Higher boost and E85 or Methanol 9

[Nitr0EngiEx]

I have a mazdaspeed 3 with a built motor and a Garrett 3076 turbo. the engine is 2.4L Direct injection, and holds a fuel rail pressure at 1800 psi kind of like a diesel just not as extreme. I have 9.5:1 compression.

I want to run 400WHP Daily driver but this engine runs on 93 octane pump gas and I am spraying a 7 Gallon per hour nozzle of 50% Methanol and 50% Water into my intercooler piping about 16 inches before my throttle body.

My EGT reads about 1200 F at WOT and i run about 11.6-11.9 AFR. The turbo is flowing about 350 Grams/second of air. at 22PSI at 6k rpm. I am getting some engine knock and am very concerned about tuning the timing higher and not catching damage to the engine. I want to beat on it every day as safely as i can and i have a fully built motor so between the 93 octane gas with spraying methanol it should be enough but I don't feel it is and i do not want to spray more its terribly difficult to introduce the extra mixture of fuel into the intake tract and i cannot program the ECU to read it, it can only compensate.

The MAIN Question: E85 is NOT available around me, 99.9% methanol is available. 106 octane is available but costs way too much for daily driver. Should i just start putting Methonal in my gas tank with the 93 octane because i cant buy E85 ? what other options are there. I want to go up to 26-28 PSI and I want a more solid solution then trying to spray so much alcohol.

And What AFR Would be good for this application

*(please remember I am direct injected and my AFR runs a tad higher then the conventional port/intake manifold injections that have time to atomize pre cylinders and dont require so much fuel pressure, and have more time to spray)

 

[Lou Scannon]

If your EGT is post turbine it is pretty much meaningless, especially for short bursts of WOT.
If you're knock limited now and you want more power without more knock, you will have to impose measures to increase knock margin, as you are contemplating. The path to more power is more boost pressure, as this results in more air available for combustion. To mitigate knock due to increased boost pressure, you have available the options of:
-higher octane fuel
-lower AFR (to a point, probably around 10:1 or equivalent, if fuel is not gasoline)
-more effective intercooling, if feasible
-retarding spark timing (to a point, EGT may become a limiting factor, but you would have to measure it pre-turbo to know).
-water or water-methanol injection (to a point, where combustion becomes unstable)
These measures will actually work best in combination. The only ones you can't overdo are higher octane and better intercooling.

I wouldn't add methanol to your tank unless you know your fuel system is methanol-ready, and can tune your application for the change in AFR, and accurately control the ratio of methanol to gasoline accordingly when you add the methanol.

Also, I'd advise you, if you don't know already, to evaluate your fuel system's ability to deliver the extra fuel needed to match the extra air you want to add, especially if you choose to put a less energy dense fuel (e.g. methanl-gasoline mixture) in your tank.




I forgot what I was going to say

 

[Nitr0EngiEx]

any guess to a good AFR for my application

 

[Nitr0EngiEx]

if my fuel system is ethanol ready would it not be methanol capable just the same ?

and what are all the options for raising octane rating. For my application i should stick to spraying 50% water ? or maybe more water or more methanol

 

[Nitr0EngiEx]

god there is no way to edit posts here, but i ahve more information to add

my EGT sensor is about 14" AFTER the Turbine/Turbo in my Downpipe.

 

[Lou Scannon]

Methanol is more corrosive than ethanol but ethanol ready is probably Ok for methanol.

EGT 14" after the turbo doesn't tell you much about what's going on with the temperature limited components, e.g. exhaust valves, exhaust manifold, turbine & turbine housing.

Not possible to guess ideal AFR over the interet. Too many variables. I would suggest 10.0 and 12.0 as WOT tuning limits, for an aggressive power goal as you have.

I forgot what I was going to say

 

[gruntguru]

To add to hemi's list for mitigating knock - reduce CR.

Adding methanol to the fuel has several benefits - higher octane, reduced AFR sensitivity (you can run a lot more excess fuel), better charge cooling. Mixing can be problematic. A little moisture absorption (methanol is highly hygroscopic) and it won't mix with gasolene. Adding up to 5% acetone will help. Methanol flow requirement is more than double what you need for gasolene ie 20% methanol blend requires 20% increase in fuel flow.

Engineering is the art of creating things you need, from things you can get.

 

[Nitr0EngiEx]

ok your a bit vague with that, add acetone to what the methanol top stop from corroding or to make it mix with gas or just add to gas alone.

isn't acetone corrosive or highly highly volatile and extremely expensive like a gallon is 20$ ?

 

[patprimmer]

Methanol and petrol don't mix. The acetone helps it to mix. Yes acetone is expensive.

Acetone is not corrosive as such like methanol which attacks metals, especially aluminium, however acetone is an aggressive solvent for many polymers including many plastic and rubber bits that resist petrol and even methanol.

Methanol is considerably more aggressive than ethanol and I would not presume an E85 ready system will handle the chemical attack or increased volume of fuel required for methanol. The extra volume of fuel is enough so that even tank vents need to be considerably bigger.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[patprimmer]

I would not spray water methanol before the inter cooler for several reasons.

The latent heat of vaporization from the water/alcohol injection remains constant no matter where you inject it, but the inter cooler is more efficient at higher charge temperature so if you inject the water/alcohol after the inter cooler you get a lower ultimate charge temperature which gives maximum suppression to knock.

Water/alcohol that lays in the inter cooler in liquid form can cause corrosion and inhibit air flow.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[dgallup]

It is NOT safe to assume that an ethanol ready fuel system is safe with methanol!!!!!!!!!!!!!!

Methanol is much more corrosive, as already mentioned. However, the bigger problem is elastomers and plastics. Methanol will cause typical fluorocarbon o-rings & seals to swell over 100%. It will also permeate nylons.

I would expect your inter cooler already has substantial corrosion from your 50/50 water methanol spray.

 

[Nitr0EngiEx]

I am Spraying the water/Methanol about 12 inches in front of the throttle body well well after the inter cooler. I have not sprayed anything on or in my inter cooler.

When i installed the methanol kit i read all the possible mounting locations and this proved to be the best place, just enough space to mix with the air but not lose its cooling properties before hitting cylinders.

If I spray CO2 or NOS on the inter cooler and cool the air charge quite a bit that wont help my knock but might make it worse right? the colder air will just make more power and not help cool anything ? I know it adds about 20 WHP, but wont help knock ?

There is a Dual purpose for my car to have methanol. From factory the car is Direct injected meaning NO fuel goes through my intake system at all but there are 2 PCV systems that feed fumes and oil and gunk all through my intake manifold and valves and also a EGR that feeds exhaust through here as well, so there is NOTHING coming through to clean all that carbon and oil and crap build up in the entire intake tract. it looks like a sewer in there normally, i need the methanol to clean it.

 

[Nitr0EngiEx]

"gruntguru (Mechanical)
15 May 11 23:28
To add to hemi's list for mitigating knock - reduce CR.

Adding methanol to the fuel has several benefits - higher octane, reduced AFR sensitivity (you can run a lot more excess fuel), better charge cooling. Mixing can be problematic. A little moisture absorption (methanol is highly hygroscopic) and it won't mix with gasolene. Adding up to 5% acetone will help. Methanol flow requirement is more than double what you need for gasolene ie 20% methanol blend requires 20% increase in fuel flow. "

What is CR

 

[dgallup]

Compression Ratio

 

[1gibson]

Maybe a different turbo is more suited to your goals. Maybe the one you've selected is already optimized, or it could be the stock turbo, I'm not familiar.

Assume the IC is air/air, maybe water/air would have greater cooling capacity, depends what you can fit.


Exhaust cutout or other means to reduce backpressure. Slightly cooler thermostat. The usual stuff.

 

[Nitr0EngiEx]

the turbos is Garret 3076R T3 Flange inlet to turbine and 3" Vband outlet and is supposed to be efficient in upwards of 28-32 psi according to their website. Now my 2.4L is kinda big compared to alot of 4 Cylinders so I think i should be ok to flow 26-28 psi and I want to work up to it maybe for track running or weekend races.

MORE INFO: to satisfy if your wondering about turbo capabilities, one time i had the manual boost controller i no longer use in my setup backwards and the restrictor pill was backwards in the wastegate setup and the turbo was spiking to 32 psi before letting back down to the 14psi spring pressure i had in the waste gate at the time. thank god i had built the motor with chromolly billet rods and the wiseco pistons Or i woulda lost my motor.

Now to Further my Flow capabilities I can completely read my Temperatures of Air charge at the inlet of the intake system and the Boosted air temps and with the methanol my boosted temps are 60-70F. Without the alcohol the temps run in the 95-100's. I live in Tampa Florida its extremely hot and humid here.

QUESTION: I have been wondering about water/air intercooling and what i want to know is is there a way to daily drive like this. my fabricator uses them in his 1000HP car at the track but he uses ice water i think and only for track running the car is for of course and he only speaks spanish so its hard to talk to him. my questions is how does it work internally and will it be beneficial to use this with regular water daily, will it get too hot after driving a bit and not be beneficial anymore or can i get one and empty it for daily use and then when im gonna race fill it up with cold water ?

 

[1gibson]

Water/air IC core, pump, front mount (small radiator) and reservoir at highest point (to eliminate air bubbles.)

It's just a closed loop cooling system. Daily driving, should stay within 10* of ambient temp.

Yes, add ice at the track if you want. This is a major benefit of using water/air. Adding "cold water" will not do anything for you. Ask your fabricator how many lbs of ice he melts in one run.

Re: turbo selection, plot it on the compressor map and make sure you're in the right place. Efficiency depends on flow and pressure ratio.

 

[Nitr0EngiEx]

so how does the water remove the heat, is it sprayed over the fins, does the water get sealed in a jacket around the intercooler and fully flows over fins.

 

[Lou Scannon]

"Methanol is considerably more aggressive than ethanol and I would not presume an E85 ready system will handle the chemical attack or increased volume of fuel required for methanol. The extra volume of fuel is enough so that even tank vents need to be considerably bigger."
Agreed, Pat. My aSSumption was that the OP was considering blending moderate amounts of methanol, but not anywhere near M85.
I also aSSume that the OEMs, when they harden a fuel system for E85, overdo things a bit, for the sake of warranty avoidance. And, US OEMs at least, have had experience with M85 in the 80's & 90's (ah, the good old days, M85 at the pump, in California at least), and I expect, though I don't know, that the lessons learned then are now being applied to E85.

Gruntguru, you are quite right, CR is a very important knob in the quest for increased supercharged horsepower. Since the OP has already "built" his motor, I left that out of my list of post-build tuning measures.

I forgot what I was going to say

 

[Nitr0EngiEx]

I was afraid to lower the CR when i built motor and lose power because this Engine platform is VERY VERY hard to get power from the direct injection systems are new to gasoline engines and are mostly applied in diesel applications, I figured mazda made the engine such High CR to make the power they did from the stock engine which makes 260 hp at crank

I did However put a 5 layer cometic metal gasket instead of the factory 2 layer piece of crap to raise the CR a small tad.

I estimate I am flirting with 400 Wheel Horsepower.