valve stems - Yellow Bullet Forums

Go Back   Yellow Bullet Forums > Technical Section > Naturally Aspirated - Uratchko Racing Engines

Naturally Aspirated - Uratchko Racing Engines

Reply
 
Thread Tools Display Modes
Old 03-20-2013, 11:29 PM   #1
634 Chevelle
Junior Member
Spooled up
 
634 Chevelle's Avatar
 
Join Date: Nov 2008
Posts: 207
Default valve stems

Has anyone had any trouble with valve stems flaking. They are manley titanium valves , bronze liners, no valve seals, no oil restricters. Seems to be mainly intake vavles. Motor is a634 bbc that has 2 stages of nos, 7500-8000 rpm, has never had any real problems other than a few lifted ring lands. Any input would be appreciated.
__________________
'66 Chevelle, 3000#, 634 bbc
1.11 60ft
3.08 330ft
4.71 660ft at 153 mph
7.32 1320ft at 186 mph
634 Chevelle is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 03-20-2013, 11:31 PM   #2
JakesPorting
Member
Pullin gears
 
JakesPorting's Avatar
 
Join Date: Sep 2009
Location: Maryland
Posts: 510
Default Re: valve stems

Exhaust valves ?
JakesPorting is offline   Reply With Quote
Old 03-20-2013, 11:42 PM   #3
634 Chevelle
Junior Member
Spooled up
 
634 Chevelle's Avatar
 
Join Date: Nov 2008
Posts: 207
Default Re: valve stems

I think a couple exhaust valves had some minor flaking but mostly was just intake
__________________
'66 Chevelle, 3000#, 634 bbc
1.11 60ft
3.08 330ft
4.71 660ft at 153 mph
7.32 1320ft at 186 mph
634 Chevelle is offline   Reply With Quote
Old 03-21-2013, 12:34 AM   #4
JakesPorting
Member
Pullin gears
 
JakesPorting's Avatar
 
Join Date: Sep 2009
Location: Maryland
Posts: 510
Default Re: valve stems

Ive seen quite a few exhaust but it was from heat .

I have seen some Intakes do it also above the guide near the top

of where the moly is fused to the stem and I think it comes from

the valvetrain not being happy as in floating, bouncing , springs

rubbing heads and retainers rubbing rockers .

Last edited by JakesPorting; 03-21-2013 at 12:35 AM.
JakesPorting is offline   Reply With Quote
Old 03-21-2013, 02:28 PM   #5
634 Chevelle
Junior Member
Spooled up
 
634 Chevelle's Avatar
 
Join Date: Nov 2008
Posts: 207
Default Re: valve stems

I believe it is the moly coating that is flaking,nothing in valve train is rubbing (jesel rockers), cam profile is easy on springs (.900 lift) and springs are checked regularly, could detanation cause it, the valves are 12 years old .
__________________
'66 Chevelle, 3000#, 634 bbc
1.11 60ft
3.08 330ft
4.71 660ft at 153 mph
7.32 1320ft at 186 mph
634 Chevelle is offline   Reply With Quote
Old 03-21-2013, 03:01 PM   #6
spray power
Senior Member
Smoked another BBC
 
Join Date: Nov 2007
Location: Hot Springs, AR.
Posts: 1,698
Default Re: valve stems

Have seen this with Manley, Victory and Stealth valves mostly.

Most of the reps have said they have fixed there coating problems and they are good now!

When we have seen this we have always replaced the valves, didn't want to take a chance on the coating getting between the valve and guide and haveing a problem or the stem seeing extra heat/where and failing... Good luck..
__________________
Auston Pasquith
ACP Race Cars & Custom Fabrication
Hot Springs, AR.
Custom manifold porting/EFI conversions
Dealer for:
Induction Solutions/ Woody's Pluming/Jerry Bickel Race Cars/RJ Race Cars/Race Parts Solutions/Hyperformance/BTE-Memphis Performance/Strange Eng./Schoneck Composites and more!
spray power is offline   Reply With Quote
Old 03-21-2013, 07:47 PM   #7
634 Chevelle
Junior Member
Spooled up
 
634 Chevelle's Avatar
 
Join Date: Nov 2008
Posts: 207
Default Re: valve stems

Thanks for the info
__________________
'66 Chevelle, 3000#, 634 bbc
1.11 60ft
3.08 330ft
4.71 660ft at 153 mph
7.32 1320ft at 186 mph
634 Chevelle is offline   Reply With Quote
Old 03-23-2013, 04:16 PM   #8
ranger
Member
Pullin gears
 
Join Date: Dec 2007
Location: Iowa
Posts: 531
Default Re: valve stems

Yeah, bad problem with flaking on the exhaust valve right where the stem is exposed at the valve guide. Intake valves flake after awhile, looks like due to wear.
ranger is offline   Reply With Quote
Old 03-23-2013, 05:36 PM   #9
634 Chevelle
Junior Member
Spooled up
 
634 Chevelle's Avatar
 
Join Date: Nov 2008
Posts: 207
Default Re: valve stems

It was flaking intake valve stem where it runs in guide. Figured it started flaking due to 13 years of use
__________________
'66 Chevelle, 3000#, 634 bbc
1.11 60ft
3.08 330ft
4.71 660ft at 153 mph
7.32 1320ft at 186 mph
634 Chevelle is offline   Reply With Quote
Old 03-24-2013, 02:38 PM   #10
douglas
Senior Member
Smoked Another SBC
 
Join Date: Apr 2009
Location: USA
Posts: 8,351
Default Re: valve stems

It is the coating flaking off. For some reason, I've seen it be worse with Manley valves than several others. Manley actually replaced a few for me. BUT come on man, if you have been running the same set of valves for 13 YEARS, what do you expect?!!
douglas is offline   Reply With Quote
Old 03-24-2013, 03:22 PM   #11
634 Chevelle
Junior Member
Spooled up
 
634 Chevelle's Avatar
 
Join Date: Nov 2008
Posts: 207
Default Re: valve stems

Wasn't expecting anything just wondering if was missing something Valves are 13 years old but only 25-35 passes a year
__________________
'66 Chevelle, 3000#, 634 bbc
1.11 60ft
3.08 330ft
4.71 660ft at 153 mph
7.32 1320ft at 186 mph
634 Chevelle is offline   Reply With Quote
Old 03-25-2013, 09:39 AM   #12
Rodz
Senior Member
Smoked another BBC
 
Rodz's Avatar
 
Join Date: Feb 2008
Location: West Michigan
Posts: 1,373
Default Re: valve stems

Quote:
Originally Posted by 634 Chevelle View Post
Wasn't expecting anything just wondering if was missing something Valves are 13 years old but only 25-35 passes a year

After 13 yrs it time to replace flaking or not.
Rodz is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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



All times are GMT -4. The time now is 11:02 AM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Garage Plus vBulletin Plugins by Drive Thru Online, Inc.
Resources saved on this page: MySQL 2.86%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Yellow Bullet LLC