Stock SMIC w/ meth/water injection

[My91TalonTSi]

Just wondering if anyone has ran the stock SMIC with meth/water injection on the stock lower intercooler pipe in the lower to mid 20's for boost on an EVO 3 16g.

My mods are in my profile and soon there will be an upper intercooler pipe, 850cc injectors, 255lph pump, an AFPR, and a DSM Chip Stage 3 chip. The chip will be a dual map set up with a 93 pump map and a c12 map.

How good is the lower intercooler pipe at handling a decent amount of boost? I know the stock intercooler is prone to heatsoak with a turbo like an EVO 3 at higher boost settings, but hopefully some water/meth injection can resolve that issue.

Any thoughts on this? I know this seems like an odd plan, but there is a method to my madness.

 

[kenamond]

I'm a bit curious about this, too. Everything I've read says to put the nozzle downstream of the IC, but if you do that, you can't possibly help with heatsoak. All of my college thermodynamics experience tells me that you want the nozzle as close to the compressor outlet as possible to maximize evaporation of the spray (that's where the air is hottest), but maybe there's a good reason for locating it after the IC. It would seem that the pre-IC nozzle would help keep the IC cooler.

 

[My91TalonTSi]

I'm a bit curious about this, too. Everything I've read says to put the nozzle downstream of the IC, but if you do that, you can't possibly help with heatsoak. All of my college thermodynamics experience tells me that you want the nozzle as close to the compressor outlet as possible to maximize evaporation of the spray (that's where the air is hottest), but maybe there's a good reason for locating it after the IC. It would seem that the pre-IC nozzle would help keep the IC cooler.

Nitrous jets would be mounted after the intercooler,right? You would think meth and water injection is the same way.

 

[Rice Over Wheat]

You don't want the nozzles spraying before the ic because of the whole purpose of the ic to cool the hot charge. The atomized mist will start condensing to droplets inside the intercooler instead of being converted to gas as easily. I put my dual nozzles about 3 inches apart on the tb elbow. You can do the same with stock ic piping. If you still have the soft oem piping, get some dejon tool hard piping to replace them.

 

[kenamond]

Since posting above, I read that WI thread that was 10 pages and spanned 3 years (took me a couple of days to chip my way through it).

One guy on that thread put a smaller nozzle upwind of his stock SMIC to help with heatsoak. The majority of the water/alc was injected into the TB elbow. He chose the nozzle sizes so that he'd get the correct/desired total flow. He said that it really helped with the heatsoak of the small stock SMIC. I figure with that setup, you'll not cool the IC airflow down enough to get condensation in the IC, but you'll help with the heatsoak. Also, a toggle/override switch in the cabin that turns on the sprayers has helped folks cool down the IC between runs. Maybe a separate nozzle upwind of the IC could be triggered manually just to handle heatsoak, but the rest of the nozzles would be triggered normally.

I've been wondering why the setups don't use a similar philosophy to the fuel rail and AFPR. If you have a pressure regulator in the injection system that lets the water pressure rise with boost, you'll flow more water/alc as boost rises. Since the boost is somewhat tracking the airflow, you'd want more water at higher boost than lower boost. Also, since the pressure drop across the nozzle will depend on both the boost pressure and the pump pressure, you would get less flow as boost increased if the pump pressure was constant which seems opposite to what you'd really want. I have to admit I've not digested all of the info out there on WI, so maybe that's just stupid.

EDIT: Okay, I read a bit more on the waterinjection forum, and my AFPR idea doesn't quite hold water. You can be at 15psi boost at 4k rpm or at 7k rpm, but the airflow rate is certianly higher at 7k than 4k. They recommend that you should trigger off of injector duty cycle, as that ties in both load and rpm. I don't see a cheap way to tie into that signal, though. Darn!

 

[T9S1i]

Methanol is not good for aluminum. Your IC is made of aluminum.
Also, from what i understand, your ic can only cool so much. If you put a nozzle before the IC then its not going to cool that much more.


Edit... cant find the thread i was trying to site so im just going to delete what i wrote.

 

[kenamond]

Methanol is not good for aluminum. Your IC is made of aluminum.
Also, from what i understand, your ic can only cool so much. If you put a nozzle before the IC then its not going to cool that much more.


Edit... cant find the thread i was trying to site so im just going to delete what i wrote.

Yeah...if you inject prior to the IC and this cools the charge down below ambient temperature, the IC will actually heat the air up (not what anyone wants). I think that a sprayer on a different controller (a manual one) would be sufficient for cooling the IC down between runs.

I'd only use enough methanol to keep the tank from freezing in the winter. Some have said that the corrosiveness of methanol is significantly decreased even by minor dilution, but that's hearsay. I may even choose to use a different alcohol as an antifreeze just to keep from eating up anything in my motor (TB, IM, etc.). I know that aluminum alloys containing silicone are more tolerant of methanol, but I don't know if these are used in the IC turbulators, TB, IM, etc.

As for the OP's question, check out this thread. The guy was running 22psi on a 16g with a SMIC, but it wasn't the stock SMIC. It's a very long read to get through it all, but you'll get the general idea in the first page or two.

 

[Rice Over Wheat]

Use dual or even triple injectors spaced evenly along your uicp (I'm assuming you have hard piping). But make sure you take whatever size injector suits your setup, and divide the size by the number of injectors. I think you'd be better served this way than anything prior to such a tiny ic like that smic. Example: If you want M6 injector with 4 gal/hr flowrate, then use two M3s for dual or three M2s for triple. You'll be able to mist the charge all the way from the smic to the intake.

 

[jking29]

One of the guys in my local club has been running low 12's on a small 16g for several years with a stock smic on a 1g. He has a small nozzle before the ic and a larger nozzle at the elbow. Adding the small nozzle before the ic keeps it from heat soaking. Corrosion and condensation has been a non-issue as the water injection is only active under boost when you have a lot of airflow and it does not have time to sit in the ic and collect.

 

[Rice Over Wheat]

Doesn't that bring into question how effective the pre-ic injector is then? If the ic is not reaching a low enough temp to condense any vapor when the pump shuts off, then it must still be pretty hot. Anyway, as others have stated, according to many injection sites themselves, pre-ic is not recommended because of methanol/aluminum reaction.