What is the reason for meth with headers?

Is it to get the most power out of the setup or to keep it safe?

Running at about 8lbs with the ECS restrictor plate. I signed up for that 1/2 mile event but have to run street tires. I get good traction now and planned on headers/meth over the winter.

I'm thinking of putting the headers on now and having it tuned for a nice bump in HP.

I'll drive it some more and see how I like it around 620rwhp or so, about 70 over where I am, then decide if I want to go beyond that.

Is that still a safe number without meth?

The consensus seems to be, without price being an issue, the ARH is the best header all around for the C7, is that true?

With regards to the headers and noise level. I'd like it in Touring to be as quiet as it is now with NPP, in Sport/Track not as interested. How much of a noise difference do the CATS make?

If you did not do cats would you do someone else's X-Pipe or buy it as a system?

One thing I do not want is the smell either, I had a catless C5 with cam/heads/headers and you spelled like a gas station.

 

As far as I know, there is no advantage to using Meth when the only other mod is headers.

Typically Meth is used in Supercharged applications for safety if running more than 7 lbs of boost. I run 10 so the Meth is needed for safety reasons as detonation will kill your engine if just running straight 93 octane fuel. If you have access to unleaded racing fuel and that's all you ever run, Meth may not be needed.

As far as noise, forget it. Even in touring mode, the exhaust is fairly loud once you get above 2500 RPM. If you want quiet, avoid LT's. I have them and love them but I enjoy the additional exhaust volume.

I'm running a catted X-Pipe with my LT's.

I personally would want Meth with the 8lb restrictor plate.

 

Thanks for the comments on the noise but must have missed this part of my post:

"Running at about 8lbs with the ECS restrictor plate. I signed up for that 1/2 mile event but have to run street tires. I get good traction now and planned on headers/meth over the winter."

 

Yes, missed that. I would want Meth with the 8lb plate. Hate to see you grenade your motor. Others may disagree

 

Let's not forget to mention most of us can only get 91 octane. At 8psi and 91 oct, I'd definitely run meth. Another matter to consider is not about the amount of boost... You need to consider the LT1 stock fuel supply starts to run low on supply over 600-650rwhp. If I were you, I'd upgrade the pump to the lt4 and add a cam with a bigger pump lobe or save yourself the trouble and get meth.
You can also get a couple extra points octane with Torco.

I agree with headers increase sound. WOT sounds like hell is breaking loose. However, cats do help a lot so if you don't like the smell and the sound, get cats.

 

I'm running 700 to the wheels using the stock LT1 fuel pump and no lash cap. No fuel issues since the install.

 

yea, but doing at least the lash cap is good insurance. That's what I'm doing.

 

At first I did have cats but after more investigation I found that cats +100% Meth can equal a grenade for the engine, at which point I had my cats gutted.

My big concern was just as yours; smelling like I fell asleep behind a car. I now have no cats (gutted them) on mine (ARH LT) and don't have a bad smell at all, this can be somewhat tuned out. I'm not saying 100% BUT at least 80%. Put it this way I can drive with the windows down or top off, sit at a light and not smell like I was part of a pit crew at an NHRA event.

As far as sound when I put my package together that was a major concern. It had to make the wife happy and it is my daily driver. I used to have an 06 GTO that was definitely pure race-car ( A4 low 10s 600+ to the wheels all motor 418ci). You smelled like it and heard it coming before you saw her. Now in my line of work it wasn't too professional smelling like you left a gas station or turning on every car alarm you drove by in the parking garage (though it was pretty fun). So I have ECS/ARH LT/Alky/non NPP exhaust and you cant tell anything until I am WOT, even the BOV is pointed in the fender so you don't get the dramatic sound (unless your WOT). You get a slight rumble from the LTs but it sounds like you just modified your exhaust. But at WOT is another story. On a side note its not loud inside the car its more-so outside the car where you hear it.

 

Headers do not make or break meth, what makes the necessity for meth is the lack of octane in pump gas and lack of fuel supply from the vehicle.

620 RWHP is right at the limit of what the car can supply, and is past the limit of what pump gas octane can safely support.

Meth also keeps the IAT's lower so you will not be effected as much during a long run out like a mile event, or in the summer months.

It also cleans the inside of the intake, valves and piston tops incredibly well. A 100k engine when torn apart will just have a brown film on the pistons, a non meth car will have carbon build up throughout. Especially on a DI engine.

IMHO, I would never own a SC car without meth. I want the best bang for my buck, and I want as much power as possible. The SC can add 100-125 rwhp on pump gas. Add meth for only a little more $$ and you can add 200-250 RWHP.

I also would feel more confident in a 700 RWHP C7 with meth, then a 600-620 RWHP C7 without.

I hope that helps your decision.

 

Good to know on the last statement here.

 

Thanks, that explained it exactly the way that I want.

I'll give you guys a call in a few to order the meth kit.

 

How does cats and meth equal a grenaded motor?

 

Meth Eventually destroys cats and unlike the old school cats these if they seal up will cause a serious issue.

 

This is a great explanation, Doug. It helps me feel at ease that the Alky kit I am installing with my blower really is the best choice. Thank you

 

Another question.

With Meth, good tuning, etc @ around 650rwhp would you still do the high octane gas?

Sponsor said no gas on site and I'd have to source some and have it sent there ahead of time.

 

unless you are going to have HP tuners & be able to go from one to the other at moment notice. Only tune it with all being the same in the car at all times. PUT IT THIS WAY TUNE WITH WHAT GAS YOU HAVE TO DRIVE WITH ALL THE TIME.