Engine experts I have a question.

[AJT]

Although this is not a viper motor, one of my friends had a engine failure in a GT. Can you tell what happened by the picture?

 

[GTS Bruce]

A viper owner pisxed into the intake causing hydrolock,corosion and rusting.

 

[luc]

Rust mean water, hydro lock maybe?

luc 00GTS

 

[ViperTony]

Someone took the heads off and washed the cylinders and forgot to dry? Loose head gasket?

 

[Vic]

Ring lands shouldn't be visible from the top! Looks like the top of the piston got cracked, and that resulted in the cylinder wall getting galled up. Did the head gasket crack, letting water into that one cylinder only? Like Luc + others say, maybe it hydrolocked, breaking the piston top near the ring lands. Thats why there is only rust in that one cylinder?

 

[Tom F&L GoR]

High compression, used MMT (explains the color.) Tiny signs of preignition on the piston, broken ring land, and burning/blow by on the wall. Just a way-out guess.

 

[Vic]

High compression, used MMT (explains the color.) Tiny signs of preignition on the piston, broken ring land, and burning/blow by on the wall. Just a way-out guess.

I'll bite...What's MMT?


too lazy for google..

 

[carguy07]

I'll bite...What's MMT?


too lazy for google..

MMT FACT SHEET

 

[Viper Wizard]

To much boost & a bad tune! Must be a paxton?

 

[Vic]

MMT FACT SHEET

Yikes! Nasty stuff.

Thx for the info!

Tom, MMT causes the color on the cylinder wall? Piston top?

 

[DAMN YANKEE]

And so....what were the specific mods made to this Viper?

 

[KenH]

High compression, used MMT (explains the color.) Tiny signs of preignition on the piston, broken ring land, and burning/blow by on the wall. Just a way-out guess.

Tom, do you have an opinion on MMT? I run Torco Accelerator which contains it. I have done a lot of reading and haven't really seen any real negatives from those that use it other than the orange residue that it leaves on plugs and the like.

 

[VENOMIS]

Detonation caused that by too much ignition timing, too much boost, too high a compression ratio, low grade fuel, or not enough fuel (wrong A/F ratio) and then caused the head gasket to blow as well. It could have been one of those or a combination of all of them. I ve blown up many an engine due to wrong a/f ratios at the drag strip. Dropped cylinders in my supercharged boat due to not having enough water pressure in the block, however if you looked at the piston you would have guessed it was a fuel issue. Been around supercharged engines more than N/A engines and learned alot about what they like and what they dont

 

[DAMN YANKEE]

A J T.....what are we looking at here? What was the build out on this engine? Thanks.

 

[viper spray]

Detonation for sure , did he hear the pinging , that is a GT , right?

 

[AJT]

Thanks for the replies,

I'll have to ask my buddy more specifics, just know it was on a GT.

Andy

 

[Tom F&L GoR]

MMT was developed by Ethyl Additives Co, the originator of tetra-ethyl lead, which was the first, and most effective octane enhancer. Ethyl changed their name several times over the last few years; some parts to Albermarle, others to Afton Chemical.

MMT was supposed to be a safe replacement for lead, but the OEMs worried about long term catalyst efficiency, so they devised a test plan and published technical documentation that killed it in the US. Ethyl similarly conducted tests and published technical documentation showing it didn't make any difference. In the end, the OEMs claim to have found the needle in the haystack and by gosh, it was a really important needle. Ethyl couldn't see the writing on the wall and even challenged the EPA, eventually losing. There continues to be doubt about how the EPA made this decision. MMT was used in Canadian gasoline, apparently without massive death and disease. MMT is, however, a metallic compound and by definition is not allowed in US gasoline.

Technically MMT is as good or better than Pb, but can't be used at high concentrations because of fuel instability, deposit problems, and it doesn't have the "more is better" response that Pb does. Therefore it is usually used along with something else, such as low levels of Pb or highly aromatic gasoline formulations.

The characteristic dark orange color is the giveaway, if that is what happened here.

 

[AJT]

They have not given any detail of mods to the engine. But I think the owner did a pulley swap and lean tune.

" I think the predetonation damaged the ring and allowed oil to be baked onto the side of the
piston wall. According to the info in the thread, I think the head gaskets were still in
good condition when they did the tear down. They think that it is rust on the cylinder wall, but I think with the color that it is caked oil. Just glad it in not my problem."


Thanks Everyone!
Andy

 

[KenH]

Thanks for the info on MMT Tom. The stuff seems to work pretty good from my own limited street tuning experience.

As for this thread, so much for the GT engine being indestructable I guess. First one that I have heard of being damaged even with extra boost on the stock block.