Wow so now that the temps have been warmer, my hfs-1 works just fine....I'll have to play with this over next winter I guess...

 

bump!

Car has been ROCK SOLID this summer and fall w/ HFS-1, not a hiccup. Converted to speed density and was logging/testing at around 40°F 2 weeks ago w/o any problems. Last week temps dipped down to ~0°F and now back up to ~15-20°F, I'm only getting 3 bars on the flow meter, sometimes spiking to 6 or 7, but always back down to 3.

Any ideas?

 

Hey, can you give me an reminder, did we resolved the low flow issue?

 

check the fittings on the high speed valve and the flow sensor. and also the pump. you have to check them when the pump is running though, it will be very obvious. i've seen way to many kits with the quick release fittings leak after time. it makes the flow sensor irratic, and reads differently under different conditions. replacing the quick releases with the compression fittings has solved all the problems except for the pump. in that case there is a brass coin thing to replace some plastic crack pressure valve things. it has solved the pump top leaks i've been seeing.

 

I've checked all of the fittings, nothing is leaking. This is temperature related. AFRs are tuned to ~11.8, and I've seen as lean as 12.3, currently running a 1.0mm and a .9mm nozzle.

I don't think its a flow sensor problem, since the AFR is getting leaner. It's got to be temperature related, but I can't figure out if its the increased viscosity thing or what. My pump and tank is in my trunk, in the fender. Perhaps if I could warm it up somehow it would resolve this; but that seems kind of silly.

 

I have one guy from Canada also have this problem when weather turns cold. If I can find a gauge, you can pressure test the pump, set at when cold. I am keen to find this out, it has been puzzling me every winter.

 

Awesome, I'd love to test the pump somehow, def let me know. I'm not in a huge rush, thanks to tephra I can simply flip it off and still have plenty of fun with the car

 

Anyone know what this graph looks like with 50/50 meth/water and scaled down to 0°F?

*edit* here's a start:
http://ddbonline.ddbst.de/VogelCalcu...ulationCGI.exe

 

What material are your lines made of? Meth lines that is....

 

I use the standard lines that come with the aquamist kit, not sure exactly what they're made of, but I'm sure they're meth appropriate

 

I know it would require a small amount of work but may be a solution for you. Switching your lines from nylon to teflon pfa(doesn't kink like nylon,temp resistant tubing). It would be a good investment vs the generic stuff.

You can get it at mcmastercarr.com

 

Thanks, but I don't think the lines are the issue; perhaps richard can comment on what they are made of

 

*think*

 

These are list of possibilities:

1. Pump changing pressure
2. Nozzle size reduced (freezing of the tip)
3. Increase viscosity of fluid reduce flow through an fixed orifice.
4. Lift of the inline valve reduced
5. Flow sensor reading error

Which is most likely?

 

Is there any other info or pattern to this? Is it more frequent at after startup, do it more, say from a light roll-on in a higher gear as opposed to in every gear from a standing start, etc.? Just trying to narrow down different possibilities.
Sometimes a pattern will arise. At first guess I'd say #2 or #3 from Richards post, but more data is needed.

Maybe the vent on the tank? Something to do with the location of the tank allowing the vent to partially plug in cold weather creating a vacuum? Probably not, but just throwing ideas out, might shake something else loose.