DaSilva tune blew my head gasket

trinity_gt said:
Please. Headgaskets are simply not common failures due to detonation on normally aspirated engines. They just aren't. I'm not saying it can't happen, but it's not common at all. Even in supercharged apps headgaskets do not usually blow before ring lands break or pistons otherwise break when detonation sets in. When they do go it's usually because of assembly deficiencies or in extreme cases because of the head actually lifting off the block due to extreme cylinder pressure and insufficient clamping.

"And speaking of "misinformed"... A blown head gasket is a "fuse"? Who's misinformed? Get a clue dude. Sparkplugs and their electrodes are the canary in the coalmine when it comes to detonation: they will melt away or the porcelain will show bits of aluminum from the piston long before the 30-thou or so thick stainless steel fire ring on a head gasket goes away. An owner hearing persistent, severe detonation should be pulling plugs and checking their health before merrily proceeding to knock parts out of their engine.

It's a headswapped car and it has blown a headgasket. My first suspicion would be the swap.

I want to hear from Try Me: What do the plugs look like?



:rolleyes: Blowing a headgasket is always a bad thing. Ever see what glycol does to bearings after coolant leaks into the oil drainbacks?



It's a headswapped, PI-cammed normally aspirated modular with a few bolt-ons. Why are you even bringing dynamic compression ratio into this? BTW, why didn't your link mention the inertia of the intake charge when considering the DCR?

:rolleyes: :rolleyes:


I've addressed the possibility of faulty install.
I checked the oil and no sign of glycol.. no sign of oil in the resevoir.

It's blowing out between the head and deck, passenger side forward towards the valley. Minute bubbles at high idle.. like when you spray soap water on a punctured tire. Drive a bit.. low coolant light comes on.. fill.. drive.. light comes on again.. car continues to stink like burnt coolant from it collecting below the intake.

I'll pull the plugs tomorrow and update (i got some errands to run for my boat so if not tomorrow then the day after).

For now the car is going into storage - i'll deal with it next year.. and UPS the bad gasket to DaSilva with thanks.

Reading some of the critisism here and from other boards i've posted on is just a sample of what i'd face if i took my case directly to DaSilva. You've all been through it - not matter what the facts point to, it's always the customers fault.

Don't piss on me and tell me it's raining.
 
sgarlic said:
Make up your mind. You made a mistake, so own up to it like a man.

I said I've never heard of it happening on a normally aspirated car. Anything is possible but a blown headgasket on a normally aspirated car due to detonation is rare. These statements are in no way contradictory. I have never heard of it and it's not common at all.

Try Me, I'm not trying to piss in your cornflakes: headgasket failure on a normally aspirated engine running a known combo (i.e. NPI headswapped with PI components and a few other bolt-ons) is not an everyday occurence if the thing was assembled correctly, even in the presence of detonation. Other parts are more likely to fail first; brittle hypereutectic pistons, for example, are likely to suffer damage before a stainless steel fire ring in a headgasket opens up. The sparkplug porcelain is more likely to crack or shatter in hard detonation. If the detonation was so absolutely horrendous and you spent 5 hours driving from Toronto to Ottawa with the thing rattling all the way, and ended up there with coolant bubbling out then it's possible the whole engine is done. If the detonation was so very bad that it blew through the head gasket then it's likely things like piston ring lands are also hurt.

BTW, how would detonation cause a headgasket failure such that "coolant and air bubbles {are} seeping from the passenger side head"? I could see a detonation-related gasket failure (i.e. fire ring surrounding a chamber burned through) as allowing compression and combustion pressures into the coolant or coolant into the combustion chamber but why would it leak "outward", seeping out between the junction of the block & head? Did it severely overheat on the way?
 
My first guess would be the install because blowing head gaskets on the SOHC engine is a rare event. These cars are known to not cause head gasket failures.

Now how experienced is the tuner? Where is the dyno sheet so we can see the air/fuel curve? Do you know how much timing he has your engine advanced?
 
What has been your contact with DaSilva, since this happened? What is their side? Did they say they will look at it?
These are some things should also be included.
You haven't even pulled the plugs? If so, what do they look like?
You drove the car 5 hours and it was detonating that bad?
Something really doesn't sound right.
You are not even open to the posibility that this might have happened without the tune?
It may have had everything to do with Dasilva or not. Fact is, no way I drive 5 hours after a tune with a car running like *****.
:shrug:
 
Head gasket failures with these cars is usually caused by repeated overheating, or improper sealing of the gasket.

You might get with Silva and see what you guys can come up with as far as a solution.
 
trinity_gt said:
Please. Headgaskets are simply not common failures due to detonation on normally aspirated engines. They just aren't. I'm not saying it can't happen, but it's not common at all. Even in supercharged apps headgaskets do not usually blow before ring lands break or pistons otherwise break when detonation sets in. When they do go it's usually because of assembly deficiencies or in extreme cases because of the head actually lifting off the block due to extreme cylinder pressure and insufficient clamping.

"And speaking of "misinformed"... A blown head gasket is a "fuse"? Who's misinformed? Get a clue dude. Sparkplugs and their electrodes are the canary in the coalmine when it comes to detonation: they will melt away or the porcelain will show bits of aluminum from the piston long before the 30-thou or so thick stainless steel fire ring on a head gasket goes away. An owner hearing persistent, severe detonation should be pulling plugs and checking their health before merrily proceeding to knock parts out of their engine.

It's a headswapped car and it has blown a headgasket. My first suspicion would be the swap.

I want to hear from Try Me: What do the plugs look like?



:rolleyes: Blowing a headgasket is always a bad thing. Ever see what glycol does to bearings after coolant leaks into the oil drainbacks?



It's a headswapped, PI-cammed normally aspirated modular with a few bolt-ons. Why are you even bringing dynamic compression ratio into this? BTW, why didn't your link mention the inertia of the intake charge when considering the DCR?

:rolleyes: :rolleyes:

Compression ratio comes into the equation because a PI swap on a NPI car raises the compression ratio due to the smaller dish on the NPI pistons (11cc vs. 17cc)...but I'm sure you already knew that... :rolleyes:

As for blowing the headgasket being bad...well, I'll take that versus bent connecting rods ANYTIME! Apparantly you've never owned a car with that type of investment...

As for the "fuse", headgaskets are very much like that in that they will often times blow before severe damage is inflicted. Not always, but it certainly does happen. If you've never seen this happen, you simply haven't spent enough time racing. I NEVER said that blowing a gasket was the way to check for detonation, or to NOT check the plugs, so I'm not sure why you would criticize my post.

BTW, I didn't write the link, and was intended for beginners to give a basic overview of what DCR is. I think it does just that...
 
forpit2000gt said:
What has been your contact with DaSilva, since this happened? What is their side? Did they say they will look at it?
These are some things should also be included.
You haven't even pulled the plugs? If so, what do they look like?
You drove the car 5 hours and it was detonating that bad?
Something really doesn't sound right.
You are not even open to the posibility that this might have happened without the tune?
It may have had everything to do with Dasilva or not. Fact is, no way I drive 5 hours after a tune with a car running like *****.
:shrug:


All your questions except the plug conditions are answered in my original post and in the reply's following... you summary of events is innacurate.