I need some technical questions answered about SBC pistons. What is the compression height and wrist pin diameter of 283 and 327 pistons? Thanks, r
Thanks, that helps alot. It seems that there are no other choices for a lowly 283, than 283 pistons. r
hey kat if you have the right early 283 block you can punch it out for 350 cid piston and have wicked 302 on your hands. the displacement of a 350 but the short stroke of a 283.
Unless you want to change to longer rods, then you might open up options. what if you use the GM 6" (5.94") rods and 307 pistons? that puts you .010 down in the bore, but... it might work?
I don't think you can use 350 pistons even if you bore out the 283 to 4". I thought I could do that but the compressin height and wrist pin placement is all wrong. At least it looks that way when I place the two pistons together, side-by-side. r
You can get some strange combinations with 400 rods. Like 307 pistons, 350 crank, and 400 rods. Comes out to around 327 cid. If the 283 block is 61 or later you can bore to 4in. I built a 350 out of a 283 Chevy II block. The crank dropped right in after the mains were turned to small journal. Strange combinations cost more money though... Jeff
Talk to Glen (AHotRod) on here. He knows this stuff and has the resources to look up any oddball combo you can dream up! He sent me a piston catalog that shows all those specs. I still have it if you need me to research anything in particular for you?
"If the 283 block is 61 or later you can bore to 4in." It's my understanding that the earlier blocks are the ones you can bore out to 4", not the latter ones. I want to use my steel 283 crank and want to get some high compression pistions to bump things up a bunch. I'm wondering if I need to go with a 'spoecial order' piston or if there is something that can be swapped in from another sbc to keep the costs down. That's what drives my question. I just recently picked up a .030 over 327 and might just build it instead. That's why I asked about the 327. I've got a vintage Hilborn intake and a monster roller cam and want to put it all together for some real rpm's and horse power without getting too 'modern' or 'high-tech'. Make sense? r Oh I also PM'd Glenn to see what his thoughts are. Thanks for the lead. r
If you use domed pistons and run a 64cc head you'll lose compression. With the 327 you can build more compression using the same 64cc head.
If you want to use the 283 crank and the 327 4.030 block just order a set of pistons for the 3" stroke and 4.030 bore. You will end up with a 306 cube engine that will rev to the moon!! Boring any 283 3-7/8 bore block out to 4" is risky to say the least and very hard to keep the cylinders straight and cool. Back in the day we used to do this only because a cubic inch rule. Most circle tracks had the rules to keep people from running 327s. I remember back for the longest time of a 307 cube rule. Go figure>>>>.
From what I've read, you shouldn't bore out the very first 283's (1957) too much without sonic checking first, as they're bored-out 265 castings already. I can ask the guy I got my '57 283 engine from for some more detailed spec's, but the short story is that it's stroked with a small journal 327 crank (basically a 307?) and has circle-track racing style forged pistons. It also has 462 camel bump heads and is supposed to be at 10:1 cr.
what about some of those 58cc "claimer" heads or milling the heads you have to bump compression? I'm sure cam lift and valve timing would be super critical.
I'm thinking of either a 302(301) using the 283 block/crank (bored to 4") or just using the 327 and balancing the lower end. This part is for high revs (8-9K nieghborhood). I have a small selection of heads. 1970 vintage 2.02 off a 350 that would need going through, a fresh set of 882 (76cc) or a fresh set of vintage power packs (unsure of the cc's). One engine would be using the Hilborn injection (high compression req'd) and the other engine I would probably build to sell. If I need to get a different set of heads to help with the flow for the injectors, then I will, but I'd like to use what I have, obviously. I'm trying to find out which way would be the best direction with either motor. r
I wouldn't use the 2.02's on anything but the 327. The powerpacks are good for a street car and the 882's are ok for the 327. Even if the 882's are fresh you'll hafta open up the pockets for mucho bigger springs to use them with the roller cam. You can use the 283 crank in the 327 but you'll hafta have custom pistons made for the 302 or if you watch ebay you may find a set. That's where I found my set used.
R, The compression height and pin information is as follows: 1. 283 c.i.d. - Compression height is 1.780-1.795" - Pin-.9275" 2. 327 c.i.d. - Compression height is 1.654-1.675" - Pin-.9275" 3. 350 c.i.d. - Compression height is 1.540-1.560" - Pin-.9275" Other available compression heights are available that were developed for stroker engine combinations: If you were to install a 6.000" long rod in the 283, you would need a piston that has a compression height in the range of 1.480-1.525". You can use a 350 cid piston, and have the top milled off .030-.040". Do you know what compression ratio you are looking to achieve in the 283 combination? Regarding your question as to the availability of 327 hi-compression pistons, what compression ratio are you looking for? Are you wanting a stock-bore piston or are you open to boring the engine +.030 or more?
Found this in the august '02 Hot Rod as part of the article called "25 new ways to build a small-block Chevy." I'm not familiar with the engine, but ran across this article this morning and thought it might help. Sounds a little like what you are working with, for high-revs and all. Let us know what you come up with! A scrappy little 283 race motor hasn't been the hot ticket for, like, 30 years. Why? In addition to being of tiny displacement, the small bores-3.875 versus a 350's 4.000-aren't friendly for the 2.02-inch-or-bigger intake valves guys like to use in performance heads. But now there's a different answer: Vortec heads. These vaunted, low-buck GM Performance Parts offerings (PN 12559060 per head, around $460 a set) have 1.94/1.500 valves that clear the small bores, and they run like stink. We'd throw 'em on a 283 with Speed Pro L2275F domed, forged pistons at 0.060-over (292ci) for 10.9:1 compression with the Vortec 64cc chambers. The solid-dome pistons can be milled for less compression, or you can cut the heads to 58-ccs for nearly 12.0:1. We'd use budget Manley aluminum rods (PN14001-1) just for fun. Combine 'em with a nasty solid or roller cam and an Edelbrock Super Victor intake for Vortec heads (PN 2913), and you could have an 8,000-rpm screamer that makes 475 hp. Also don't forget to sonic-check your 283 block to see if it can be bored 0.125-inch over to a 4.000-inch bore. That makes a 302 and the pistons are available from Speed Pro for either 5.700-inch rods (PN L2210AF) or 6.000-inch rods (L2503F and L2504f).
"Do you know what compression ratio you are looking to achieve in the 283 combination?" If I use the Hilborn on the 283, then I'd like 12.5-13 to 1 compression. "Regarding your question as to the availability of 327 hi-compression pistons, what compression ratio are you looking for? " See above. "Are you wanting a stock-bore piston or are you open to boring the engine +.030 or more?" For the 283, I would need to give it a slight bore, say .030, the 327 is already .030 over but the cylinder walls are like new, so I believe that I could stay with that. NowI'm not real interrested in shelling out mucho bucks on a set of pistons if I don't have to. I know Mahle makes pistons that would fit my bill, but if I can beat thier price by using a different combinations, I will. I already have almost a complete set of 350/4" bore 13 to 1 forged pistons that I would like to use somewhere. That's what got me thinking about all of this. r<!-- / message --><!-- sig -->
If you're going to try for 8,000/9,000 rpm, you're gonna need lightweight pistons and GOOD rods. I don't think you would need a set of custom pistons for any of the combinations you're talking about. You might look at Ross or Manley. Back when Jenkins was running his Vega ProStock car, he tried 6" rods, but ended up using 5.7" in his engines. He said they seemed to work better. I've seen quite a few guys use shorter than stock rods in a 283/302 style engine, 5.7" in 327s and 6" in 350's. Just something to think about. Larry T
Raven, Based on everything I have read, you need to keep the rotating assembly of either engine lite. I would suggest that you sell off the 350 pistons, and apply the money to a set of properly designed forged pistons for the cylinder head that you are going to use. You will also need a strong I-beam or H-beam rod, or even an aluminum rod to withstand the RPM range that your looking to turn. You should not try and cut corners on this engine combination, as it will bite you. A high percentage of the 292-301 small blocks back in the day used aluminum rods very sucessfully, and the rods of today are even better. With the RPM range you have said, you are going to need a pair of heads that flow extremely well to make good HP up there, and #882 are not going to cut it. The #882 head is known for cracking, and has poor flow. Glenn
The only way you will get there is running a 50cc head and milling everything. I was running .400 tall domes in the 265 with a zero decked block with a steel shim head gasket and the most I ver got with 64cc heads was 10:1. FYI.
I built a 301 using a 327 block,heads and rods/ 283 crank. Spun that sucker 7500 with the 375 horse .030/,030 cam, then switched to the second design off road grind and it spun eight five! Never broke, sold it when I went to a big block.
Well, I had to go check (should have before I hit send) and you caught me mixing memories again. Larry T
"I built a 301 using a 327 block,heads and rods/ 283 crank." What pistons? I've got a set of 6" Manley aluminum. I did think about using them in this mess (283 or 327). I know that I need strong light rods and pistons. I'm not into spending $3-4K on a short block assembly. I don't think it's neccessary. If I have to dial down my aspirations of an 8500 rpm motor to fit my planned cash outlay, then so be it. I just think there are more ways to skin a cat. Am I crazy to think so? r
Check these pistons out. http://cgi.ebay.com/ebaymotors/TRW-...7903889QQcmdZViewItem?_trksid=p3756.m20.l1116 They would make the 283 crack!! Just need a 327 crank.
I maybe wrong here but would'nt a 327 block with a 283 crank and 350 pistons on a 6" rod get you pretty close (actually about .040 or so out the top) and you could remove material from the top of the piston to get zero deck height?
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