I see lots of people that say they just want to run pump gas and not run water/meth. I ask them why they would do such a thing when you can get a kit for $200, and I see things like, "I'm only going to be running 8 PSI".

This was with what was supposed to be an 11 PSI spring. It would coil-bind before the wastegate could open more than 20%. 93 octane, straight blue windshield washer fluid (70% water, 30% meth). If it wasn't for the water and methanol, I would have been picking up my engine off of the side of the road.

I've driven the car 1500 HARD miles since this happened. Still runs great. $200 for a water/meth kit is about the best insurance you could ever ask for...




For those of you who aren't sure what you're looking at..
That's 29.5 PSI with a 15.1:1 AFR on pump gas. Topped out a 3 bar map sensor with AFR lean enough to cause detonation on an unmodified engine.

 

Wow...thats a serious boost spike. What was the cause of that?

I also agree, I'm on E85 alone, but running straight 93 pump gas just seems like the prefect recipe for headaches.

 

I had been driving it with a 5 PSI spring and a manual controller so I could run around on 20 PSI.

Decided to put more spring into it and then drive on 11-12 PSI and turn the controller back up when I wanted the 20 (doesn't hook on 20 PSI on the street). Tossed in the 11 PSI spring. It would bottom out and fully collapse while the wastegate would only open a quarter inch. Boost spiked pretty hard, car felt like a rocket. Once I got 20 mins on the datalogger I closed the laptop and drove for another 90 minutes. Got home, opened the laptop and checked the logs. Thats when I seen this.

 

Where are you guys getting $200 dollar meth kits?

And if I can infact get a decent setup for that price, where do I look for more info on nozzles, mixtures, etc? Trying to make my SBE ls1 stay alive. Thanks in advance!

 

http://pages.ebay.com/motors/link/?n...662992&alt=web

I've seen them for $200 shipped elsewhere.

 

Did you have the kit installed when this happened? I was curious what effect it had on the AFR #'s when activated, if the 02 sensor read the meth
I can set a boost level on my Holley HP, I use that as a safety step while I play with the controller

 

Alky Control and a straight meth is a better way to go

 

I run an Alky Control kit and 100% methanol. The kit was 400ish and methanol is $6 a gallon but that's way cheaper than my $6000 forged shortblock.

 

Absolutely. Still use it even on my new flex fuel setup.

 

How much fluid are you spraying? Looks like you dropped the timing a ton at the higher boost levels too. What was it at?

 

Of course I had the kit installed when this happened, its the only reason my engine is still running.

AFRs don't change much. I can post up a couple of pics of a log to show you where it activates. With a 30/70 mix my AFR barely moves at all.

With straight methanol, I wouldn't have gotten an octane boost high enough to keep this from detonating. I may have gained 5 points in octane at best. As a chemist by trade, I think that spraying so much water was keeping cylinder temps down enough to prevent detonation, or at least keeping the pistons cool enough so that if detonation occurred, they wouldn't crack like these pistons are prone to when super-heated.

I have since made the swap from the 'blue' washer fluid to the 'purple' washer fluid, which is almost a 50/50 mix at the same price. I think I'm giving up a little too much power running so much water, and I don't think the safety margins are going to change between a 30/70 and 50/50 mix.

Single 10 GPH nozzle. I keep timing around 14* on street tune (14 PSI this time of year). Anything over 210 kPa and I drop boost to 12 degrees. I didn't pick up enough at 14* and 20 PSI on the dyno to warrant the risk. I picked up 30 ft-lbs peak, but only 10 HP, and this thing is already enough of a torque monster.

 

Not suggesting more timing, just that less timing helps a ton with anti-knock. I know Buschur ran 0* timing at peak torque on his 800+whp pump gas build and ramped it up to about 8* up to 8k. 30+lbs of boost. (smaller engine, but same idea)

I have my timing table set to 5* above 27lbs just in case.

 

Joe,

Are you running it in front of the turbo or in a charge pipe?

 

Hp tuners doesn't allow us to set timing up that high in the kPa range. It think the table tops out around 14 PSI.

GTfoxy, it's in the charge pipe fairly close to the throttle body. I don't like running that much water % pre-intercooler.

 

I was trying to understand the screen shot, hard to read for me, but the sec box has the 303 KPA and showing 15 AFR's-I guess I was expecting to see something like 11's if meth activated, but in reality it doesn't show up in those #'s
Good info, I know around here they use a winter blend, I think it prob changes things around

 

I have the base single nozzle aem progressive kit and run blue washer fluid. my afr is 11.5 on gas and 10.8 when spraying.but it does not slow my car down so I just leave it there. we will see what it does when I turn it up.

 

The whole point of the post was that I overboosted, went incredibly lean, and my engine is still healthy. I wasn't expecting it to magically change my AFR to 11:1, but keep it alive at 15:1 and 30 PSI of boost.

 

Joe,
Great example of the safety factor of water. So many threads argue the merit of performance of water vs straight meth however, the fact that it can save a very expensive build is often overlooked.

Water injection:
It was good enough for 1940's fighter planes, it's good enough for me !

Alky control & 50/50.

 

Is 15:1 enough fuel to burn the motor down?

 

That was lean enough on pump gas that at 30 PSI, I should have filled my oil pan with chunks of 8 different pistons and rods. You don't blow an engine running too much fuel (generally), its not running enough that is the problem.