|07-20-2012 08:45 AM|
These guys are speaking the truth. It is NOT a 400. Sorry. For future reference, ALWAYS "run the numbers" when you buy something, ESPECIALLY a remanufactured engine that's out of it's "prime" (those engines were being rebuilt en masse in the late '70s, early ''80s). Today, there is virtually NO "expertise" on the Pontiac in any "rebuilder". You must go to a specialty shop.
670 heads are indeed, 14 degree/closed chamber. They have a very good intake runner. They also have massive "potential". Gene Kinch's "Gallopin' Goat" goes 9.80s right at 3,100 lbs. using 670s on a 462 CID "stock" block (.030 over 455). No adders. A TON of port work in them though. The large valve heads are not recommended for 326 or 350 blocks due to smaller bore size.
Bill's car is ******! Like most other Pontiac racers, after he makes a pass, the "locals" are betting on how "big" the big block Chevy in it is... Nope. Not a Chevy... (:- Big-power Pontiacs are "back" now that the aftermarket has stepped up.
|07-19-2012 11:00 PM|
|07-19-2012 10:59 PM|
|67pontiac400||I have started it and it ran great. Just needed a little carb tuning. Unfortunately the block was bought 12 years ago. I still have the receipt but I'm pretty sure returning it would be out of the question.|
|07-19-2012 10:06 PM|
It doesn't sound as though you've started it up yet, so if you bought it from PB, take it back and get what you paid for!!
If you go and cam it as if it were a 400 it could be a pig- a 'hot' cam in a 400 will be too much in a 350. The idle will be rough, it will make less vacuum so power brakes might not work right (or at all if the cam's radical enough), the bottom end power (what a Pontiac does best) will be lost and it will be an unsatisfactory engine all the way around.
|07-19-2012 09:49 PM|
|67pontiac400||By the way. NICE CAR!! 65??|
|07-19-2012 09:48 PM|
|67pontiac400||I'm going to be running E85. It's plentiful in NY. Any advice as to what valve springs to use? I' going to assume I do have a 400 so as to not get too stressed about paying $1000 for something I didn't order. And it came from pep boys too. What cam would be a good combination for my set up? Trying to get all I can out of it without spending too much.|
|07-19-2012 09:29 PM|
A picture of mine:
|07-19-2012 08:38 PM|
|67pontiac400||Oh. And they are also A.I.R 670 heads. I was planning on having some mill work done. Maybe hardened seats and a valve grind.|
|07-19-2012 08:22 PM|
|67pontiac400||I hope it displaces 400ci. That's what I paid for and paperwork I got with the motor says it's a 400. It's just the codes that don't make to much sence. I can't see the side of the block or get to the pistons to measure them. The motor is currently sitting in the car complete with my old 7h1 heads from my original 350 on it. Just trying to get a good combination of parts. A cam good cam and valve springs. Trying not to break the bank. Just paid $500 for the 670's. Everything I've read about them said they are good heads. And they have a lot of potential. I don't want to have to buy another set of heads in the future.|
|07-19-2012 08:10 PM|
|07-19-2012 08:07 PM|
Prolly ends w/"9".
C/N 9790079: 1968-'69 350
|07-19-2012 08:01 PM|
|67pontiac400||Casting numbers can't fully be read. This is what I can read 97???78?. The 670 heads have the closed chamber design. I read that the 670 heads do have the new valve angle.|
|07-19-2012 07:57 PM|
|cobalt327||I believe the factory 2.11 x 1.77 heads were all 14 degree. In any event the 670 will work on later shortblocks.|
|07-19-2012 07:21 PM|
|LATECH||Bill, arent the 670 heads the old closed chambered heads. If so they have the 22 degree valve angle not the 14 degree like the open chamber heads. Hope it has the right valve reliefs in the pistons.|
|07-19-2012 07:16 PM|
The J317 date code is October 31, 1967, so it would have been cast for the '68 model year making it a 350. A .060 over 350 would make it a 365 using the stock 3.75" stroke crank. I also looked up the '68 YN code and it is a 2bbl, 265 hp, automatic block and would have had #17 heads.
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