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WTB un-ported, rebuildable #18 Pontiac heads.

These were 1968 350HO heads.

Anybody here have some for sale or know where a set might be ?
 

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Wonder why the '69 350HO heads (#48's) were 2.11/1.77, but the '68 350HO heads (#18's) were 1.96/1.66. Funny how even the Edelbrock 87cc Round Port only used 1.66 exhaust valves, and all this time I thought if they were not 1.77 then keep looking.
 

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I think all Pontiac D-port heads after '71 had 1.66 exhaust valves. 455 heads included.

Most Pontiac factory cams were dual pattern, with at least 10° more exhaust duration than intake duration. So, by having the exhaust valve open longer, the 1.66 valves probably had plenty of flow.

As for the '68 350HO, Pontiac probably figured that a 350 really didn't need 2.11 intake valves. Also, for the '69 350HO, the block needed bigger cylinder chamfers, to unshroud the larger valves. There was not a big increase in the hp rating from '68-'69. They probably figured it wasn't worth the extra expense of using the big valve screw-in stud heads, on a 350. For the next few years, they didn't even offer a 4-barrel 350. When they did offer a 4-barrel 350 again, they used small valves, such as in the '73-'74 #46 heads.

Then they switched to 2.11 intakes with 1.66 exhausts. The 6x-4 350 heads have been very popular for lager cube builds. They were also used on '77-'79 W72 400's.

There have been lots of quick 350 powered drag cars, which used the small valve heads. Bill Rink did real good with his '74 GTO, in Stock. He now runs consistently in the high 10's with it, in Super Stock. Mike Morgan runs even quicker, with his 350 powered '77 Formy Super Stocker. Of course, it runs 6x-4 heads, with an 800 cfm Q-jet. So, it has a right to run a bit quicker.

Last year, there was a guy named Brad Koivisto who ran a quick '74 GTO Stocker. He was #4 on this qualifying list, with an 11.36. That's quick for a low compression 350 Pontiac powered Stocker.

https://www.dragracecentral.com/DRCStory.asp?ID=345815&Filter=30#indextop

As for the '68 350HO. I've never known of anybody to run it in a Stock or SS drag car. A guy named Adam Strang runs a mid 10-sec '68 400 Bird Stocker. He got some forged 350 pistons made, and approved by NHRA, for Stock class competition. Was considering building a 350HO & trying it in his car. Don't know if he still plans to do it or not.

Anyhow, my engine guy is trying to locate a set of #18 heads, for a possible 350HO Stocker build. Haven't discussed all the details with him. Just trying to help him find a set of usable #18 cores.
 

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do you have any idea what they used the #17 heads on in 68 they have the 2.11 / 1.77
Sorry, but the #17 heads had press-in studs & small valves, from the factory. If you found a set with 2.11/1.77 valves, somebody put them there, AFTER the car came from the factory. They came with 1.96/1.66 valves. Looks to me like the only difference in the #17 & #18 heads is the size of the combustion chambers.

http://classicpontiac.org/FAQ.asp?myPage=V8HeadInfo

#17 heads came on 350 2-barrel engines.

http://www.wallaceracing.com/enginesearch4.htm
 

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Talked to a guy in MA that has lots of Pontiac engine parts at a shop. Be back up there in a few weeks and I'll ask. Met him at the car show get together and he just told me where his garage was so I'll stop by while cruising before putting the car away for winter.
 
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