I am collecting parts for an old school 283 build. I have a 62-66 block, crank, and flat top pistons. I also have a pair of powerpack heads 3795896 also have a good pair of script covers. I have an Edelbrock C-3B manifold and plan on using a holley carb. My goal is decent performance and reliability. Currently I have a .030 350 with wilder cam etc, at about 400hp I know I will not reach that, and that is OK My questions are; how much is to be gained by boring the block, as it is I may just need new bearings, and rings. If I bore how much seat of the pants, or in terms of HP would you gain? Heads: I want the old heads, with no acc holes, and what I have read is that they work ok with the 283 block. Who sells new valves for these? I think they are 1.72 is that correct? Cam: what cam would I need that would match the other componants but have a nice sound? I have a PG trans with a 3000 stall converter in my car now. I plan on stock manifolds, etc and an early external reg alt as well. I am shooting for a 63-64 look for the motor, and want to know with what I have how wild to go, Thanks.
boring a 283 block .030 will give you 287 , .060 will get you 292...and of course .125 will get you 301 (actually 301.7) with everything equal , i really don't think you would notice any seat in the pants difference between any of them. in my opinion , boring for displacement is a waste of time and possibly a waste of a block. with core shift and 40 years of corrosion you are better off boring a little as you can. i have a 283 at the machine shop right now , it was a standard bore with enough ridge to need boring...so it's going to be .030 over .
Some people will tell you to bore the block to 4" and make a 301, but I wouldn't. A lot of blocks will not go out that far and you would have to sonic check it to find out. If you want HP, you would do better with a set of double hump heads. The 461, 462 heads have no bolt holes and flow much better than the powerpack heads and were around in 64'. Find a set that hasn't been monkey'd with, and that is equipped with the 1.94" intake valve. A 2.02" valve will fit in a 283 if you notch the bore, but then the valve is excessively shrouded because its so close to the cylinder wall, and will flow about the same as the 1.94" valve. For a decent rumble, look at the comp cams Thumpr cams. If you really want it to scream and pull some RPM, look at a solid cam and build the valvetrain to match it. I have a set of the 462's sitting in the shop if you end up looking for a set.
Going to be hard to get close to 400hp out of those heads. My 283 has a Comp Cams 270. Sounds great , lost of power in the 2500-4500 range. 097 is a good cam. 30-30 is too sloppy in my opinion.
I may not have exressed myselft clear, I currently have a 400 hp motor, and if I build this 283 I know it won't approach that, I just want to get a good mix of parts to get the most out of it I can.
I am getting ready to fire up my 283 this weekend coming up I will let you know what it sounds like. I have an Engle roller cam part #251 and a set of power pack heads. My crank has been turned .020 both R/M I will try and ask my pops what else is doen to it. But if I can redord it I will post it up .
The specs on my last 283 are. L79 cam Power pack heads with 305 intake valves Edelbrock C4BX .125 pop-up pistons The best I can tell it's 9.5 or 10 to 1 compression with my head combo Roller rockers 550 CFM carb, remember it's less than 300ci not much bigger than 4" stroke flathead.
When I redid my 283 a few years back, I bored it sixty over ... making it a 292. That left cylinder wall meat enough to bore again ... if necessary. I have the block bored with a set of head torque plates ... to ensure a good round bore. I used the Duntov " 097 " camshaft. It sounds GOOD in a 283/292 SBC but I believe I would use a Hydraulic camshaft if I ever do it again. I put everything NEW in the valvetrain ... rockers, poly-loks, springs, valves, keepers, push rods and of course lifters. Some folks do not like adjusting the valves on the solid lifter camshafts. I do not mind it ... but camshaft technology has come a LONG way since the " 097 " came out. I would buy a hydraulic today.
Since your gonna do head work, why not put in the 1.84 intakes like the 305 hi-po heads (Monte Carlo) have.
Your build looks pretty good; my only suggestion is the intake. the C3-B was not a very good breathing manifold. I had one years ago on a 327 and had a noticable low end improvement when I changed to a newer Edelbrock Performer. Id go with an Performer or a Performer RPM intake and the matching cam. Companies like Edelbrock put a lot of $$$ into research designing parts that work well together.
I have the manifold, and was under the imrpession that it would work good, plus it has the oil fill, does he early performer have the oil filler provision? The head info on the valves from a 305 is what I am looking for, since i need new valves anyway. How diificult is it do do head work? Are there any books on the subject?
The edelbrock 2101 has a place where you can drill the hole for the oil filler tube. I threaded the hole i drilled and put in a short vent plug to make the draft hose work better. Also gave better clearance for the altenator. Used a bills high mount bracket system,which mounts to the water pump.
Thanks, soem good things to think aobut. In reagards to the heads, I thought I read that larger valves were not as effective for the 283, and that the powerpack's flow would be a better match. i do not remember where I heard that so... If I were to keep them, I would send them out for the valve work and such, but I was thinking about cleaning the valve areas and the intake runners, I've seen pics done with a hand die grinder. Has anyone doen this type of work? Same with cleaning up the bores as long as they look good, no ridges etc, or should I send it out to have it sonic checked and checked for core shift etc?
The 305s work very well and maintain a good compression ratio. The advantages are harded seats for unleaded gas, larger valves, plus they are readily available and in the end much cheaper than trying to improve the old 283 heads. (which by the way have probably had at least 2-3 valve jobs in their life) The "downer" is they have accessory holes in the ends and do not look like the old 283 heads. But from an affordable-performance aspect, I think they are the way to go. I have used them on 283s numerous times.
Sorry, forgot to add my 2 cents about boring a block. In the old days,serious racers bored blocks as large as possible for more cubic inches. Today they buy an aftermarket block that has or accomodates large cubic inches. The rest of us bore blocks to make the cylinders straight! You cannot effectively seal a piston in a funnel! I cannot imaging finding a 283 block, no matter how good it looks to the eye, that has straight cylinder walls. That being said, most rodders do not drive their hot rod 80-100 thousand miles. So you might be able to "get by" with using old pistons in a worn cylinder bore and not "blow the blues", but you will certainly have diminished power. I have done it a few times but dont like doing it. Normally, not only are the cylinders worn, but the piston skirts are worn and the top compression groove in the pistons are also worn. All those problems are gone with a fresh bore and a new set of oversize pistons. Thats my story and I'm sticking to it!
This may be viewed as blasphemy, but if you want good heads with no accessory holes, why not GET good heads, and fill the holes with epoxy or body filler. Stipple the surface with a sponge so it looks cast, add a thick coat of paint, and you're the only one who'd know. Ralph
I was concerned about this, the only thing is I know that block has been apart before because someone marked the rod caps, so it may have been bored, but I would have to measure it to see, or maybe was taken apart for rings and bearings. sounds like it would need to be stripped down and checked.
Sounds like a cool plan. FWIW I thought Edelbrock just released a version of the performer (or RPM?) with the fill hole. Maybe I'm mis remembering, but I saw something about that in print recently, and I don't recall it being a re-release. Funny, I was gonna reccomend a 'Duntov'.
The motor in my car now is a later 350 dressed to look like an early motor, with this one I wanted to, over time collect the parts to do it reallty right. i could go this route, and money may dictate that I do, but right now I'm hung up on this period piece...
I read that you mentioned that you're going to run exhaust manifolds. If so, you might want to consider these affordable rams horn reproductions (the larger outlet 2.5" corvette versions) http://www.midwayautosupply.com/m-114-dorman-exhaust-manifold-kits.aspx or http://www.performanceexhaustplus.com/0/19/0/126/shop_by_category.html
Concerning the bigger valves in the heads: I'm going thru this right now with a set of double-hump heads. 2.02/1.60 valves WILL fit in the bores, but just barely. (there's some debate on whether or not you'll have to nick the bore for clearance) Lamar Walden's shop in Doraville, Georgia is doing the heads, and left the 1.94/1.50 valves, saying the valves bigger valves will be shrouded being that close to the cylinder walls. A) Lamar and his shop have been Chevy experts since the '60s, including being a factory-backed racer in Gas and Pro Stock. B) we cut the valve seats on a Serdi machine, and will have to buy all new valves, so there was no cost savings or work savings in staying with the smaller valves. It would have cost the same amount of money to put in bigger valves, and he recommended against it saying it could actually lose power. The Edelbrock C-series of intakes: I've got a C4B on the 350 in my Suburban, and it does pretty well. I also have a C3B and a C3BX, and another C4B: At one time, the runner layout was different on the C4Bs: one version of the C4B has two very long runners and two very short runners per side, while another version of the C4B has all the runners with more even lengths. Do a search, because someone who had all of them before I got mine posted a picture to show the difference. I have to believe that affected power. The version with the more even runners looks a lot like a Performer, but the Performer is taller. There are probably other benefits to the Performer, but I think by being taller, it has longer runners or more sweeping turns inside the runner. I plan to put all of them on a dyno and flow bench to see how they do. The C3B has a notch in the plenum divided to clear the Holley 3bbl carb's long throttle blade. I've quickly looked, but can't see any visual difference between a C3B and a C3BX. While we're on the topic, does anyone have a source for 301 pistons? -Brad
Thanks for the info about the heads, and manifold. I have a C3B in my motor now, but the plenum divider was filed down so there is no nick but one smooth lower divider. The other I have for the 283 has the nick intact. I know the C3B was out in the 60's, and I have a Hot Rod mag from 1970 that introduces the C3BX but without an explanation of what or how it is different.
Is there a disadvantage to running the canister filter? I'm also building a 283, and would like to keep it.
I do not know if there is a advantage or not, I believe that it was a jab at me for trying to build a "period correct" motor with a new oil filter. I just happen to have the spin on adaptor is all...
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