "Power Packs" (why even call them that?) had 70 cc chambers (to use really cheap, fleet type, gas), a real CR killer. The smallest chamber 1956 Power Pack head had 56.6 cc chambers, but they also had a very restrictive "trough", between the valves. If you don't have some rather large, domed pistons, along with steel shim head gaskets, serious block decking/head milling, building a 283 is really, all for not; the industry no longer makes readily available, decently priced, performance parts for an engine that has't been made in over 50 years. Now, I do have my fair share of 265 AND 283 engines (3 of them), but I've also been collecting the RIGHT parts for 30 years or so. I think the "average" guy, who wants to build a 283, should start with a post 1962 block, use a small journal 327 crank for the added stroke (='s a slightly higher CR), deck the block, mill the heads, use steel shim head gaskets, and use no more than 2 valve relief, flat top, pistons; preferably a small domed piston, but that also means taking the bore to the 327's 4". It's a LOT easier to find performance 327 pistons than it is to find 283 pistons, without paying a premium for race type pistons, if you can even find them. Then, just point out the 283 casting number and Power Pack heads, to sell the idea of it being a "283". My personal advice, is to stay away from the 64 cc and larger chamber heads, and don't get carried away on valve sizes that you just don't need on a street car. ALL my 265 and 283 Power Pack heads have 1.84" intake valves (see, the 305's were good for something), NO hardened seats for the amount of time they're run, Z-28 style spring kits, and just a little bowl/port work. I remember, when I was in high school (66-69), 283's were the engine everyone wanted, but few that could actually afford to build; now it's finding the right parts, without breaking the build, bank account. I am Butch/56sedandelivery.
Isn't 9:1 CR approaching the limit you can run on available gas these days? Less than 10:1 anyway? Maybe add some water injection for higher ratios? I don't know, just asking.
The OP stated he wanted "300 HP from his 283"; that will take some work, including some higher CR pistons or possibly a supercharger/turbocharger (starts to make for an expensive 283). "Most" 283's did't have much more than 8.5:1 from the factory, some had even less, as in the case of fleet trucks. BUT, depending on the year of the engine, mid 50's to mid/late 60's, 8.0:1 to 10.25:1 was sort of the spread in CR of the 265's and 283's. I think some of those numbers are off however, especially when the same pistons and heads were used but the CR varied (???). Must have something to do with the "new math". The small bore (305 + .030 overbore/334 CID), flat top pistons with 4 valve reliefs, and a cut down 400 crank, in my daily driver heavy truck, makes for some interesting sounds coming from the engine, unless it's run really retarded. And that kills the power to an extent I wish it did't. The CR of my 1 265 and 1 283 engine is't much more than 9:1, maybe 9.5:1 at best. The remaining 283 has .125 domed pistons and an 097 cam, and it had been a street motor long before I came into it. Of course car weight, gear ratio, tire sizes, and many other things can affect how well an engine "runs". That's why I suggested the later 283 block with a 327 rotating assembly; better to just start with bigger from the beginning, unless you're building for a purpose, like I am. I am Butch/56sedandelivery.
I've always been under the impression that the coveted 461"x" heads had the "x" cast after the casting number under the valve cover, on the top side of the head. They are "supposed" to be in the 170cc range, which I think, is WAAAAY too much for a 283. JMO. Does anyone else have confirmation of the "x" location? Or have these so called "guru's" been blowing smoke up my ass all these year's??? Some how I wouldn't be surprised if it was a "smoke-out!"
062s are good there 300hp 1969 1970s Camaro heads with accesory bolt holes
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I think that your c/r will be lower with the stock 1.94 heads .
In the 60's if you built a 283 based engine with camel hump heads you were running raided dome pistons of some sort and higher compression ratio. At least for the local fast 283 guys around here that was the norn usually with over the counter Chevrolet parts. Pretty good thread here on using factory parts https://www.jalopyjournal.com/forum/threads/283-ultimate-engine-using-oem-parts.871936/
I'm still thinking that you have to relieve the top of the cylinder wall to be able to run 2.02 valves in a 283 unless it is bored out far enough.
In the late 80's we stuck together a 307 out of left over parts and pieces for my son's 70 C10. 307 block that had come out of a 72 Chevelle I had picked up, power pack heads with unknown casting numbers but they matched. 300 hp 327 cast iron intake and a Holley 650 carb with a swap meet Z28 hydraulic cam that probably came from a mid 80's car. Got that at the Portland swap meet with numbered lifters for 25.00 in 1987 I think. With a granny 4 speed and 3.7 gears that thing was a terror in stop light to stop light goes from the feedback I got from others. It also pulled 16 mpg on a road trip to Texas. I don't think you have to have fancy you just have to have a combination that works.
Still 300 hp from a 283 is going to take some serious work and some compression to accomplish with era correct appearing parts.
I’m afraid that 300 horsepower from a 283 is asking a lot. What about a 350 short block with “traditional” looking heads. It would be far easier to get 300 out of a 350 and the torque will make for a much more fun street engine. Besides, you don’t have to tell anyone it’s a 350.
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My favorite setup, on my 265 B/EXGD engine in the early 60's was flat top pistons and what we called '57 FI heads. These heads had larger ports than early power-pac heads but had combustion chamber bumps on either side of the spark plug to raise the compression. If memory serves me the symbol on the end of the heads was like the top half of the capital letter "H".
^^^^Twin tower heads is what we called them^^^^; some 56 and 57 heads had similar markings, and there were some truck heads that had them also. I am Butch/56sedandelivery.
How bout a set of "3795896"
Will those be any good?
iwanaflattie….those should be workable, chamber looks like a smaller version of the early Fuelie "461" head type..
The "520" castings have a little bit better chamber shape that is a smaller version of the improved Fuelie chamber used in 462, 186, 492 and other later closed chamber 64cc castings
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