need a little help...

thewrench3 · 05-16-2008, 03:29 PM

Well I got the engine all apart today. The cam is ok. The intake valves are tuliped, sucked up into the intake ports. I am going to try to post a pic. Any ideas why? The old valves I had in it never did that. I ran them for two years.

SSDiv6 · 05-16-2008, 03:36 PM

Quote:

Originally Posted by thewrench3

Well I got the engine all apart today. The cam is ok. The intake valves are tuliped, sucked up into the intake ports. I am going to try to post a pic. Any ideas why? The old valves I had in it never did that. I ran them for two years.

Which brand of valves? Manley, SI, Ferrea,...????

Mark Lewis · 05-16-2008, 04:19 PM

too much timing or lean?

BillK · 05-16-2008, 07:53 PM

TW,

Something is causing the valves to get extremely hot. It could be anything in the combustion process. I have also seen it in marine engines when water gets into the cylinders through the exhaust but I doubt this would be the case here. Did you change anything during your "freshen up" that could keep the valves from dissipating heat ? Like a much narrower valve seat than you had before ? Anything else change in your combination ? Not enough timing can be just as bad as too much. Vacuum leak ?

Just thinking out loud

mtkawboy · 05-17-2008, 01:13 PM

If the valves were sinking in the head wouldnt the lash get tighter not looser?

thewrench3 · 05-17-2008, 03:24 PM

Yes the valve lash would go to zero.
After, i put new rings, bearing and gaskets thats when the problem occurred. I use a .070 wide valve seat width. But the old valves were the same way. I changed to a thinner head gasket to try and get a llittle more compression.
I had always used manley valves in the past. Never had a problem with them. These valves were a no name brand.
I am thinking that I am running to lean, the exhaust gas temperature is 1400 deg. in high gear. I run 32 degrees total timing, that seems to be the limit with my combination. It runs slower e.t and mph with more timing.

SSDiv6 · 05-17-2008, 07:41 PM

Quote:

Originally Posted by thewrench3

I had always used manley valves in the past. Never had a problem with them. These valves were a no name brand.

Go back either to a Manley or Ferrea valve. Low cost valves made overseas tend to be softer. I have checked lower cost valves for hardness in the past, and there is a difference. Quality control for materials and processing is not the same with overseas made valves that are mass produced. They cannot sustain lean conditions and the higher spring pressures used in racing.

gmonde · 05-17-2008, 07:47 PM

two years ago we had a ford v6 in the shop,same deal intake tuliped also did the exhaust valve in as well ,found that it had a bad crank sensor caused timing to retard and they ran it hot ,check the timing,maybe the bump in compression was enough to do it in,check the distibutor make sure your pickup is phased with rotor, this will raise combustion temp,whats your ignition set up gmonde

05-16-2008, 03:29 PM	#1
thewrench3 Junior Member Join Date: Nov 2007 Posts: 14 Likes: 0 Liked 0 Times in 0 Posts	Re: need a little help... Well I got the engine all apart today. The cam is ok. The intake valves are tuliped, sucked up into the intake ports. I am going to try to post a pic. Any ideas why? The old valves I had in it never did that. I ran them for two years.

05-16-2008, 04:19 PM	#3
Mark Lewis Member Join Date: Apr 2006 Posts: 345 Likes: 63 Liked 207 Times in 44 Posts	Re: need a little help... too much timing or lean?

05-16-2008, 07:53 PM	#4
BillK Member Join Date: Nov 2005 Location: Waldorf Md Posts: 230 Likes: 12 Liked 30 Times in 17 Posts	Re: need a little help... TW, Something is causing the valves to get extremely hot. It could be anything in the combustion process. I have also seen it in marine engines when water gets into the cylinders through the exhaust but I doubt this would be the case here. Did you change anything during your "freshen up" that could keep the valves from dissipating heat ? Like a much narrower valve seat than you had before ? Anything else change in your combination ? Not enough timing can be just as bad as too much. Vacuum leak ? Just thinking out loud __________________ Bill Koustenis

05-17-2008, 01:13 PM	#5
mtkawboy Member Join Date: May 2003 Location: Billings Mt Posts: 281 Likes: 183 Liked 54 Times in 18 Posts	Re: need a little help... If the valves were sinking in the head wouldnt the lash get tighter not looser?

05-17-2008, 03:24 PM	#6
thewrench3 Junior Member Join Date: Nov 2007 Posts: 14 Likes: 0 Liked 0 Times in 0 Posts	Re: need a little help... Yes the valve lash would go to zero. After, i put new rings, bearing and gaskets thats when the problem occurred. I use a .070 wide valve seat width. But the old valves were the same way. I changed to a thinner head gasket to try and get a llittle more compression. I had always used manley valves in the past. Never had a problem with them. These valves were a no name brand. I am thinking that I am running to lean, the exhaust gas temperature is 1400 deg. in high gear. I run 32 degrees total timing, that seems to be the limit with my combination. It runs slower e.t and mph with more timing.

05-17-2008, 07:47 PM	#8
gmonde Senior Member Join Date: Nov 2007 Posts: 615 Likes: 56 Liked 165 Times in 59 Posts	Re: need a little help... two years ago we had a ford v6 in the shop,same deal intake tuliped also did the exhaust valve in as well ,found that it had a bad crank sensor caused timing to retard and they ran it hot ,check the timing,maybe the bump in compression was enough to do it in,check the distibutor make sure your pickup is phased with rotor, this will raise combustion temp,whats your ignition set up gmonde