SBC Head Casting # Question, And My New Score

[Homeresque]

Whats the diff between the 283 '896' and the 283 '520' heads?? Both are 1.72/1.5, 58cc, but my casting book calls the 520 the 'power pac' and not the 896. I have 896's that have not been run since rebuilt, and now 520's that would need rebuilding (mag, hardnd seats, new valves/springs/seals, 3 angle job). Is there any diff??

Friday I dragged home a '66 283 out of a nova/chevyII, complete less than 50k miles, intake and heads never been off, all dates jive up including the water pump! Unfortunately its a 2bbl.
Now I have to decide whether to deflower this beautiful virgin and build it as the snotty 307 I was intending to, or keep it a number-matching 2bbl 283, even has the goofy oil pan.

[porknbeaner]

Forget the 307, bore it .125 and build a 302. Better bore to stroke ratio. We actually called them a 301 until Chevy built 'em (Z-28) and called 'em a 302. They have excellent rev potential.

The power pac head had a double spring and the other didn't. They had a diamond cast into the end. I don't recall if there was any port difference or not. Snag a pair of calipers and check port size, then look inside for whoopdedoos. The only difference that I recall was the springs, but I could be mistaken.

if it don't make ay dirty it aint yours http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

[38Chevy454]

Just for info, that goofy oil pan is worth money. The Chevy II's require a front sump, and the pan and pickup are probably worth around $100 or so for swapping material. Many Chevy II owners want a V-8, and need that pan. Depending on what you paid for the 283, it might be even better to sell it to a Chevy II guy for profit and then buy a different engine. Also in back of my head i seem to remember that there is some other very slight difference in Chevy II blocks that make it more valuable for the Chevy II guys. Can't recall what that is though.

As for the heads, I have no idea. My understanding was the power pack heads were the four barrel version and non-power pack was for two barrel. Your 307 block is fine, it is a 283 bore with 327 stroke. Or put another way it is a 1/4 inch stroked 283. It has the larger diam con-rods as used in 68-up SBC's. The 307 will never be a tremndous fire-breathing engine. It needs more bore to be able to breathe better. It will be fine with your 283 heads, within limits. You can take a late model 350 block and put your crank to get a large journal 327.

[Homeresque]

Yea, the difference in the block is the oil filter pad is mounted about 2"s higher and the dip stick hole is plugged.

What I WAS thinking was making the 307 out of the 283 with a 327 crank I have laying around. Ive already decided to leave the 896s on the shelf, rebuild the 520s that I KNOW are powerpack, and leave it 283 (but .030 over) with dates matching. I'll keep the date matching 2bbl intake and water pump aside, go with a 4GC and a cam, drop some money on a dual-snorkel air cleaner and some orange spray paint and...

[porknbeaner]

That's doable. I like the orange paint part.

Be sure and not loose that oil pan. If nuthin' else you can hang it on the wall and call it art. http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

[Dan]

I'll take the goofy oil pan and pump pickup if your getting rid of them, they are what I need to put my SBC in my '49 ford - let me know if you are interested in getting rid of them, maybe we can make a deal.

[fab32]

Also the mounting hole for the clutch crossover shaft is in a different location on the Chevy II block. The oil pump has a front inlet hole vs the side hole on regular pumps. Might not make any difference today with everyone putting a wimpy automatic in everything but when they were new the '66/'67 chevy II w/a v8 (350hp/327 available) wouldn't be considered by anyone with BALLS if it didn't have a 4spd.

Frank