For those of you in the 8+ Psi range, I'm curious if there's a way to get higher boost without needing water/meth/alky injection to cool the air charge.

I'm curious because it seems the injection system is something that would require a lot more room, more maintenance and would need to be refilled a lot.

 

Pay to play

 

If you're looking for low maintenance then maybe you should go NA.

 

It will cost a thousand or less to install meth. If you're not going that high with boost you don't need it.

 

But the added insurance and hp is not a bad thing to have either. My car is running the snowperformance unit and it works just fine.

 

I've had the same question. A few years ago, I ran a Vortech blown (T-Trim) 383 LT1 Camaro at 16 psi without meth, but now my tuner is pushing me to add the alky if I plan on going to 12 pounds on my Procharged (F1C) 427 C5.

 

The concern of running or not running meth isn't simply the added octane and lower IAT's you get with the meth, but also the higher cylinder temps that you will get without it. Over time, that heat can slowly do damage. It is a fact that a properly tuned car with meth vs without, that the one with will last longer.

 

High cylinder temperatures can scorch a piston, weaken rings, and tulip valves. Or worse. If you have a good tune and fuel and are running low boost you probably don't need meth. That's assuming you have the right pistons, rings and valves. Stock motors should probably run meth even with lower boost pressures. JMO.

 

Mine uses the windshield tank, and pump in fender...so, not alot more room. As for refilling, that depends on how often in the boost. Figure about 4-5 gas refills before a meth refill (mileage of course varies). Maintenance, not sure what's more about it, only had the system since August.

To me, it's worth it.

 

You could drop the compression, then you won't need meth. You could also run race gas or E85. For me, the meth was the most convenient solution and it works mahvelous.

Wow mine needs a refill on every tank of gas. Guess I can't keep my foot out of it, hehe.

 

meth is around 3 $ a gallon. i bought a 5 gallon jug when i first finished my car and still have half left. you dont use it that much.

 

13 lbs here without meth, but looking to add it soon. Especially after what I read here

 

I'm running meth on my n/a aspirated 402 stroker. Of course, I also have a big shot of nitrous to. It only sprays during wot.

 

A meth pump is only the size of a soda can. I use windshield washer fluid and I only have to fill it up every 2-3 tanks of gas

 

Hope this helps.

Every PSI of boost is about 11 degree's. At 10 PSI boost your at 110 above ambient. So its 100 DF outside.. 10 PSI.. thats 210 degree's coming from the blower. When you compress air it heats up.

That 210 goes through an IC to bring it down.. how far down depends on the IC, how efficient it is, how much air gets through the core, etc. The larger the core, typucally the better temp control it has. The higher the RWHP.. the more air it has to cool.. the larger the IC. This is why if you look at race cars that make 1000+ HP they'll run liquid IC inside the passenger compartment. The temperature going into the motor needs to be less than 150. Once it goes up.. your asking for a heart attack. Most tuners will show that temps below 140 gains are minimal.

So the fights you have with a blower are temperature, cylinder pressure, and detonation. Temp is IC. Cylinder pressure=boost, detonation is when you run higher boost, hotter temp, and induce spark knock. You can pull timing and run lower octane on higher boost.. but lower timing brings up EGT's and cooks the cylinder.

Solution.. Run a properly matched IC to support the HP airflow.. and.. run good gas to support higher timing.. this keeps the egt's down and slows the burn so it doesnt detonate. The downside is a large IC blocks the radiator and now it runs hotter.. and the expense of good gas/filling up is the other. This is why the meth systems are popular. But the trade off.. is now there is one more thing to watch/fillup. No free lunch.

OR.. drop some coin.. build a bigger CI motor.. improve its airflow(Bigger cam, larger blower, etc).. now you can make more power with less boost. And this can run crappier gasoline. Until you get the itch for more.. and back to square one

Ex a 346 at 20 PSI or a 427 at 10 PSI. They both can get you the numbers.. or a 572 at 6 PSI The larger the motor.. the less octane it needs to get to a given HP. Probably take 40 PSI with a 4 cyl motor to make what a 346 does at 20. Thing is the higher boost apps.. wont be pump gas friendly.

You can run 16 lbs of boost on straight pump gas.. if the compression is lower, timing is lower, and temps going into the motor are moderate. Knock sensor on these motors doesnt lie.

 

You dont state what your current intake temps are. You dont state CR. You dont state type of forced induction.

If you build your system correctly, then you absolutely do not need water/meth.
yes in some cases you using it can see benefits. But it certainly isnt essential.

I can quite safely run 20psi without any water/meth, or I can push harder with water/meth.

Use a sensible CR, have a proper intercooler then you do not need any form of additional liquid cooling.

 

Why not 22 PSI or 24 PSI? Even 26 PSI.. what stops you from increasing?

What do you consider safe EGT, timing, and air fuel? On that note.. what do you consider safe intake air temp? safe octane number?

I agree its about combination.. problem with a Vette and its nose is getting air through an IC. And proper sizing of that IC.

 

i have the water/meth injection on my 02 magnacharged runnin 8lbs boost; stock motor and bout to go to dual nozzels ; have it set up to spray on boost or at idle with the fans running for example with the a/c on fans turn on and the meth starts spraying; its soo effective after driving the car for 45 mins "very spiritedly" very very .... tires are bald bald bald, i let the car run for 5 mins at idle in neutral w/ ebrake on and after i shut the car off i can lay my hand on the magnacharger and cant feel barely any heat at all ; definetly never have to move my hand from the heat; works great not to mention its like running 120 octane or so .. nice boost and cooler, cant wait to halo spray the intercooler to see just how cold it can get

 

Not sure what you are getting at ?

I stated I am running 20psi quite safely. So why are you bringing 22, or 24 into it ?
Although on various other non-LS engines yes I have used in excess of 26psi boost on many turbocharged engines with no problems.
Ive never sought the level of power that might yield on an LS though

But yes there is absolutely no reason if the CR is chosen with higher boost in mind, then of course you could run higher boost quite safely.
I would try most boost in my own car, but with a supercharger that isnt as simple as playing with boost control.

As for safe EGT, timing, AFR etc again, you know as well as anyone that is a very generic question, and there is no generic answer.
Safe is not blowing up and performing as well as it can.

And safe intake temp ? Again, safe is such that when your engine is tuned, it doesnt blow up. But I would be concerned at anything over say 40-50degC ( 100-120degF )
But with proper intercooling, you shouldnt really be seeing temperatures at that level.
If you dont have room for a proper IC, then you need to build your setup with that in mind, and if need be lower the CR.

And again, safe octane ? silly question. Ive only ever used straight pump fuel, so I dont know what you might call safe. For me that is 97RON, which is about the equivalent of US ( 92/3 PON )
It's the best fuel available to me, so it's all I'll ever be using.

 

Most applications I have seen on the gasoline(ethanol mixed) we have here in the states dont reach that kind of boost safely. So I was just asking to see what you where doing as far as compression, timing, air fuel, etc to achieve your safe state of tune.

I dont know if you do your own tuning or someone did it for you.

Typically most tuners I know go off the knock sensor.. if it knocks.. it needs to be backed down.. through timing reduction, adding fuel(richening), or adding octane.

Its a great learning experience to see someone running higher boost numbers on pump gas and making power.