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WeezyRT
03-16-2008, 02:08 PM
How much boost can I SAFELY run before needing to go meth injection or intercooled?

Ill be running a forged 408 (cast crank though) and tuning with SCT PRP. I had planned on doing 16psi, but then realized most (if not all) guys running that much were intercooled, meth injected, or both. Could I get away with 16psi with no meth/intercooler or am I pushing my luck?

White Turbo
03-16-2008, 03:27 PM
How much boost can I SAFELY run before needing to go meth injection or intercooled?

Ill be running a forged 408 (cast crank though) and tuning with SCT PRP. I had planned on doing 16psi, but then realized most (if not all) guys running that much were intercooled, meth injected, or both. Could I get away with 16psi with no meth/intercooler or am I pushing my luck?

Well since you did not state your method of boost, I'll assume you mean S/C.

There are other factors besides tuning for air/fuel when it comes to boost. A forged bottom end is a good start. Good head gaskets and studs are a must at 16 psi. 2 steps colder plugs will help with detonation.
IMO,, you will want to cool the intake charge regardless of the amount of boost your running. Boost equals heat. The more boost you make, the hotter the intake charge.
Without an intercooler or meth, you have to rely on A/F and timing only to be safe. That means running it rich to cool things down, which will lose HP.
With an A/W I/C,, you can cool the IAT considerably and lean the A/F out. And meth injection will allow you to cool the IAT, and run lower octane fuel. Either option (or both) allows you to get the most out of your tune.

The safe octane level needed to support 16 psi will vary depending what method of cooling you choose, static CR, cam choice, etc.
Another safety factor is piston to wall clearance. Your piston mfg. will dictate what clearance to use.
With so many different combos out there, it's tough to say what level of boost is safe for any application. Your safety margin may differ from the next guy's.
We could give you more specific advice if you could provide details like, P/W clearance, cam intake closing degree, static CR, bore and stroke, method of cooling the IAT, actual boost, and actual A/F. But your not that far along yet.

Five9Dak
03-16-2008, 04:40 PM
If the truck doesnt race in a class that doesn't allow some sort of intercooling, it wouldn't make sense to spend all that money and not throw a 400 dollar meth kit on it to protect your investment.

WeezyRT
03-16-2008, 05:12 PM
If the truck doesnt race in a class that doesn't allow some sort of intercooling, it wouldn't make sense to spend all that money and not throw a 400 dollar meth kit on it to protect your investment.

Woah, $400? I thought it was alot more than that. Hmm... any links?

Lederip
03-16-2008, 05:21 PM
Woah, $400? I thought it was alot more than that. Hmm... any links?
I run a snow performance kit. snowperformance.net

WeezyRT
03-16-2008, 05:34 PM
I run a snow performance kit. snowperformance.net

This the one?

http://www.snowperformance.net/product.php?pk=8

Five9Dak
03-16-2008, 05:52 PM
There are even plans to do it yourself for even less. The shureflow pump (what snow uses) and jets are availble from harbor frieght IIRC.

WeezyRT
03-17-2008, 02:48 PM
So with the meth injection...it automatically sprays the meth it sees a preset amount of boost, or just boost in general?

Also, the meth/water mix ("boost juice") can you get that at a local parts store or do you have to order that?

Lederip
03-17-2008, 03:04 PM
So with the meth injection...it automatically sprays the meth it sees a preset amount of boost, or just boost in general?

Also, the meth/water mix ("boost juice") can you get that at a local parts store or do you have to order that?

There are 4 basic adjustments with a Snow kit. Jet Size-Line Pressure-When the system starts spraying and how fast it gets to full flow.

Start out with around 150psi with a large jet (for ~500hp). Set alcohol to come on around 4# of boost. Have it spraying a full blast at ~10#. If it boggs, drop the jet size. Make minor adjustments with psi. Spray as much as you can without bogging the engine.

Rtspeeddemon
03-18-2008, 11:58 AM
Also, the meth/water mix ("boost juice") can you get that at a local parts store or do you have to order that?


You can buy straight methanol and then just mix it about 70% meth to 30% water. Some use straight meth but my tuner says no added benefit of going stronger than 70%.

grapejuice1998
03-18-2008, 03:34 PM
You can buy straight methanol and then just mix it about 70% meth to 30% water. Some use straight meth but my tuner says no added benefit of going stronger than 70%.

I heard you can use windshield washer fluid??? Is that true?

WeezyRT
03-18-2008, 04:21 PM
I heard you can use windshield washer fluid??? Is that true?

It seems so... I read on the snowperformance website that some windshield washer fluid is 40% methanol.

This is off the website: "SP sells 50/50% methanol/waterMethanol as Boost Juice™ (see products). Methanol can generally be purchased where racing fuels are sold. Also, most gas line dryers like "Heat" are simply Methanol. Suppliers of industrial chemicals can also supply Methanol usually at a higher price than fuel suppliers.

If all else fails, most windshield washer fluids are up to 40% Methanol and 58% water. Although most contain some glycol and detergent(less than 1%), most windshield washer fluids are up to 40% methanol. Try to find one that indicates "contains methanol" and is rated to -20ºf."

Rtspeeddemon
03-18-2008, 04:47 PM
I heard you can use windshield washer fluid??? Is that true?

You can but must stay away from any that have detergents in them like the summer blends.

Lederip
03-18-2008, 05:14 PM
I heard you can use windshield washer fluid??? Is that true?
Just as long as you don't use that Texas windshield washer fluid. You need some good Canadian or Michigan stuff. :jester: Something good for 20 below.