Improving a 283

[Backpayne]

I recently purchased a '64 c10 with a 283. I'd like to keep the engine but would like to do some improvements. I do not want to spend a lot of money, however. I will be taking the heads off later today to see how the cylinders look. No point on spending money if it needs block work.

What would you recommend?

Here are some parts I'm thinking of:

305 HO heads (used)
Camshaft
Intake


Would these be the best parts to start with?

[RustyPile]

Bore it to 4 inches, making it 301.. Then big valve heads can be used.

[Willshook]

I wouldn't bother pulling the heads - just do a compression test. If the compression is mostly OK, drive it and get through a few oil changes to make sure it's healthy before doing any upgrades.

305 heads will give you higher CR by a point or so...but that's not going to make a huge difference at these power levels and they're otherwise crappy heads. Avoid.

Small-tube headers, low-rise intake with a small (450 CFM) 4-barrel (or Holley 2 barrel) and a mild cam upgrade would be as far as I'd go on that platform. Might as well do a stock HEI "while you're in there". With some luck, that puts you around 220+ HP at the flywheel, but with good throttle response and power. That's as far as you go without getting into the internals.

[Dead Parrot]

2nd the HEI idea.
Are those rams horn manifolds? If so, I doubt any gain from headers would be worth the cost and hassle.
Get some valve covers that accommodate a PCV system. PCV does a lot to keep the oil clean. Plus most modern carbs are calibrated with the assumption of a PCV system. If you swap manifolds, you will likely need an oil fill port on one of the valve covers anyway.
A new cam implies new lifters and cam break in oil.
For a manifold, some variation of an Eddy Performer/Performer RPM + a small modern 2 or 4 barrel carb.

Suggest HEI + manifold/carb + PCV and run it for a while. If it runs good and doesn't leave a smoke trail worthy of a WWII destroyer, then consider doing more.

[Tom]

If you want 305 heads then get 305 vortec heads.

Originally Posted by Dead Parrot

2nd the HEI idea.
Are those rams horn manifolds? If so, I doubt any gain from headers would be worth the cost and hassle.

Depends. There are 2" ram horns and 2.5". 2" ram horns dont flow any better then later log manifold.

[AcampoDave]

I run a 283 bored 60 over which makes it a 292. I use an HEI, Edelbrock Performer EPS manifold, RV cam with a 500 cfm performer carb jetted 2 stages leaner on primaries and secondaries. I run 305 heads (416's) which are ported and polished with roller rockers. These heads keep the compresion a tad higher than stock but provide slightly larger valves and hardened seats for unleaded. I also stuck with ram horns combined with dual pipes. Keeping valve size and exhaust pipe diameter conservative keeps air velocity high for smooth spirited throttle response. I can drive all day long on a tank of gas and the motor sounds delightful when I bang thru the gears. The small motor is a bit lopey with the rv cam and the sound turns heads in town. It is powerful for its size, but better described as spirited and fun to beat on. It winds up fast but at a guestimated 250 hp it's not a serious burn out maker with 308 rear gears. It will burn out with some clutch, but that's not really what it's built for. The RV cam is a 281int/296 ex with an SAE duration of 278/288. I stuck with the rv profile because a small motor will "feel" it more than a bigger one. The 283 has a short stroke which lends to its durability and longevity. The smaller crank circle exerts less side to side thrust on cylinder walls. Think about a ratchet. A tight bolt requires a long ratchet (the long stroke motor) but, once you break it loose a shorter ratchet (the 283) can do the work fast and easy because the end of the handle travels in a smaller circle. You can spin it very quickly. Each rpm on a short stroke motor is basically less rotational distance traveled. That's the upside, the downside is sometimes you just need a big freakin' ratchet.

That's what did to one. I spent more than I would of for a stock 350 and got less power for it, but I don't care. It's just fun to hammer a 283 for all its got and I do it a lot.

[theastronaut]

416 and 601 heads are excellent for a 283, and with a bit of port/chamber work will make 300 hp easily with the right cam and intake/carb. I believe 416 heads have 58cc chambers and 601 have 53cc. I have a pair of 601s that I planned on using on a 283. The smaller runners make for great low rpm response but flow well enough to make good power up top once ported. There are guys running 11s and 12s with ported 305 heads, they're not "crappy".


Check out the posts by Jeff Swisher in this thread-

https://www.chevelles.com/threads/th...thread.318551/

[Willshook]

Chasing a point of compression at this build level is futile, but some racers prefer small chambers as it opens up other build options - and some classes are restricted on head options so they spend a 100 hours grinding on "camel hump" or 305 heads that otherwise have horrible flow.

Comparing highly ported and modified racing heads on a racing engine to something that gets bolted on to a mild SBC isn't really apples-to-apples - especially when the big flow numbers come at .500 - .600+ lift! :-)

"i felt that the flow i got from the 1.84 valve was crap on my first head"
"i had 80 hours each in my 186's"
- Jeff Swisher

The best buy for a mild SBC are still Vortecs without question. But at this build level, still not really worth the investment IMHO - especially before making sure the engine is basically healthy.

...and regardless, a head swap without a cam swap will result in net zero power gain...

[AcampoDave]

https://67-72chevytrucks.com/vboard/...d.php?t=796471 dialing in the timing on my 283 was cheap and effective. https://67-72chevytrucks.com/vboard/....php?p=9129708 and so was dialing in my AFR. In fact that one really woke it up.

[Backpayne]

Thank you all for the information! It is much appreciated.

I noticed a "canister" attached to the back of the block under the intake. Is that something that needs to stay in there? I assume it's something like a pcv?

Also, I would like to confirm that 305 heads will work with any sbc intake manifold, specifically the Edelbrock performer?

[Tom]

Originally Posted by Backpayne

Also, I would like to confirm that 305 heads will work with any sbc intake manifold, specifically the Edelbrock performer?

Vortec's require specific intake. TPI 305 heads like the castings listed above are standard intake pattern.

[AcampoDave]

Originally Posted by Backpayne

Thank you all for the information! It is much appreciated.

I noticed a "canister" attached to the back of the block under the intake. Is that something that needs to stay in there? I assume it's something like a pcv?

Also, I would like to confirm that 305 heads will work with any sbc intake manifold, specifically the Edelbrock performer?

The breather baffle doesn't have to stay if you plan on updating the valvecovers. I took mine out, put a freeze plug in the draft tube hole by the distributor and put later style valvecovers with a pcv on one side and a breather on the other. I wasn't crazy about losing the old school non-vented valvecovers with the script on them, but I wanted a pcv, and I wanted full roller rockers, (for whatever little gain they offered), and therefore needed taller covers anyway.

Edit: On my stock 283 I left that baffle in there and put a pcv valve with a grommet in the old draft tube hole. I've seen other threads where they sneak a pvc hidden on the back of the valvecover by modifying it, but never tried it.

[AcampoDave]

Originally Posted by Backpayne

Thank you all for the information! It is much appreciated.

I noticed a "canister" attached to the back of the block under the intake. Is that something that needs to stay in there? I assume it's something like a pcv?

Also, I would like to confirm that 305 heads will work with any sbc intake manifold, specifically the Edelbrock performer?

As detective Columbo used to say..."There is one more thing",....if you plan on using a squarebore carb like an Edelbrock, look at the Performer EPS since it's made specifically for that application. That way you can avoid the old Quadrajet style manifold plenum.

[MikeB]

Originally Posted by AcampoDave

....if you plan on using a square bore carb like an Edelbrock, look at the Performer EPS since it's made specifically for that application. That way you can avoid the old Quadrajet style manifold plenum.

Yes, the 2701 EPS would be a good choice. But a regular old 2101 Performer works well, too. No shims needed with an Edelbrock carb.

That said, the Holley/Weiand 8120 Street Warrior may be a better choice, because it's a newer design with lots of attention paid to equalizing runner-to-runner flow.

[GASoline71]

Originally Posted by AcampoDave

As detective Columbo used to say..."There is one more thing",....if you plan on using a squarebore carb like an Edelbrock, look at the Performer EPS since it's made specifically for that application. That way you can avoid the old Quadrajet style manifold plenum.

The EPS is such an underrated intake manifold. I had one on a 350 in a '79 K25 with a Holley 1850 600 CFM carb and had a cam profile ground from a local cam shop that matched the Comp XE268, and it made great power with good low-end grunt.

Gary

[geezer#99]

That ‘canister’ (its a baffle) sits up kinda high and some intakes won’t clear it.

[MikeB]

I think RustyPile is probably kidding, but not all 283 blocks could be safely bored to 4", even when new.

The cannister is part of a crankcase ventilation system, from breather to road draft tube. Google is your friend to learn about it.

After a compression check, I'd simply change the spark plugs, oil & filter, and try to start the engine. If no excessive valve train noise, drive it for awhile. Might want to check the carb internals, too.

As for 305 heads, #416 and #601 castings from the Z28 HO engines probably work better than stock 283 heads. There's talk about these on Chevy forums like NastyZ28 and GBody.

[RustyPile]

Originally Posted by MikeB

I think RustyPile is probably kidding, but not all 283 blocks could be safely bored to 4", even when new....................

I got out of the military in Feb, 1966. I immediately made plans to "restart" my racing endeavors. It was a common knowledge that 283 blocks made before 1959 could be bored .125" producing a 4" bore. The rules at the time were a "loose" weight per cubic inch limit. Actual displacement wasn't a factor, only the engine's designed displacement.. In the class I competed, stroking wasn't allowed.. The formula they used gave the 283, aka 301, a tremendous weight break over a 327. As I stated, it also allowed much larger valves. Boring a 327 to even .060" over was a risky task.. I built for myself and fellow racers, numerous 301s using 283 blocks.. I still have a 4" 283 block... It's a pre-'58, as there are no motor mount bosses in the side of the block..

[MikeB]

Originally Posted by RustyPile

It was a common knowledge that 283 blocks made before 1959 could be bored .125" producing a 4" bore. The rules at the time were a "loose" weight per cubic inch limit. Actual displacement wasn't a factor, only the engine's designed displacement.. In the class I competed, stroking wasn't allowed.. The formula they used gave the 283, aka 301, a tremendous weight break over a 327. As I stated, it also allowed much larger valves.

I certainly remember the 301 craze, but wasn't sure which year blocks would work. In the late 60s I actually bought a 283 block that had been bored to 4". When I took it home and pressure washed it, I discovered a crack in the lifter valley, probably from someone running little to no antifreeze. I then took it back to the junkyard and got another 283 block.

I wanted to go to 4", just to say I had a 301, but the machinist talked me out of it, so it became a 292. With Power Pack heads and stock valves, a 301 probably wouldn't have worked any better. Wish I could remember all the parts, but I do recall it having domed pistons and some kind of Isky or Erson cam. Oh, and Hedman 4-into-2 headers!

[RustyPile]

Originally Posted by MikeB

I certainly remember the 301 craze, but wasn't sure which year blocks would work. In the late 60s I actually bought a 283 block that had been bored to 4". When I took it home and pressure washed it, I discovered a crack in the lifter valley, probably from someone running little to no antifreeze. I then took it back to the junkyard and got another 283 block.

I wanted to go to 4", just to say I had a 301, but the machinist talked me out of it, so it became a 292. With Power Pack heads and stock valves, a 301 probably wouldn't have worked any better. Wish I could remember all the parts, but I do recall it having domed pistons and some kind of Isky or Erson cam. Oh, and Hedman 4-into-2 headers!

As you know, it takes a bunch of RPM for "small engines" to keep up.. The advantage that extra .060" gives you over a 292 is big 2 inch intake valves will clear the top edge of the cylinder.. The 301s I built all had the fuelie heads - 2.02 intakes and 1.70 exhausts, they almost touch.. Stuff the combustion chamber full of piston dome, upwards of 12.5 - 13:1.. .500 lift. 300 - 310 actual duration and lots of overlap to aid scavenging.. Finish it off with the best rods money can buy.. Gear it to run 7900 - 8300 (8500 - 8600 on occasion) at the end of the straightaway, you'll definitely need some good valve springs to do this.. The cams I used back in those days were Reed Cams, ground specifically for short dirt tracks..

[AcampoDave]

It has been my understanding that the 305 vortec engine did not use "vortec" heads per se as found on the larger engines. Even though GM began calling the whole 305 motor a vortec, the heads were were not truly "vortec heads".

[theastronaut]

Vortec heads will need center bolt valve covers in addition to a Vortec specific intake. The valves will be shrouded in a small bore 283 and compression will drop so they won’t flow as well as they would on a 4” bore, and the improved chamber design is kinda wasted at a lower compression point.

The 416 and 601 heads flow better than the old 283 Power Pack heads, have small chambers to keep compression up, and use standard intakes and perimeter bolt valve covers. No downsides to using them on a 283. With mold port work they’ll make really nice power.

Vortec 305 heads do not carry over the same port and chamber design advantages that 5.7 Vortec heads have.


I bought a 283 a few months ago and just went over researching all this myself, to the point of picking up a set of 601 heads. Since then a neighbor offered me a complete running Vortec 5.7 for free, and a friend has a large journal 327 crankshaft so I might end up building a roller cam 327 instead.

[MikeB]

Originally Posted by theastronaut

I bought a 283 a few months ago and just went over researching all this myself, to the point of picking up a set of 601 heads. Since then a neighbor offered me a complete running Vortec 5.7 for free, and a friend has a large journal 327 crankshaft so I might end up building a roller cam 327 instead.

Sounds like a good plan! I always loved those 327s. Even the 300hp version was a great all-around engine.

Several years ago I built a 327 for a 55 Chevy sedan. I used a 350 "010" block, 307 crank, Brodix IK180 heads, and a moderate solid lifter cam. Along with a Muncie 4-speed, it was like I was a kid again!

Your large journal 327 crank was a real find. They were only made for what, a year or two? I almost bought a forged 327 crank, but it would have been a real budget buster. Have fun!

[Tom]

Originally Posted by theastronaut

Vortec heads will need center bolt valve covers in addition to a Vortec specific intake. The valves will be shrouded in a small bore 283 and compression will drop so they won’t flow as well as they would on a 4” bore, and the improved chamber design is kinda wasted at a lower compression point.

Your talking 350 vortec heads. I refferred to 305 versions. Smaller chamber, smaller valves, vortec ports.

[AcampoDave]

Soooooo....Mr Backpayne, any updates?