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probert
01-04-2004, 06:50 PM
The cylinder head numbers on my sbc are 3890462. Any charts I've seen say they are 2.02 valves with 64 cc chambers. I tried measuring the valves without removing them and they appear to be 1.94. Were both valve sizes available for these heads and if so are they indeed 64 cc chambers?
Thanks

Charley Lillard
01-04-2004, 07:12 PM
On 202's the valves will almost be touching each other while 194's will have about 1/8" between them. Welcome to the site and please fill out your Profile.

jg95z28
01-04-2004, 07:21 PM
According to Colvin, that head was available with both 2.02/1.60 and 1.94/1.50 valves. In 1966 they had 62.076 cc chambers in 1967 they increased to 63.305 cc.

Zman
01-05-2004, 11:53 AM
I have 2 sets of 462s, both are 194s

probert
01-07-2004, 04:53 PM
There's about 1/8" gap between the valves so it looks like they ARE 1.94's. This is a sweet running little engine and I originally just wanted to freshen up the bearings and rings. I'm pretty bummed to find out they aren't 2.02's....I'll be lucky if I'm getting 340 hp! Funny how the numbers can take the smile off your face :-(
Thanks for the help tho, appreciate it!

JoeC
01-07-2004, 05:19 PM
some castings can be converted to 202 valves.
check with your machine shop

Salvatore
01-07-2004, 06:01 PM
I wouldn't be bummed out if I were you. Until you saw the size of the valves you thought the engine ran real nice! It is almost impossible to feel the difference on the street with the bigger valves. Remember all 350cu. 300hp cars have the small valves, also all the 275hp-327 cars do too. Some of those low H.P. cars are running in the high tens,low 11's in Stock Eliminator. SO.....Be Happy! Sam http://www.yenko.net/ubbthreads/images/graemlins/3gears.gif

Supergas990
01-07-2004, 06:19 PM
My 67 Chevelle has the 275hp 327 in it with those heads on it. You'd be suprised how quick that thing winds up and takes of. http://www.yenko.net/ubbthreads/images/graemlins/shocked.gif http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif

Remember... BIGGER isn't always better!!! It's all in the combination. http://www.yenko.net/ubbthreads/images/graemlins/3gears.gif

Blair

probert
01-07-2004, 07:22 PM
I bought the car a couple of years ago, a 69 Firebird, not so much for the engine but the owner told me not to scrap it.Despite it's looks he assured me it was a strong runner, just needed some work.I tinkered with it, got it running and damned if he wasn't right, it's quick.I just recently tore it down and here's what it's got.It's a 355 with flat top pistons, a single plane Edelbrock intake, 600 Holley and a Comp Cams 274H cam.Behind it is a Saginaw 4 speed and a 355 rearend.
You guys are right, bigger isn't always better and the cam that I took forever to select has set off the combination nicely....300- 340 hp?? but I can't help wonder how many horses those 2.02's would add http://www.yenko.net/ubbthreads/images/graemlins/burnout.gif

Salvatore
01-07-2004, 07:48 PM
Hey Probert, Is the motor a chevy or a pontiac? Also the Saginaw is probably a 3.00 first gear. A lot of torque especially is it is a Pontiac motor. sam

jg95z28
01-07-2004, 08:47 PM
[ QUOTE ]
Hey Probert, Is the motor a chevy or a pontiac? Also the Saginaw is probably a 3.00 first gear. A lot of torque especially is it is a Pontiac motor. sam

[/ QUOTE ]Definitely a Chevy with the head castings he listed. Unless someone did some serious work on it. http://www.yenko.net/ubbthreads/images/graemlins/wink.gif As everyone else said, those are great heads and shouldn't be a hinderence for building a nice streetable small block.

probert
01-07-2004, 10:10 PM
Oh it's a Chevy alright......and I put lots of orange paint on it just so no one gets confused! http://www.yenko.net/ubbthreads/images/graemlins/haha.gif

Salvatore
01-08-2004, 12:26 AM
Ya, I know 462's are chevy, but the Firebird threw me a curve for a second. I wouldn't change those heads unless you have a set with screw in studs and guide plates, and they came with 2.02's installed. JMO Sam http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif