Black1986Beast
No!! It's NOT A Monte!!!
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Hey, I was just wondering what exactly causes blown headgaskets in the case of a TR??
Cuz I'm just curious..thanks
Cuz I'm just curious..thanks
What Causes Blown Headgaskets???
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Ken Cunningham
Post No Bills
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Kinda complicated question. As Buickboy points out, these things cause detonation, too high a cylinder pressure, then blammo! I have also heard that the bolt pattern, number of head bolts, water jacket design, etc. all cause the Buick heads to lift a little under extreme pressure. When they lift, then the cylinder pressure escapes out past the gasket and blows it. Ultimately, it all comes down to detonation.
actually it comes down too.
detonation is caused by a lean condition on the cylinder specially (5,6), buy a power plate and you will safe yourself some headaches, it also cause by overboosting the car but once again your back to leaning the car out when you start to boost..
detonation is caused by a lean condition on the cylinder specially (5,6), buy a power plate and you will safe yourself some headaches, it also cause by overboosting the car but once again your back to leaning the car out when you start to boost..
Black1986Beast
No!! It's NOT A Monte!!!
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So basically, decreasing detonation of any kind will greatly reduce the chance of blowing head gaskets??
And the main way to reduce detonation would be higher octane gas, right?
I heard adding 3 gallons of Xylene to 9 gallons of 93 Octane gas will make the Octane rating around 100..is this true?
Is this a good Idea??
I currently get quite a bit of detonation so I'm looking for ways to reduce it..
I also heard one reason for the high amount of detonation could be a clogged fuel filter, which would cause it to run too lean..Is this also true?
Thanks
And the main way to reduce detonation would be higher octane gas, right?
I heard adding 3 gallons of Xylene to 9 gallons of 93 Octane gas will make the Octane rating around 100..is this true?
Is this a good Idea??
I currently get quite a bit of detonation so I'm looking for ways to reduce it..
I also heard one reason for the high amount of detonation could be a clogged fuel filter, which would cause it to run too lean..Is this also true?
Thanks
Re: actually it comes down too.
That may be just a little bit of a stretch (too lean). In actuality, it's more a function of octane rating of the fuel being burned than it is whether it's "too lean" or not. O2's can be run pretty far down into the lean area and not cause any detonation at all, as long as the octane is there to support it.
Octane is after all the fuel's anti detonation/knock property.
Octane, Boost, and Timing are all major factors in what happens to cylinder pressures at any given point in time, and it's the cylinder pressure that pushes out the head gaskets. Peak cylinder pressures can actually be well controlled even in high boost situations with the right octane. Reduce the octane or raise the boost and timing to the point of detonation and cylinder pressure peaks are HUGE, and WILL damage the gasket.
To what extent depends on the severity and amount of detonation.
Originally posted by wiked87gn
detonation is caused by a lean condition on the cylinder specially (5,6), buy a power plate and you will safe yourself some headaches, it also cause by overboosting the car but once again your back to leaning the car out when you start to boost..
That may be just a little bit of a stretch (too lean). In actuality, it's more a function of octane rating of the fuel being burned than it is whether it's "too lean" or not. O2's can be run pretty far down into the lean area and not cause any detonation at all, as long as the octane is there to support it.
Octane is after all the fuel's anti detonation/knock property.
Octane, Boost, and Timing are all major factors in what happens to cylinder pressures at any given point in time, and it's the cylinder pressure that pushes out the head gaskets. Peak cylinder pressures can actually be well controlled even in high boost situations with the right octane. Reduce the octane or raise the boost and timing to the point of detonation and cylinder pressure peaks are HUGE, and WILL damage the gasket.
To what extent depends on the severity and amount of detonation.
Are you getting audible detonation or knock retard on a gage? What is your boost level and what gear/speed are you in when it happens?
Looking at you signature, things like 60 psi FP regulator and 80 psi fuel pump throw up red flags. It's like somebody told you that's what they are. I trust what people tell me as far as I can throw them. Do you know you have fuel pressure under boost? Have you checked it with a gage? What is the fuel pump (mfg., age and is it hot wired)? What is your fuel pressure set at?
At 18 psi and using a street chip, you shouldn't have audible detonation with 25% Xylene, if everything else is in good working order.
Black1986Beast
No!! It's NOT A Monte!!!
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UNGN
I'm not getting any audible detonation..nothing that I can hear..but I'm getting the retard on the guage..
When I saw the mods done to the car, one of the things said "Eastern Performance Package #1A w/Street Lethal Chip"
Well the chip is 18lbs..and I did some research and emailed ESP, who took over eastern performance's product line and asked them what this performance package consisted of and they replied saying: "2.5'' hooker exhaust, 80psi fuel pump (he said the pump is a walbro/holley because holley took over walbro?? is that right??)
60psi FPR, 160* thermostat and maybe another thing or 2..
I know there's fuel pressure under boost, and there's a rail guage..which I can't read while driving..I don't have a scanmaster, but I plan on getting one..At Idle fuel pressure is around 37psi..I dont know if this helps..and I'm not very sure if the pump is hotwired..what are some signs that I can look for that will tell me if it is??
Also..there's a somewhat loud drone sound coming from the rear of the car when I turn the key forward, but don't start..it's also heard while the car is running and my friend said that it's the fuel pump..any way of getting rid of this sound?
The knock/detonation occurs over 10psi because I remember looking at the guage..then to the sensor and not getting anything..the detonation occured toward the end (not sure what gear I was in, it wasn't a very long stretch of road, didn't pay much attention)
There isn't xylene in the car right now either, I had just put in 93 octane from exxon..
Hope this information helps...
Thanks
I'm not getting any audible detonation..nothing that I can hear..but I'm getting the retard on the guage..
When I saw the mods done to the car, one of the things said "Eastern Performance Package #1A w/Street Lethal Chip"
Well the chip is 18lbs..and I did some research and emailed ESP, who took over eastern performance's product line and asked them what this performance package consisted of and they replied saying: "2.5'' hooker exhaust, 80psi fuel pump (he said the pump is a walbro/holley because holley took over walbro?? is that right??)
60psi FPR, 160* thermostat and maybe another thing or 2..
I know there's fuel pressure under boost, and there's a rail guage..which I can't read while driving..I don't have a scanmaster, but I plan on getting one..At Idle fuel pressure is around 37psi..I dont know if this helps..and I'm not very sure if the pump is hotwired..what are some signs that I can look for that will tell me if it is??
Also..there's a somewhat loud drone sound coming from the rear of the car when I turn the key forward, but don't start..it's also heard while the car is running and my friend said that it's the fuel pump..any way of getting rid of this sound?
The knock/detonation occurs over 10psi because I remember looking at the guage..then to the sensor and not getting anything..the detonation occured toward the end (not sure what gear I was in, it wasn't a very long stretch of road, didn't pay much attention)
There isn't xylene in the car right now either, I had just put in 93 octane from exxon..
Hope this information helps...
Thanks
You may have an external pump. An intank pump whines but its very hard to hear over the engine.
Turn the key to on, but don't start and leave it on. If the pump doesn't shut off after a few seconds, you likely have an external pump. Crawl under the car with the key on and listen for it. An intank pump sounds like its in the tank. An external pump is mounted to the body or frame and sounds like it.
If you have an external pump, there is a high likelyhood you still have a dead, conjoined pump still in the tank. This is why I hate externals so much. The greatest external in the world can't pump any fuel if its still hooked to a dead stocker with a clogged and collapsed sock. This would be one explanation for knock at only 10 psi (not enough fuel)
If the pump is intank, it still may be flaky if its old or its sock is clogged/ collapsed.
Knock at 18 psi with straight pump gas is normal, knock at 10 psi is not.
Turn the key to on, but don't start and leave it on. If the pump doesn't shut off after a few seconds, you likely have an external pump. Crawl under the car with the key on and listen for it. An intank pump sounds like its in the tank. An external pump is mounted to the body or frame and sounds like it.
If you have an external pump, there is a high likelyhood you still have a dead, conjoined pump still in the tank. This is why I hate externals so much. The greatest external in the world can't pump any fuel if its still hooked to a dead stocker with a clogged and collapsed sock. This would be one explanation for knock at only 10 psi (not enough fuel)
If the pump is intank, it still may be flaky if its old or its sock is clogged/ collapsed.
Knock at 18 psi with straight pump gas is normal, knock at 10 psi is not.
Black1986Beast
No!! It's NOT A Monte!!!
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Hmm...well I'll hafta check for that then..so if it's external then I should get a new internal pump?
What can I look for that will tell me if the FP is hotwired??
I didn't get knock at 10PSI, but the sensor was full toward the end of the run and I prolly hit 18psi
What can I look for that will tell me if the FP is hotwired??
I didn't get knock at 10PSI, but the sensor was full toward the end of the run and I prolly hit 18psi
Black1986Beast
No!! It's NOT A Monte!!!
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I just checked it, it sounds internal to me...so now what?
Also, what about the drone sound??
And how do I know if it's hot-wired??
Also, the knock doesn't occur AT 10psi, it occurs passed 10psi because I remember looking at the guage and there was no knock at 10psi...so it had to occur passed it
Also, what about the drone sound??
And how do I know if it's hot-wired??
Also, the knock doesn't occur AT 10psi, it occurs passed 10psi because I remember looking at the guage and there was no knock at 10psi...so it had to occur passed it
SilverSleeper
Senior Member
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- May 24, 2001
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The droning sound is normal for an in-tank pump. It makes noise and reverberates in the tank.
If it is hotwired, it should have a relay located fairly close to the plug for the pump. The relay will have a heavy duty gauge wire running to the front of the car and connceted to a power source (probably back of alternator).
If it is hotwired, it should have a relay located fairly close to the plug for the pump. The relay will have a heavy duty gauge wire running to the front of the car and connceted to a power source (probably back of alternator).
T
turbov6joe
Guest
The detonation causes extreeme cylinder pressures and much abuse to rotating parts. The extreeme cylinder pressures actually lift the heads off the block and eat away, if you will, at the gaskets, thus causing it to blow out. This is why some of us use headstuds, as then tend to offer a better clamping force. Along with that, this is why some folks also use a stage block that offers double the headbolts to hold the heads down, thus allowing greater cylinder pressures without headgasket damage.
what if you have knocked a bunch of times over the years but never blown a gasket? does this mean that the gasket is still good? like nothing ever happened? or will knocking OVER TIME eat away at the headgaskets or something and someday you boost to 10 lbs and BAM...???
BlackBeauty
Member
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My fuel pump doesn't drone, it whines in the tank. It's a Walbro 307, and it can easily be heard if my car is on and I walk to the rear quarters on the car. To check for a hot-wire kit, look at the back of the alternator, and there will be a screw there, with wires hooked up to it. Follow each wire till you find out where they end. You want to find one that ends at the fuel tank. My hot-wire kit goes from the back of the alt., then to the driver's side front quarter panel, where there is a fuse, and we placed it next to the other fuses and relays right there, then it goes under the car along the brake lines, it always stays on the driver's side of the car. Good luck.
Black1986Beast
No!! It's NOT A Monte!!!
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Well I guess you could say that my fuel pump whines too, npt drone..but it's easily heard while the car is on..is the sound supposted to go away or can it be made to go away??
Also..I remember checking under the rear of the car and seeing some type of fuse connection near the gas tank, so maybe this is it..I'll check tomorrow
Thanks
Also..I remember checking under the rear of the car and seeing some type of fuse connection near the gas tank, so maybe this is it..I'll check tomorrow
Thanks
F
Fred 86 GN
Guest
Run your gas tank low on fuel and "get on it" -- the extreme lean condition that follows will blow a head gasket -- ask me, I know 
Make sure to have plenty of fuel for the pump to suck up when launching the car!
Make sure to have plenty of fuel for the pump to suck up when launching the car!
Blown Headgasket
I blew mine a few years ago. I was having big time knock and couldn't find out why. Tried a few things then let it rip then BANG
It was still running and making a popping noise. Turns out the #1 blew into the intake and not losing any fluid at all. Lucky I guess 
After it was torn down I took off the EGR valve and did a vacuum test on it and it was leaking. The diaphram was ripped. The sharp metal had cut the rubber but that ment the rubber would have to inflate like a balloon. How could this happen 
The ckeck valve in the vacuum line going to the EGR valve was not working hence causing boost pressure to inflate the EGR diaphram and cutting the rubber. 
Replaced the gasket, EGR and $.94 check valve and things were fine after that.
Just my .02
I blew mine a few years ago. I was having big time knock and couldn't find out why. Tried a few things then let it rip then BANG
It was still running and making a popping noise. Turns out the #1 blew into the intake and not losing any fluid at all. Lucky I guess After it was torn down I took off the EGR valve and did a vacuum test on it and it was leaking. The diaphram was ripped. The sharp metal had cut the rubber but that ment the rubber would have to inflate like a balloon. How could this happen The ckeck valve in the vacuum line going to the EGR valve was not working hence causing boost pressure to inflate the EGR diaphram and cutting the rubber. Replaced the gasket, EGR and $.94 check valve and things were fine after that.Just my .02
