Im saying you would need to modify your tune when you add the meth kit.

Dont run 25psi on a ls based motor on 93, you will most likely blow up. I think this person is leaving out a lot of details when he claims 25psi on 93. That is not good advice at all.

Alex

 

Its all in what the motor wants. Its somewhat conservative on timing but also low compression motor. Its got good head chambers and good sized cam. It all works together not only tune but combo in general

 

Correct. No where did i advise u can run that much boost on lsx motor or any motor in general. Do not put words in my mouth or read into it to much. I clearly said motor is setup for it and tuned around those conditions

 

Im not putting words in any mouths. This person is obviously new to all this, why confuse the guy and start talking about 25psi on pump gas?

Run a single 15pgh to 600whp, a dual 15 if approaching 1000whp level. Have it tuned for the meth and dont go wot without any meth. Thats pretty much it.

 

What exactly am i adjusting when tuning for water/meth?
How will my o2 react when it comes on?
What are you "telling" the pcm to do when it sees it come on?
unfortunately, with my stand alone efi setup, i can only adjust it to command a certain AFR at certain throttle (idle,part,wot,boost) positions and the map sensor (ZR1) handles load and boost based on this. I don't know what people are "adjusting" when meth comes on. Almost like different tunes for when your on meth and not. I'm able to understand it but i don't have any experience with HP Tuners or any other software that can manipulate OE software.

 

He asked when do you need meth? I answered the question. And you are wrong with meth being required based on hp level. That has little to do with it.

 

Did I miss it, or have you not told us what engine/turbo combo your running? Are you planning on 50/50 or 100% meth.

You haven’t given us enough information to make any kind of educated guess. The amount of power/boost/ timing that require “X” amount of meth/water will be different for each setup. Describe your setup in detail and we can suggest a good starting point.

When using 100% meth, it’s more like adding octane. (race gas) There is no real limit to how much you can add. Think of it as an additional fuel injector(s) controlled independently. Your ECU has no idea if it’s on/off etc. Anytime the meth inj. is “ON” the AFR will go rich. How rich is determined by the amount U spray. If your ECU can “auto correct” the AFR, you don’t have to do anything. When the meth kicks on the ECU will automatically lean the tune out to maintain your commanded AFR.

When using 50/50 its more complicated. Water cools the CC much better than methanol, but you are limited in the amount you can add. Water has no octane and is not combustible, If you spray too much it will hurt performance and drown out the spark. So you are limited to the amount you can spray. The higher the water percentage the less volume you can inject without performance suffering. Using something like window washer fluid really limits the volume of fluid you can inject.

All of it works, to get it to work well you have to do some research/testing on your setup. 100% meth usually works best because you can dump in a ton of it without any ignition issues.

 

I apologize for that,didn't realize my sig wasn't showing when i posted using the mobile site. Here's the info
2005 5.3 gen 4 gapped
799 heads with BTR 660 kit
ls9 gaskets , head studs
Tick turbo grind 217 227 637 623 114+4
80lb FIC bosch, 044 pump -8up -6dn
Single On3 76, Precision PW66 gate
Tial Q 50 BOV
2" ID log manifols, 2"y, 4"dp
MSD Atomic LS efi
4l80e auto/man, Jakes D3 brake
lemme know if you need any more info.

Lookin for 7-750rwhp 9.80s-10.20s
this achievable with my setup in my 70 chevelle 3700 race weight?

 

Difference between a 9.80 and 10.20 is pretty huge. Maybe 10.20’s around 23lbs, but that’s pushing it on that dinky turbo and pump gas. The 0N3 turbos have the tiny 65mm exh wheel. I’d grab VS racings new 88mm T4 with the 83mm turbine wheel. It’s $525 bucks and is much better suited to your goal IMO.

If you plan on 50/50 2 12gph nozzles are about right for a 5.3 @ 23lbs and 6500 rpm. You need to factor in the pressure VS flow. Nozzles are rated at 100psi. So 2 12gph nozzles at 300psi flow a lot more than 24gph.

Here is the formula to calculate flow rate vs pressure.
To get a true 24gph of flow at 200 psi you’d want 1 8gph and 1 9gph nozzle.

You also have to look at the pumps capability of flow/pressure. The big re-circulation pumps advertised at “300 PSI” are MAX rated @ 30GPH @ 200psi. They don’t list the flow at 300. I’m assuming that’s because it’s really low! You can’t keep adding nozzles and ignore the pump. Pressure will drop significantly, throwing your flow rates off.

If you plan on 100% meth I’d jump straight into 1 10gph and 1 11gph nozzle @ 200psi. Which is the max most single pumps will support.

 

First off, thanks for taking the time to help,i appreciate it and im sure others do as well.
Yea,i was a little afraid i was gonna be limited on that turbo and i do plan On changing it. But it's definitely good to get my feet wet with. Denmah (Matt) has done quite well with his but he's waaay lighter.
Ill check out that turbo,sounds good.

 

What/which ECUs can 'Auto Correct' ? this would require the ecm having access to a Wideband as well i would think.

 

This is actually a good thread, so keep it going!!!

I'm wondering if the TYPE of water/meth system makes a difference on how much gets injected.

For instance, I run the Holley EFI system and their water/meth system. It uses solenoids to inject the water, much like an actual fuel injector. I have a a single 1000cc (~15-16 gal/hr) solenoid and cant really inject more than 10% of total fuel flow, and at that rate my solenoid duty cycle is less than 50%. At 17psi I use about 500lbs/hr of fuel, so another 50 lbs/hr of meth/water is going in with it.

I always wondered how some guys can run 2 15gal/hr nozzles. If I inject 12%-15% I can get the motor to break-up. Is it possible that my system atomizes the mixture better thus requiring less of it??? My AFR is inline as the ECU adjusted for the difference to keep things at 11.5:1.

 

I use a Snow Performance progressive controller with a 50:50 water meth mix. It works great.

As far as "when" to use it. It all depends on your current IAT level vs how much more boost and timing do you want to run. Intercooling, and a lower CR will aid in keeping things safe.

If you are getting close to the limit I would say add it. Meth is the cheapest way to keep things safe fuel wise. Snow Performance has different setups for different power levels on their website. I don't think they are a sponser so I won't post up a link, but it is easily found.

 

My MSD Atomis LS works this way. It runs on a wideband and "auto corrects" based on any AFR i tell it to. I also run a separate Innovative SCG-1 boost controller/wideband and it confirms for me what the ecu is doing along with boost control.

 

IATs are in check so far,under 100*
but then again, its not 94 and humid out yet either. Id like to safely turn this sucker up to 18-20 psi at some point soon to see what its got/potential. Been hitting 11-13psi on the street so far. How accurate is doubling atmospheric pressure to doubling HP? More theory than accurate?

 

Maybe your getting spark blow out when you increase flow because you are on the edge with the 10%? Maybe up the meth content Vs water?
Your ecu will adjust on its own when you spray?

 

Possible spark blow-out I guess but it otherwise runs perfect. I already have the gaps at .022 and cant see needing to go tighter than that as nobody else seems to have to. My pump says 50/50 is max. ECU does adjust fueling for me thankfully. I needed to make a couple of WOT passes when I had the water/meth injection on for the ECU to learn and pull a little fuel out.

The research I did confirms that my experience is similar with other Holley users...just strange how different these systems act was my point.

 

Yea, 22-28 seems to be the range that works. Your right, every combo is just different. I gotta pull the trigger on one of these systems soon, i wanna see what this beast has got !

 

Just an FYI this is the system I run (mine is the Holley version). Interestingly, this system also has boost control which is a bonus.

http://www.alamomotorsports.com/FJO/waterinjection.html

 

Thats a pretty nice setup! Haven't seen that in my search yet.