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Discussion Starter · #1 ·
I know this sounds like another one of those "Meth Kit" newbie questions threads, but it's not.

I have been considering putting a meth kit on my TT Auto Supra and talked to a shop about it the other day. He showed me a block from a customer's stock block TT Supra that had a nice big hole blown through the side of it.. The customer had a meth kit on it, dialed in and everything. After driving the car for a while, he came back and had a compression test done. It was fine. The carbon had been cleaned off the rings and elsewhere in his engine, and shortly after that his engine blew up (he was running 18 lbs of boost with the meth kit on). I was told that if you use meth, and it cleans your engine, if your rings are not seated properly or are worn, or some such thing (I forget exactly what he said), that you run the risk of blowing your engine (this is what happened since without the carbon around the rings it somehow caused the engine to blow. I wish I could remember exactly what he said, but it's been a few days. )

What I want to know, is if this is in fact a possibility, and if so, how do you avoid it happening (and why would it happen)? He told me that if you have changed your oil often and taken good care of the engine, you might not have a problem; but, for anyone who didn't buy their car new and doesn't know the exact maintenance history with respect to oil changes, what can you do short of not running he kit (He said it's a crap shoot you take running the meth kit on a non-built motor).
 

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i think it is possible since meth. does not have any lube in it, it makes sense. this is one of the reasons i'm going with a very small shot of alky/water.
 

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That sounds kinda funny about the hole in the side of the block and only running 18psi of boost. Sounds like he threw a rod and it came out the side of the block. I would have to suspect that he did something very wrong to do that kind of damage. I personally have run meth/water for around 1 1/2 or so years and no problems what so ever. I also used to run 24-25psi on 91 pump and meth/water for 18k miles. engine still runs like a champ.

Lawrence
 

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I have not run meth personally but it sounds like with the way he tried to scare you with the blown block etc. and tell you only a built engine could survive that he is trying to sell you a built motor...? Like others said to throw a rod or do that much damage there has to be something serious wrong that is more than carbon deposits coming off...
 

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Cheifbootknocka
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Sounds like possibly a problem with the mixture of meth/water or bad jet mabe ?
 

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Bad Karma Supra
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Dear Lord...get a new mechanic. GN guys have been using this longer than most of us have owned a supra.

1) Almost all methanol you buy has a lube added.
2) The amount you inject vs the amount of gasoline isn't even close.

Breaking a motor that bad (window'd the block) on 18psi - there's something else going on besides a "bad" meth kit.
 

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Discussion Starter · #7 ·
It didn't really make sense to me when he was showing me the block. I've read about many, many, many people having meth injection on their cars and no problems.

No, he wasn't trying to sell me a built up motor. Just his observation. He said he would put the system in, just wanted me to know the potential issues.

That's why I'm asking this question. I want as much feedback as I can get. I am still leaning towards it, but I just want more input.

Thanks for the replys so far. :bigthumb:
 

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Sounds like he is covering his butt on this one. So if there was a possibility of you running out of meth and still continuing to boost 18psi and above and blowing your motor he could tell you "I warned you about this".

Lawrence
 

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teh DJ
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the only danger I could think of is when the controller or pump fails...other than that, it sounds like something else that went wrong....the only way to avoid a meth disaster is to have a fail-safe feature where if the pump fails/no pressure/etc, it automatically shuts off boost...
 

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Honestly I have nothing to add to this discussion and one day I'll look into meth more but from what I've heard from old school racers (40, 50, 60's) they swear meth is no good and they would be very hesitant to use it. I know there are a lot of people using it now so one day hopefully they will explain there precautions about it. As of now I have no need to know so I haven't taken the time to listen to them.
 

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feeding your habit
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water injection is fairly useless at 18psi of boost..... it's only use is to prevent detonation. It won't cause a block to have a problem (unless you hydro lock the top end).
Water injection is largely misunderstood. It's been around for a long long long time and works great. Adding alcohol (fuel) to the water is something that seems supra specific, though an engine is an engine and for the most part unless you are running rediculously low octane (87) and high boost with big big power, you don't need the alcohol. Water alone works great.

-M
 

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meth works good.
Put in a little lubricant (uplon) into the meth, so it doesn't eat away at stuff.
 

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Engine failure from putting a rod through the side of a block did not come from Meth use. It came from catastrophic bearing and/or rod failure. Meth injection has a ton of potential pros like starving off detonation and cooling the pistons and head. The downside of too much meth flow is washing down the oil off cylinder walls and cause premature ring/cylinder wear.
 

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Cheifbootknocka
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98mkiv said:
Adding alcohol (fuel) to the water is something that seems supra specific

-M
I know of lots of mustangs, GN's, Vettes, WRX's and a hotrod that run meth injection with great results.
 

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Adding alcohol is not something that is supra specifc. If your car does not have a strong enough fuel system you run methanol to compensate. If your car has a detonation problem you run more water as water cools better than methanol due to evaporation rate. We run metahnol as well to keep the water from freezing in the winter. You need a minimum of %15 of your mixture to be water in the winter to prevent this from happening. We have been running methanol for years with no problems. There isn't a jet large enough to supply the amount of water to wash the walls in your block.
 

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^^^Agree. Adding meth/alcohol to water is definitely not Supra specific. It has been used since WWII on turbo fighter planes. Just do a google seach and you can read all about it. People swear by different ratios of water to meth, ie 50/50, 70/30 and most GN guys say screw the water and just run 100% meth.

Some people use the meth injection simply as extra fuel since they are running the stock fuel system and it will also give you the benefit of extra octane. However a majority of people also use meth even with their full fuel system. My car now has a full fuel setup and I still use meth, because I don't run race gas in the car 100% of the time. Also, i do not have a fuel delivery issue. Assuming you do not have a fuel delivery issue it seems that the addition of water to the mix def. has some benefits over 100% meth.

I can tell you that I have my meth system set to come on at 8psi, and when it does, my EGT drops by 200F. That is significant.
 

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teh DJ
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alpha6164 said:
I can tell you that I have my meth system set to come on at 8psi, and when it does, my EGT drops by 200F. That is significant.

and your timing should drop too... :bigthumb:
 

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djskyy said:
and your timing should drop too... :bigthumb:

My timing?????
 

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It's up to you and what your car likes but 8psi is a little low for a turn on point. Turning the system on that early will lower the egts too much and you will make less power and have more lag. The more reasonable solution is to turn it on right before full STOCK boost is made or right before whatever boost level your car starts to detonate at to maximize power and mimimize lag.



Is your meth kit controlled by injector pulse or a progressive controller?
 
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