I talked to a guy (who came recommended by friends) about tuning my car next week to make sure it is all good. i just bought the car.

Told him my set up (LS3, Vortech V-3, Cam, Headers, Methanol) he asked what boost was at when it was tuned last (by the previous owner). I told him the dyno sheet says 9.7 lbs. He said that meth is not needed below 10lbs boost?

Does he know what he is talking about?

 

Wrong. Lol its always beneficial. Your in new york I see, and it can get hot there as well so the meth will definetly keep the IATs cooler allowing you to add more timing and gain more power on the same boost all the while running a much safer tune than you would be if you wanted the same kind of power without methanol.

 

Needed is different than recommended or helpful.

Is it needed, no. Is it good, yes.

 

The tuners statement is incorrect to begin with though, as meth isnt "needed" for high boost applications either... (like maybe 10psi+)

it is never "needed" but always beneficial in forced induction applications.

 

The tuner is very correct and as a matter of fact it is never recommended but if a owner wants it because other tuner/owners said its important then as a tuner he can tune the car for it, but I don't want it in my car and is making as much power as anyone and everyone as the case may be with my equivalent.
Methanol causes corrosion very fast and when used it is recommended to drain overnight throughout the system to avoid corrosion, now the question is would anyone drain their system after every use it?
(I know some might remember from the RC days with their RC toys)
Most tuners use methanol for safety of their bad tune but a real good tuner don't have to use methanol for safety, I have tried one of those fake tuner who brags here and is always here to answer everyone question, he tuned my car and it blew up within days.
My friend last tuned my car took the methanol out and retuned the car and it made the same power with the fake tuner and is running stronger than that fake tuner tune.
When a tuner uses methanol the IAT reads lower because he is spraying the methanol in front of the Air Temperature Sensor, which will read low and will accommodate more timing which makes more power for a while till the day that will come and just one simple malfunction with the meth and a motor is needed.
Now I am opening a can of worms that will hurt a lot of tuners who depend on methanol, but OP its now up to you to decide whether you trust your tuner (I trust my passed tuner and my present tuner who both don't believe in methanol and is very great with their job) and believe in him and willing to take his advice and not everyone else advice.

 

If you want all the power your rig is capable of making, you need it. If you don't mind sacrificing hp for simplicity, maybe not. Kind of your call.

 

Without meth you will notice a drop in power as you go WOT a couple of times (higher IATs). Meth will keep your IAT in check and keep your power level up. It is worth it IMO...plus you will probably want to pulley down later for more boost anyway...boost is addictive! Higher octane helps too.

 

Shoot. I run E85 and meth. Even on E85 my IAT was 200F on a 115F day. Now with meth I'm at 60-70F IAT. Which allows four more degrees of timing. In my case that was almost 50rwhp.

 

my car came with the meth already installed and it was tuned for it already so I will leave it in.

I just bought the car last week so I am just getting the tune checked out so I am comfortable knowing it is safe and I can go spank some friends of mine with gt500s

 

E85 won't do anything for temps until after the injectors and then its a short distance to the combustion chamber.

 

The question being asked is: "Is methanol injection needed below 10lbs boost".
The answer is "NO". Anyone who says otherwise doesn't know what they are talking about. Yes it is beneficial but you didn't ask that, you asked if it was needed. I personally ran for 30K miles without it and now that I run meth I miss the hassle-free simplicity of just filling up and going for a road trip without having to worry about where I can find it along the way.

That said if you already have it, there is little reason to get rid of it. If he is not comfortable with your particular setup, find someone who is.

 

As long as your IAT sensor is behind where you are injecting the meth, you can adjust the tune to pull timing if the meth stops. The IAT's will go up and the tune can be done in such a way as to pull enough timing to keep your motor from grenading. This is easier to do at low to medium boost. Guys running pump gas and 14psi plus might not be able to get timing out quick enough to prevent a big boom.

If your IAT isn't behind the nozzle you can get a breakout harness from Caspers and use a 4th gen F-body sensor. I actually drilled my manifold just behind the throttlebody. Works great there.

 

I considered looking at your car before I bought this but I could not own 3 black cars in a row !!! I needed a change. Nice ride !

 

 

Just because "your" tuners didnt recommend it, doesnt mean its "never recommended" like your saying. Couldnt be farther than the truth actually, as you yourself said some tuners "depend on it" ( which is also misleading. They arent addictied to meth like some methheads on drugs, but as tuners they offer it as a way to generally increase efficiency). That being said...

I will agree with you anything can happen and the meth could stop, but any tuner worth giving your money to will compensate like it was stated above. The same thing could happen running a heavy tune on no meth.

Bottoms line if your going to modify your engine, you need to know going in that you could break something...lol

But ill also agree with you that you need to trust your tuner. Thats what you did. Thats what I did, and thats what the OP should do. If he doesnt, get another tuner OP. Although id say if its already installed there is no point in removing it unless your absoloutly adamant that you dont want it.

 

I know this will open a can of worms but I have wondered for so long about this whole issue.
Here's my thinking, although I really have no proof, and don't know how to test it.
On a PD blower like mine, I inject meth into the intake. The IAT sensor is in the back of the blower after the rotors. It is measuring the air temp just before the air enters the cylinder. I see IATS drop some, maybe 20 degrees, but nothing like a centri.
Now...... realistically, is your intake air into the cylinders really dropping from 200 to 70 degrees. I have a very hard time believing that. Is it not possible that because you centri guys spray the meth directly onto the sensor, that it doesn't accurately reflect the actual temp of air going into the cylinders ? Wouldn't it be like putting cool water on a thermostat. It would read low, but the air around it would still the same temp as it was before.
Like I said, I don't really know, as I cant measure the air temps entering a cylinder, but I have been wondering about this for a while, and figure this might be a good place to bring it up.
Any thoughts on this ?

 

I recently added meth to my A&A and blower cam car. It was dyno'ed at 669 RWHP before the meth and after meth it dyno'ed 648 RWHP. This just doesn't seem right. I did get a new McCleod RXT and aluminum flywheel installed in place of the stock clutch.

Could the clutch cause a loss in power? Is the meth not working properly?

 

Did you retune the car??? Or just add meth and dyno?

 

Retuned. Same tuner and same dyno. It was quiet a bit cooler the first time that it was tuned. Surely weather couldn't make that much difference. Oh, and the boost went from 9.7 on the first tune to 9 this time. Is this normal variation or is something not right?

 

Cooler weather will show more boost. That's why you lost .7psi most likely. What AFR is your tuner targeting on the meth? Should be around 10.5-10.8 with a single nozzle kit. Was your old tune pulling timing for air temps? What was the old commanded timing versus new tune? What was actual timing of old tune versus new?