70 cc heads worth a crap?

[tracy]

MY HEADS ENDED UP BEING 70 CC CASTINGS #3927185. VALVES 1.72 AND 1.5 .
WOULD THESE BE WORTH HAVING DONE. BIGGER VALVES OR THEY STILL WOULDN'T FLOW ENOUGH?

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72 CHEYENNE 3/4 TON 4X4...14 bolt full float rear.4.10 gear and 350/350/np205 has a little needs a lot!

[Randy70C-10]

Depends on the size of the engine, cam, carburetor. You be OK if you're running a 283 with a 2 barrel carb, otherwise, they won't make much power.

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Yeah, that's right. My name is Randy too!
WWW.Randysrods.freeservers.com
1970 Chevy C-10 shortstep
30 Ford Model A Coupe 4 inch chop, 350, GMC 671 blower-Hell yeah it's fast!
87 Harley Sportster(couldnt get a 350 to fit)
Self Propelled Lawn Mower
Built in USA!!!!

Virginia Beach, VA.

[texnician01]

I'm gonna redo a set of 520 casting heads, 64 cc, with 1.94 intakes and 1.50 exhaust. putting in all new guides, hardened exhaust seats screw in rocker studs and use them on my 327. should cost between 400 and 500 for all of the head work. the guy that is going to do the work on them at the local machine shop does all kinds of racing cars and he said that they should do pretty good as far as flow. of course not as good as a set of voretc heads the everyone has told me about so far. but if you want to keep it original or close to, then I'd use the heads you have, they are heavy casting heads with small chambers. I wouldn't put them on a 350 cause your comp. would be too high but on a 283 or 327 they'd be fine. those prolly even have hardened seats in them.

Nathan

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1969 C-10 292 I-6 4 spd in the middle of a restoration. going to get a 327 and 3.07 gears but keeping all of the original parts so I can put it back to original later on down the road.
55 chevy 4 door 150
47 Willys CJ-2A

[Longhorn Man]

You sure about that? A 70cc head will drop the compression ratio.
I would go for the vortecs myself.

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'69 G.M.C. 350/350. Trying to clean up the left over damage from the Dope-Smokin-Old-Man
I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it.
FINALLY got the HORNIAC...a '70 one ton Longhorn with a Pontiac 350/350 and lots of 'personality'. Check out The Longhorn Webite.
If you need a pic posted, E-mail me at longhornmail@yahoo.com
My name is Andy...not Randy...I'm in Ohio...Not Illinois...close enough?
Columbus Ohio

[bigvinnie]

According to a chart in "How to rebuild your small block Chevy", compression ratio with a 70cc head would be around 9.8 on a 350 with flat top pistons...

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'72 short step, 350, 700R4, tilt, ps, pdb, a/c, lowered coils, etc., other work in progress... San Diego, CA
http://www.ixpres.com/vlusardi/chevtrk.htm

[69 longhorn]

A 70cc chamber head will drop ratio. As a rule I have seen a 64-66 cc head run in the 9.5 -9.7 range on a flattop 350(a lot depends on deck height,& head gasket thickness). My 383 has 70cc Edelbrocks to keep the comp ratio @ 9.8 with flattop pistons(its square decked,but not to min spec on quench). I think dollar for dollar,the Vortecs are a "good bang for the buck"........unless you want that original/numbers match deal. Good luck.......69longhorn.

[bigvinnie]

same chart says a 64cc head would yield a ratio of 10.3 on a 350 with flat tops...

[69 longhorn]

Not unless everthing is decked to minimum spec,the factory also says 10.25 or 10.5 on the 300hp 350........but they arent that high with factory deck clearance.......69

[Fast68Chevy]

1962-67 3854520 327 1.72 1.5
1962-67 3884520 283,327 1.72 1.5

if you donr end up using the 185 heads, then at least dont scrap them, save them for somone who would port them and instlal larger valves, they are heavy cast good heavy heads


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Randy- Lincoln, IL
randy@ccaonline.com 2177353230
*many GM parts bought, traded, or sold -am parting out: '81 Cutlass Supreme Brougham

current fleet: -71 C-10 350/CH465/3.07- basketcase, #1
-90 Cavalier 2.2L sky blue, a driver
-84 Z28 5.0L/700R4/3.73 daily driver
-84 Firebird/SE 2.8L/T-5/3.73/engine bad, project #2
-82 purple Trans Am, project #3
*Paint is overrated*
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[tracy]

WELL I ALSO GOT A SHOT AT A PAIR OF 14102193. WITH A FRESH 3 ANGLE JOB ON THEM??????????WOULD THE 70 CC BE THAT BAD ON A 350 IF WE UPPED THE VALVES? WOULDN'T COMPRESSION MAKE UP FOR IT?

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72 CHEYENNE 3/4 TON 4X4...14 bolt full float rear.4.10 gear and 350/350/np205 has a little needs a lot!

[bigjimzlll]

if you install larger valves make sure and un-shroud them...you can actually decrease flow with un-shrouded larger valves..Do some more research...ive been doing a ton lately..ive got 750.00 bucks in a set of 186 heads....adds up quickly...with vortecs you would have about the same, with all the other parts you would need, but they would flow better..im leaning towards the trick flow aluminum...about 900.00 complete..but they flow great

[texnician01]

fast,
I already know that they are 1.70 from the factory but I'm gonna put in 1.94's. and port em out a little.

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1969 C-10 292 I-6 4 spd in the middle of a restoration. going to get a 327 and 3.07 gears but keeping all of the original parts so I can put it back to original later on down the road.
55 chevy 4 door 150
47 Willys CJ-2A