I know everyone says not to do this... BUT I see everyone that is spraying meth with radix combos (42# injectors) have significantly lower injector duty cycles and more timing.

I want to run a 2.9 pulley, from a 3.1 I have now. Thoughts?

 

I'm running a 2.8 pulley on my setup. My IDC's at 6300 RPM at WOT and 8.5 psi are about 120%....but I haven't been running lean....actually been running rich, like 10.5-10.7 AFR.

I'll be spraying meth again once I have some time to tune for it. I'm hoping to get my duty cycles back to a more comfortable level.

 

Crank your present AFR up to around 11.5 thunder and your idc should fall to around 105%. Then the meth will get it further down from there. IMO

 

I have a set of larger injectors I had planned on installing due to duty cycles nearing 100% with the 3.1 pulley I was running. I have not put them in. My IDC's with meth and 2.9 pulley, about 8.5 psi are in the 70's. If my meth injection fails I will go kaboom lean at WOT. The truck has never run better, even being rich in spots that I can't tune out. Meth injection has cured all the little spots of KR I would see occasionally and keeps the IATs more consistant. Leveling out the timing. The truck is not only faster it is consistanly faster.

I have not run it long enough to speak of blower wear. It is a pain for me to get the methanol, carry around spare, and remember to fill up.

I recommend it but do it right. A good kit. Knowing that if it fails chances are you are going to trash your engine. Knowing that you will have to tune for it. I would not do it without a wideband AFR gauge.

 

Good advice! What kits would you recommend? How does the Alky Controll rate?

 

Alkycontrol is what I have, I have been very impressed with both the quality of the kit and the level of customer service that Julio supports.

 

I keep changing it, but the more it cools down here the richer it runs

I guess I'm trying to hit a moving target right now. If the meth levels out my IAT's I should be in good shape.

 

you guys probably know this but there really is no such thing as 120% duty cycle. once it hits 100% that means they are wide open all the time also known as static(not moving).

i would guess i pulled 20-30% of my fuel after i turned my meth up. i know if i have a meth delivery problem things will get ugly fast but there are lots of parts on our trucks where if they fail at the wrong time the motor might go boom.

 

yep, but it is just a gauge of how bad things are, eeerrr how bad the injectors need help. I mis-spoke earlier, I was looking at old files, I went from 105% to 86% with 100% meth.

 

NOW (after popping a motor) I have my dynojet wb turn on a warning light and set off a siren if my a/f goes leaner than 12.0:1 over 3000 rpms....hopefully that will prevent a blown motor if a pump fails or the alky fails