951, the devil in disguise
02-13-2003 | 10:00 PM
#1
Thread Starter
Three Wheelin'
Joined: Feb 2003
Posts: 1,666
Likes: 2
951, the devil in disguise
What is it about these cars. No sooner you think about something going wrong or talk about it, it does. I mentioned last week about my need to upgrade the Headgasket and wham the dreaded Headgasket failure strikes again. No high boost, AFR good, just a failure of the Gasket where its unsupported between the fire rings. Only good news is I made it home before it happened. Was away on business. Does anyone used RedLine water wetter? Does this help Gasket from coming apart? I'm wondering if its the water/coolant I'm using.
Ok so where's this new Headgasket?
Ok so where's this new Headgasket?
02-13-2003 | 11:29 PM
#4
Burning Brakes
Joined: Nov 2001
Posts: 1,084
Likes: 0
From: San Diego
Hold on there pardner,
If your head gasket blows, its for a reason....detonation, caused by more air than fuel, or fuel that burns to quick. If detonation can eat thru a steel ringed head gasket (like our stock headgaskets), then it can eat thru your aluminum pistons just as easily..the headgasket is a safety valve of sorts..sure, if its tuned right, it should never go, but in the event of something going terribly wrong...I would rather the head gasket go, than prolonged detonation eating a hole in the piston.
A solid steel headgasket sounds good on the surface, but it could cause real damage to your block or pistons.
I ran 22psi on pump gas for years, without ever blowing a gasket...infact, to this date....on any customer or personal car...stock headgasket or widefire...I have never blown one, this includes racing and street. Just keep it tuned :-)
Take Care!
If your head gasket blows, its for a reason....detonation, caused by more air than fuel, or fuel that burns to quick. If detonation can eat thru a steel ringed head gasket (like our stock headgaskets), then it can eat thru your aluminum pistons just as easily..the headgasket is a safety valve of sorts..sure, if its tuned right, it should never go, but in the event of something going terribly wrong...I would rather the head gasket go, than prolonged detonation eating a hole in the piston.
A solid steel headgasket sounds good on the surface, but it could cause real damage to your block or pistons.
I ran 22psi on pump gas for years, without ever blowing a gasket...infact, to this date....on any customer or personal car...stock headgasket or widefire...I have never blown one, this includes racing and street. Just keep it tuned :-)
Take Care!
02-13-2003 | 11:43 PM
#5
Thread Starter
Three Wheelin'
Joined: Feb 2003
Posts: 1,666
Likes: 2
Actually, the fire rings are intact but have moved. The gasket failed between the cylinders. It looks like the material just got eat'en away. that is why I wonder if its from some coolant/gasket incompatability. I too have had great success with the stock gasket, never had a sealing problem, until last 2 gaskets. Both are from same apparent fault. I'm no engine guy, but I see what I see and my Gasket plain and simplely gave up between the cylinders. I'm sure another type of gasket material may help with this problem. I would like to hear from others and particulary engine builders who can offer reasons for this.
02-14-2003 | 12:31 AM
#6
Burning Brakes
Joined: Nov 2001
Posts: 1,084
Likes: 0
From: San Diego
Is your head lifting? How many gasket replacements have you done on the same studs? When you say the material has been eroded away, are you refering to the metal or the paper/steel/fiber body of the gasket? In any case, if the fire ring has infact not been burnt thru (and coolant will not eat thru it), then I would look at the studs stretching under boost. I have done many jobs on cars that have had the stock gasket inplace sooo long that only the fire exists, and the fiber was all but gone, and still no leaks. I have also seen oblonged gaskets that have given due to stud stretch.
Post away :-)
Take Care!
Post away :-)
Take Care!
02-14-2003 | 03:46 AM
#7
Race Director
Joined: Jul 2001
Posts: 14,075
Likes: 3
From: Santa Barbara, CA
"I just read about a new headgasket made of some 'springy steal' that never blows up. I forgot where maybe it was on dannos site or something"
Yup, the composite spring-steel construction of our <a href="http://forums.gururacing.net/viewtopic.php?t=43" target="_blank">ultimate headgasket</a> actually allows the headgasket to be re-used several times. Production is in its final stages and these will be available in a couple weeks.
"Actually, the fire rings are intact but have moved. The gasket failed between the cylinders. It looks like the material just got eat'en away. that is why I wonder if its from some coolant/gasket incompatability."
Hmmm, sounds like inadequate clamping or a warped head/block interface? One problem with the stock and aftermarket studs are that they have straight sides. In order to develop tension, you have to tighten them up to just under their yield strength. This puts a lot of load on the 1st couple of threads on either end. After loosening & tightening them a couple of times, you may actually stress them over their yield limit, at which point, there's zero tension clamping the head down due to plastic deformation of the material.
We're offering a new type of head-stud never before seen in the 944/951 market. A super high-strength 190k-psi stainless stud that's homogeneous all the way through (not just coated with a hard black stuff like others on the market).
In addition, the sides are waisted to allow tension-stretch well before the yield limit. This gives the stud a lot of overhead before taking a permanent stretch and relaxing the clamping pressure on the headgasket. The metric nuts are 180k-psi chromoly with metric threads...
These should also be ready in a couple weeks. We'll be providing a complete bundled package with the headgasket and studs.
BTW, find out WHY your headgasket blew in the first place. Simply slapping on a stronger headgasket is not the solution because it will move your failure point to the next weakest part in the engine, like your valves or pistons... <img border="0" title="" alt="[Frown]" src="frown.gif" />
Yup, the composite spring-steel construction of our <a href="http://forums.gururacing.net/viewtopic.php?t=43" target="_blank">ultimate headgasket</a> actually allows the headgasket to be re-used several times. Production is in its final stages and these will be available in a couple weeks.
"Actually, the fire rings are intact but have moved. The gasket failed between the cylinders. It looks like the material just got eat'en away. that is why I wonder if its from some coolant/gasket incompatability."
Hmmm, sounds like inadequate clamping or a warped head/block interface? One problem with the stock and aftermarket studs are that they have straight sides. In order to develop tension, you have to tighten them up to just under their yield strength. This puts a lot of load on the 1st couple of threads on either end. After loosening & tightening them a couple of times, you may actually stress them over their yield limit, at which point, there's zero tension clamping the head down due to plastic deformation of the material.
We're offering a new type of head-stud never before seen in the 944/951 market. A super high-strength 190k-psi stainless stud that's homogeneous all the way through (not just coated with a hard black stuff like others on the market).
In addition, the sides are waisted to allow tension-stretch well before the yield limit. This gives the stud a lot of overhead before taking a permanent stretch and relaxing the clamping pressure on the headgasket. The metric nuts are 180k-psi chromoly with metric threads...
These should also be ready in a couple weeks. We'll be providing a complete bundled package with the headgasket and studs.
BTW, find out WHY your headgasket blew in the first place. Simply slapping on a stronger headgasket is not the solution because it will move your failure point to the next weakest part in the engine, like your valves or pistons... <img border="0" title="" alt="[Frown]" src="frown.gif" />