305 vs. 283 vs. old 283

Slight change of plans,thinking seriously about a SBC for my project..easier fit,cheaper,blah,blah,blah...In the garage sit 3 of them...a real '57 283 pulled out of a ragged 40 coupe many years ago,condition unknown,another 283 out of a '66 Nova with a PG,last run 30 years ago,been in dry storage since then,and lastly,a junkyard '78 305 with a Turbo 350,was running recently,don't know how well,was just pulled out of a police call tow...

I'd like to use the '57 heads,with the stagger bolts,on one of the other engines..

Can I do that?
I hear yes,and I hear no...
The Nova 283 may be the best choice,and it's already got the shorter oil filter,and the right pan,etc. and will fit the easiest..

Any problems mixing all 3? Nova block,earlier heads,and the T350?

What about compression? I heard from one guy that using those heads on the 305 would give me something like 9.5 to 1 ...so I will need dished pistons to make it work on shitty gas?

So many questions,so little knowledge ( me)

Thanks,Bill

 

I'm not at the location of the engines now,but is that correct about the 66 Nova oil filter mount?Is it higher on the block for clearance compared to other SBC?

 

Willie,

If you do a search on 283 builds....there's plenty of info on power Pack heads, STD heads and 305 heads.

Rat

 

Oil filter location same on all the small blocks. The 66 Nova should have a front sump pan. Mid 80s engines dip stick was moved to pass side diff pan then AIRC.

 

nova motors did have a diff oil filter. more recessed or somthing. dunno know first hand, dont have one tho.

 

Either late 70's or in 1980 the dipstick went to the right side. 9.5 comp will be fine as long as you use your head when you buy gas and or set the timing. If the heads off the 305 are HO they have bigger valves and will breathe better than standard 305 heads.

 

since you asked, i would run the later 283. as it is. clean it up and bolt it in

 

Of these three engines, definitely use the 66 Nova engine. The early Nova V-8s (till 67) had a block that differed from other Chevy small blocks in that they had an extra different boss for the clutch pivot ball, which makes no difference to you, but they were actually thicker through the main bearing webs (stronger), and they did have an oil filter mounting boss that was higher up in the block so the oil filter would clear the Chevy II/Nova clutch linkage, if so equipped. Didn't matter if your engine was stick shift or automatic-equipped from the factory...the engines all had these features.

But the two biggest reasons for using the 66 block instead of the 57? The 66 block has the bosses for side engine mounts, the 57 does not, and the 66 block uses a neoprene rear main seal, the 57 uses a rope rear main seal. Why use the 57 heads? The 66 heads are a better casting, and if the only reason is so you can use stagger-hole valve covers (the 57 heads)...unless you currently have in your possession some killer old-school valve covers with stagger holes, it ain't worth it. All passenger car 283 heads from 63 to 67were of the "power pack" style...they had 64cc chambers and decent port sizes. If your 57 heads are not power pack heads, they're dogs...bigger chambers (low compression) and TINY ports. Besides, I'll bet half the guys on here couldn't tell a 55 265 from an 87 350 if you painted 'em both Chevy orange and dressed 'em the same visually.

For lots of info on Chevy blocks, heads, and cranks, check the mortec web site...it identifies casting numbers and gives specs.

I'd stay away from the 305...small bore, heads don't easily interchange. Also, the 305 is gonna have the center bolt valve covers...those aren't as cool looking. Good luck with your project!
Craig

 

centerbolts started in 87-89, his 305 is a 78. should be standard valve covers

but the rest is what i was thinkin. the 66 is yer best choice

 

The only real reason to use a '57 block would be if you were being very strict about not using any parts built after a certain year, but since you're talking about running a TH350 anyway, just use the '66 block--it should be able to use a block mounted starter no problem, whereas the '57 block may not even have enough meat in the starter mounting area to be drilled for one. Run 1957 power pack heads if you want, but the first thing that people in the know about early vs. late sbcs (like me) will do when they see the early valve cover pattern is look at the block to see if it has side mounts. Of course, '58 283s had side mounts and stagger bolt valve covers.......

 

283's are killer little motors. Skip the 305.

 

If you decide on the '57 block, you can use the TH350. You will need an adapter that allows you to bolt the starter to the bellhousing. Also; use bellhousing mounts. Most tri-five vendors sell these parts.

 

Since the '57 283 and the '66 Nova 283 are both probably a rare item to a "gold chainer" collector that demands "numbers matching" I would not use either one,the bucks you could probably get for them should buy you a nice built 350 or 383.You just need to cruise the websites these people hang out on and post the adds listing the casting numbers.If you need to do a build now,use the 305.

 

Craig,the earlier 305's are not center bolt, I just sold a pair of 601 castings 3 weeks ago,it's not uncommon for guys to put these on 350's to raise compression, the valve sizes are 1.84's and 1.5's.

 

283 may have side mounts in 57 and like it was said, centerbolt vc's are an 80s thing.

 

raised compression , but crappy ports and tiny shrouded valves
crack prone -thin smogger casting -305 is death

 

'57 283's had front mounts.

 

That does not apply to all casting numbers,there were 350 heads that were also thin and would crack and several years that had problems with rocker studs pulling loose.The 416 and 601 305 H.O. castings will out flow the old "Power Packs", back in the day,they used terms to kick up the marketing hype too,the so called power pack head with the single pyramid marking was on a lot of 2 bbl motors,Ford put "Thunderbird Special" on early 292's,it sounded cool but it was just hype too.

 

Thanks to all..as usual,good info on the HAMB...appreciate the responses

 

He's (original poster) talking the staggered perimeter bolt valve covers, not center bolts. I thought this was an old car forum...cant believe the number of people missing this.

 

my 57 283 had a th350 on it and no adapter, starter mounted like usual. no side mounts, had front mounts and bellhousing mounts

 

missed what? 1 person said that the 305s had centerbolts, and 2 corrected it.

 

That's what i did:

 

Two people corrected the guy and said that early 305 heads didnt have centerbolts...nobody mentioned that the OP was talking about stagger bolt, not center bolt. Since you were one of the centerbolt people now you feel you must defend your post. Now I see why I leave for months at a time...come back for a few days, and leave again.

And to the post above: LOOKING GOOD!!!

 

its was mentioned early that the staggered bolt heads wouldnt be the best choice(smaller valves and ports), unless he had some nice covers that he really wanted to use. the later heads would be the best choice. dont come into a thread and act like everyone is an idiot

 

Your right. The adapter plate I was talking about is for the '55-'56 265 Chevy.

 

lol, after i said that i had to go check, just to make sure

 

58' was first year for side mount on sbc. the 57' block and 66' block are worth good money these days to a person doing a resto.