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]

It is axiomatic that if you are seeking more (knock limited) power through higher boost then reducing CR is one of the better ways to facilitate this quest. IIRC, the 4 bar turbocharged F1 cars of the mid-80's had CR somewhere around 6:1.
If the gasket you installed was thicker than the factory gasket, then, all else being equal, the CR was reduced as a result.
If the 5 layer gasket is actually thinner than the factory gasket, and you knew this when you installed it, and at the same time you were seeking significantly more power through higher boost, then you were shooting yourself in the foot.

I forgot what I was going to say

 

[Nitr0EngiEx]

I worded that wrong my thicker gasket lowered compression not raise it. I knew it would lower compression some and was stronger.

 

[patprimmer]

In my opinion a thicker gasket is by far the worst way to lower compression as it also reduces effective quench.

Reduced dome height on the piston or a deeper small dia dish of increased volume close to the spark plug at TDC is a much more effective route in my opinion. Later closing of the inlet valve may also help, depending on where it already is and unless you increase duration, later closing is also later opening which may be counterproductive.

Regards
Pat
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[dgallup]

You have to be really careful changing the combustion chamber shape in these DI engines as the combined effect of fuel spray/timing and air motion greatly affect the combustion. You are not dealing with a semi-homogenous mixture like a carb or port injected engine. All the mixing & evaporating is taking place in just part of the compression stroke.

And I'll say it again. NOBODY is designing OE fuel systems with methanol compatibility in mind. It might take awhile for the problems to manifest themselves, but they will.

 

[Nitr0EngiEx]

i have let go the idea of using methanol

how about octane booster how many bottles can i add and what brand.

how many bottles would it take to get to 100 octane on 12 gallons.

 

[evelrod]

"Octane boosters" are a crutch. If you like hopping around on "one foot", go for it. I tried just about every brand available and they all pretty much suck.
Glad you gave up on the methanol...I ruined a nice pair of carbs, even with acetone/gasoline flush.

In my opinion a thicker gasket is by far the worst way to lower compression as it also reduces effective quench.

Agree 100%, Pat. In addition, a thicker head gasket can limit the ability of the fire ring to seal the combustion chamber without resorting to "O" ringing the block. Old school stuff that I have not done in a while, even on high boost and 16:1 CR engines.

I chased similar problems when building an all out 2.3 Turbocoupe in the early 80's. Managed 290hp at the wheels on pump gas, but more was probably available with today's technology. At some point you are just going to need to go to the higher octane fuel if you wish to continue power increases. It's expensive, but considering your goals, I think it's just about the cheapest trick left to you.

Rod

 

[Nitr0EngiEx]

whats the best way to convert 22psi @ 350 Grams/second into CFM ?

 

[Lou Scannon]

350 g/s of air ~= 630 SCFM of air (22psi is irrelevant in this conversion)

FWIW, I fully concur with my learned colleagues above on quench, chamber shape, and thick headgaskets. I'll defer to dgallup on the subject of gasoline diluted with methanol, as he seems to be more connected with that aspect of the industry than myself.

I forgot what I was going to say

 

[Nitr0EngiEx]

you guys have been incredibly helpful i think i thanked most or all of you for your replies.

you wont believe the crap i have endured on the forum specific to my car platform everyone is a bunch of jerks and instead of answering my questions about tuning they flame me for asking the questions and not reading the entire internet. I know how to research things and apply them but sometimes the information is platform specific and cannot be had simply by reading, for not everything applies to your applications. Thus the only and best place to inquire about my car and the software i specifically use to tune can only be answered by this group of people where only a small amount really know how to answer my question and the ones who dont just talk junk.

you would think i would get more support going the route i have taken to build a motor and go for higher power which noone has truly broken 500WHP on this car because its soo hard to do.

 

[1gibson]

Reduce full load timing until high EGT's become a problem, add some back in. Then add boost from there.

Look at other DI engines of similar displacement (Cobalt SS for example)

 

[Nitr0EngiEx]

if i am seeing 1400 on my egt gauge which is after the turbo in the downpipe like 6-8in after turbine outlet. how hot is that coming out of manifold runners

what temperature is considered dangerous ?

 

[MikeHalloran]

If you're going to use EGT for tuning, measure it at an exhaust port, or as close as you can get. You'll be amazed at how much heat the turbo removes from the stream.



Mike Halloran
Pembroke Pines, FL, USA

 

[gruntguru]

"i have let go the idea of using methanol

how about octane booster how many bottles can i add and what brand.

how many bottles would it take to get to 100 octane on 12 gallons."
If you are thinking of spending that much money there is an obvious solution to all your problems. Go talk to a supplier of racing fuel (VP or such) and select a fuel to do the job.

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

 

[Nitr0EngiEx]

At the local race shop i saw them advertising some form of ethanol, the same place i buy my methanol for my water/meth kit.

I dont know what form they are selling it in, but any ideas of what form it is in, and what do i need to mix it with if its pure.

 

[Rob821]

Unfortunately I have been in your postion. The standard injectors will not flow more that about 330-340whp(Dyno dynamics). They are also wall guide injectors - meaning they spray onto the wall then onto the piston top before heading back to the chamber. The factory pistons have mouldings on them to direct the fuel towards the chamber.

Now I'm not sure if the wieseco pistons have this moulding but it will be very beneficial. The other thing to note is that there will be huge amounts of fuel at the outer edges of the chamber meaning squish bands will be highly useful in reducing knock(which you have reduced by using a lower comp headgasket).

The only way from here IMO is to modify the manifold to use 4 extra injecotrs and use both port and DI injectors. Then you can add methanol or E85 or whatever on the port injecotrs. I definately wouldnt be using methanol or e85 with those HP pumps.

 

[Nitr0EngiEx]

i have not maxed the injectors yet i can still get the car to run rich as hell. I am and always will spray the methanol into the intake manifold which is what everyone does on this car and it works very well for the reasons i stated before with all the build up on the intake valves and easy knock conditions.

I could always add 4 separate alcohol injectors in each of the 4 runners in front of valves, and with that I could plug off the existing nozzle because it would be too big. I dont know but if we can spray it safely the way me and many others have i could just spray more and make it capable of flowing enough for what i need

Now for you guys to come correct me and tell me why this wont work I am listening. and I also ask if I do it this way I wont need acetone right ? it will mix when compressed in cylinder or as well might even evaporate from heat well before cylinders ??

 

[Nitr0EngiEx]

the Wiseco have the exact same dished shape as the factory pistons but have way better skirts with a special coating on them.

So even tho my new head gasket is more stff and more like metal vs the flimsy factory gasket its bad ?

 

[patprimmer]

If it's thicker it's bad.

If you want to use that gasket you need to take the extra thickness off the top of the block so the piston to head clearance remains as the factory set it or just maybe a little tighter even is better.

To reduce compression, increase the depth of the dish in the piston. Do not increase the dia of the dish without very careful consideration of where it gets close to the head and what that does to turbulence from the squish as the piston approaches the head.

You can run any fuel you like as a supplementary through a separate system so long as that system is designed for that fuel.

Can you tune the ECU on the OEM system.

Can you replace the OEM ecu with something like a a Motec.

If you must use the stock OEM system and a supplementary system, an MFI system as the secondary might be possible. Something like those made by Enderely or Kinsler or Hilborne. They are simple and reliable and dead easy to tune once you understand how they work, although they have zero self correction for anything and as a supplementary rather than as a stand alone, you would be pioneering new ground.

If the OEM will fuel as though the engine is std and not self correct to a point, you can add extra fuel to match extra airflow the OEM won't recognise via a purely mechanical system, however it will only like WOT or closed throttle operation.

For a DD the transition from OEM only on part throttle to MFI implementation on boost will be real tricky to work out.

If I used supplementary MFI, I would use it with methanol.



Regards
Pat
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[thruthefence]

If there's a small general aviation airport near you, go buy five gallons or so of 100LL avgas.(STICKER SHOCK WARNING:

http://www.100ll.com/)

Add it to your street gas at 20%, ie 1 qt to a gallon of 93 octane auto fuel. There's enough lead in it (even at it's "low Lead" status) to raise your "streetable" octane. Avoid the temptation to run the car on straight avgas, even if you can afford it. It's the combination of the octane improvers in the auto gas, combined with the small amount of lead from the avgas that does the trick. Remember also, that the avgas has no road tax on it. Usual disclaimers apply.

 

[patprimmer]

The lead will also quickly kill your catalytic converter if you run one.

Even if yo take it off and only fit it for inspection, lead in the system will wash through for weeks even when running only unleaded.

Regards
Pat
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