Pontiac - Street No question too basic here!

          
Reply
 
Thread Tools Display Modes
  #1  
Old 12-11-2017, 12:03 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default 6X-8 Heads - CC at 109 ???

I acquired a 455 motor with 6X heads while looking it over I noticed that both heads have been stamped 109 CC. That seems to be a large chamber volume for 6X-8 heads. My other set came back at 101 CC after valve job. So questions: How do you get 109 CC from 6X-8s? The heads have been worked on supposedly by a Pontiac shop. Any one know what shops stamp the CCs on heads?

  #2  
Old 12-11-2017, 12:05 PM
gtofreek's Avatar
gtofreek gtofreek is offline
Ultimate Warrior
 
Join Date: Feb 2007
Location: Tucson, Az.
Posts: 7,494
Default

I had a set CC at 106.

__________________
Paul Carter
Carter Cryogenics
www.cartercryo.com
520-409-7236
Koerner Racing Engines
You killed it, We build it!
520-294-5758

64 GTO, under re-construction, 412 CID, also under construction.
87 S-10 Pickup, 321,000 miles
99Monte Carlo, 293,000 miles
86 Bronco, 218,000 miles
  #3  
Old 12-11-2017, 12:21 PM
steve25's Avatar
steve25 steve25 is offline
Ultimate Warrior
 
Join Date: May 2008
Location: Westchester NY
Posts: 17,511
Default

I valve job in conjunction with Tulip face valves and or some unshrouding work will do that when you start off with 98 CC to 101 CC head.

__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs!
And he was not talking about 1/8 or 1/4 mile ETs!

1) 1940s 100% silver 4 cup tea server set.

Two dry rotted 14 x 10 Micky Thompson slicks.

1) un-mailed in gift coupon from a 1972 box of corn flakes.
Two pairs of brown leather flip flops, never seen more then 2 mph.

Education is what your left with once you forget things!
  #4  
Old 12-11-2017, 01:47 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

Are Tulip face valves usually stock valves? About to pop the valley pan and look around. I guess the looking for the exhaust seal on valve will identify a stock valve? Any other way to spot a stock valve?

  #5  
Old 12-11-2017, 02:10 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

Thanks good to know about the CC on the heads. Going to pull current cam to see what it is. Hoping to get a bore scope to check piston tops.

  #6  
Old 12-11-2017, 02:26 PM
GRX's Avatar
GRX GRX is offline
Ultimate Warrior
 
Join Date: Jul 2006
Location: Maryland
Posts: 1,400
Default

If you are popping the valley pan off safe to assume the intake has been removed. Use a small mirror and flashlight to look down the intake ports.

  #7  
Old 12-11-2017, 03:26 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

Intake and valley pan now removed, thanks for the tip on the mirror. I'll check it out. Motor looks clean, cam doesn't seem to have much wear. Should be pulling it later today. Then the dreaded "what cam should I use", depending on what I found.

  #8  
Old 12-11-2017, 06:04 PM
Skip Fix's Avatar
Skip Fix Skip Fix is offline
Ultimate Warrior
 
Join Date: Dec 1999
Location: Katy,TX USA
Posts: 21,706
Default

Ones I have are 105 but the "eyebrows" in the chamber are smoothed. My original 78's motor are 97.5.

__________________
Skip Fix
1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever!
1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand
1965 GTO 4 barrel 3 speed project
2004 GTO Pulse Red stock motor computer tune [email protected]
1964 Impala SS 409/470ci 600 HP stroker project
1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs
1964 Corvette Coupe 327 4 speed
  #9  
Old 12-12-2017, 12:03 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

well, I'm going to pull the heads and CC them to be sure they are still 109CC. Also going to elongate the push rod holes while there off and check spring pressure. I don't have a spring tester, should I bring the head to a machine shop and have the spring pressure tested?

  #10  
Old 12-12-2017, 12:09 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

Also the motor has a few issues, no wonder there is not much run time. It had some old 1.65 Erson roller rockers on it but the pushrods were rubbing the heads. If 109CC head then compression lower than I like. But what got me, someone had installed a 305H cam with that compression?

I just want to get the car on the road so I might just use a 2801 cam that I have on the shelf and not pull the heads.

This motor was supposed to be ready to run. Saw it running in car and thought I would drop in my car to get me going. After checking this motor over it has some issues.

  #11  
Old 12-12-2017, 12:10 PM
gtofreek's Avatar
gtofreek gtofreek is offline
Ultimate Warrior
 
Join Date: Feb 2007
Location: Tucson, Az.
Posts: 7,494
Default

Quote:
Originally Posted by 455GRIN View Post
well, I'm going to pull the heads and CC them to be sure they are still 109CC. Also going to elongate the push rod holes while there off and check spring pressure. I don't have a spring tester, should I bring the head to a machine shop and have the spring pressure tested?
Yes. They can also check for coil bind, and see how much they can shim to get pressures right if they are not already.

__________________
Paul Carter
Carter Cryogenics
www.cartercryo.com
520-409-7236
Koerner Racing Engines
You killed it, We build it!
520-294-5758

64 GTO, under re-construction, 412 CID, also under construction.
87 S-10 Pickup, 321,000 miles
99Monte Carlo, 293,000 miles
86 Bronco, 218,000 miles
  #12  
Old 12-12-2017, 12:19 PM
steve25's Avatar
steve25 steve25 is offline
Ultimate Warrior
 
Join Date: May 2008
Location: Westchester NY
Posts: 17,511
Default

I just reread your post here and it seems your are going by what the heads have been stamped in regards to the CCs since it seems you still have them bolted on the motor.
If it where me I would pull them while changing out the Cam to confirm there CC's and to maybe Mill them to get them down to 101 CCs.

__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs!
And he was not talking about 1/8 or 1/4 mile ETs!

1) 1940s 100% silver 4 cup tea server set.

Two dry rotted 14 x 10 Micky Thompson slicks.

1) un-mailed in gift coupon from a 1972 box of corn flakes.
Two pairs of brown leather flip flops, never seen more then 2 mph.

Education is what your left with once you forget things!

Last edited by steve25; 12-12-2017 at 12:24 PM.
  #13  
Old 12-12-2017, 04:06 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

Part of me wants to throw the 2801 cam in and go since I have the cam. But I really want to do it right. Its only a few more bolts to remove the heads now so I'm going to have them checked out and do it right.

  #14  
Old 12-12-2017, 04:08 PM
steve25's Avatar
steve25 steve25 is offline
Ultimate Warrior
 
Join Date: May 2008
Location: Westchester NY
Posts: 17,511
Default

Good, that's the best way to do it!

__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs!
And he was not talking about 1/8 or 1/4 mile ETs!

1) 1940s 100% silver 4 cup tea server set.

Two dry rotted 14 x 10 Micky Thompson slicks.

1) un-mailed in gift coupon from a 1972 box of corn flakes.
Two pairs of brown leather flip flops, never seen more then 2 mph.

Education is what your left with once you forget things!
  #15  
Old 12-12-2017, 04:44 PM
Skip Fix's Avatar
Skip Fix Skip Fix is offline
Ultimate Warrior
 
Join Date: Dec 1999
Location: Katy,TX USA
Posts: 21,706
Default

If you mill them 0.050 or more you have to mess with intake and valley pan sometimes.

I have a 2801 in a low compression 400 and it runs well for a stock type cam.

__________________
Skip Fix
1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever!
1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand
1965 GTO 4 barrel 3 speed project
2004 GTO Pulse Red stock motor computer tune [email protected]
1964 Impala SS 409/470ci 600 HP stroker project
1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs
1964 Corvette Coupe 327 4 speed
  #16  
Old 12-13-2017, 05:42 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

[ATTACH]Click image for larger version

Name:	domed pistons.jpg
Views:	132
Size:	46.1 KB
ID:	470018[/ATTACH]

Took the heads off, domed pistons, that changes everything.

Anyone seen a dome like this? any idea on CC?
Attached Thumbnails
Click image for larger version

Name:	20171213_150233.jpg
Views:	195
Size:	44.7 KB
ID:	470019  

  #17  
Old 12-13-2017, 05:43 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

I wiped one down looking for numbers, didn't see any. The others look oily. any ideas?

  #18  
Old 12-13-2017, 08:12 PM
Indianhead Indianhead is offline
Junior Member
 
Join Date: Oct 2008
Location: Portland, TN
Posts: 18
Default

The largest I can remember from yrs ago were 15cc most were 8-12cc. I don't recognize those in particular but that may get you in the ballpark of a cr range without cc-ing them.

  #19  
Old 12-13-2017, 08:40 PM
455GRIN 455GRIN is offline
Senior Member
 
Join Date: Jul 2005
Location: D/FW TX
Posts: 195
Default

Just from looking at some pics from Summit, these appear to be Keith Black KB-347 pistons. If I'm reading it right there are zero CC. Still need to CC the head but if its 109CC that is about 9.5 to 1 comp? From the pics about something wasn't happy, really oily pistons tops.

  #20  
Old 12-14-2017, 07:14 AM
steve25's Avatar
steve25 steve25 is offline
Ultimate Warrior
 
Join Date: May 2008
Location: Westchester NY
Posts: 17,511
Default

Do the Pistons rock in the Bore?

Do the back side of the Intake valves look oily?

What do the heads have for valve seals , white Telfon type's?

__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs!
And he was not talking about 1/8 or 1/4 mile ETs!

1) 1940s 100% silver 4 cup tea server set.

Two dry rotted 14 x 10 Micky Thompson slicks.

1) un-mailed in gift coupon from a 1972 box of corn flakes.
Two pairs of brown leather flip flops, never seen more then 2 mph.

Education is what your left with once you forget things!
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 05:24 PM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017