HOT RODS PUMP GAS DRAGS - WATER/ ALCOHOL INJECTION??

[TT69CAMARO]

I have been selected to compete in Hot Rods pump gas drags. I have a twin turbo SBC. The rules state that I can use water injection. I haven't done any research on water injection yet, so I thought this would be a good place to get some help!

I would like some help designing a system. I would like to know if injection into the turbos verses into the inlet pipe after the intercooler, would effectively cool the charge more efficiently?
I have alot of work ahead of me before the PGD's and need all the help I can get. Let me know what info you need to design a system and I will get it to you. Everyones help is appreciated.

You can check out my car and others on http://www.forcedpsi.com

Let me know what you think
Thanks :D

[Charged Performance]

I don't have it handy but there is a thread or two already on here about injecting pre-turbo. Past experiences with poorly atomizing systems and possibly weaker materials have not been good on the compressor. I have never been convinced any potential gains from pre-turbo spraying are worth it and think you will find that spraying somewhere in the system along your intercooler to throttle body piping will work well. Possibly right at the intercooler exit to give some travel distance for mixing prior to your throttle body since it is at one end of the plenum.

[TT69CAMARO]

Thanks for your suggestion, I will install it in the pipe before the T.B.

I've been reading other posts and gathered some info that I think you will need. I have a 374ci. engine. I make 900+hp on 93 octane at 14 psi boost, 1100+hp on 110 octane @ 20psi boost, and 1300+ on 116 octane @ 26psi boost.
How much more boost would be safe to run with 93 octane and water injection? What boost could I safely run with alcohol injection and 93 octane?

Can you recommend the components I need to buy at the boost level I can run?

Thanks

[Charged Performance]

Some additional questions to answer -

Assuming this is fuel injected - how many pounds are the injectors?

What is your IDC levels at the different tunes you described?

What engine management are you using? Are there any spare injector drivers available from that system?

You probably will want to set up a couple shurflo pumps along with Aquamist's controls either a 2c with a couple hsv's or you may need a 2s assuming you have used all the drivers on your current engine management.

[TT69CAMARO]

I am using an Accel gen 7 dfi, I am not sure if they have additional drivers but I will find out.
I have 96 # injectors

Here is where I sound stupid but what are IDC levels?

[TT69CAMARO]

Take a guess, what would a system like this cost me?

[Charged Performance]

There is no consistent terminology - it is actually my error in assuming everyone uses the same abbreviations as I do. IDC are the injector duty cycles, you should be able to log them from your Accel against rpm and boost. Your injector size gives you your fuel potential - your IDC will tell you how much of that potential you are actually using in your current tune.

Would have to look up the specs again on the Accel - but I am assuming it has 8 drivers. Depending on if you are using all 8 or just 4 (running two injectors on each) - you may or may not have unused drivers.

If you have the drivers you could work with a couple 2c's using shurflo instead of the Aquamist pumps (you need the higher flow). Probably want a full assortment of jet sizes and a couple good size accumulators.

All in all it will likely be no more than $1,000 - but you will get good realiable detonation suppression from it and relative to what your motor costs probably not bad insurance.

If you don't have extra drivers available you would want to get something like the MF2 which can drive the water injection - figure to add another $350 for that. Though you could use another injector driver - even the DIY mega squirt. I think you will need more tuning control with your setup than would be recommended for something like the fia2 though (fuel injection amplifier which would map your water similar to your fueling). You are going to really want your water injection flow to match more the torque profile of your motor. Torque levels are your cylinder pressure levels which are your largest detonation determinant.

By the way the competition is allowing water injection - but does that include water mixtures like water/methanol? They may consider alcohol as an atlernative to pump fuel (and as a result not permit it) - might be worth checking is all.

[AKWRX]

Injecting all methanol has the reasonable potential of tuning 92-93 octane pump gas as though you are using 104-108 octane, especially with respect to knock threshold.

[Richard L]

TT69CAMARO,

As AKWRX suggested using alcohol, possibly may need to check with the rules before adding alcohol to water or even running 100% alcohol.

50/50 would be a good compromise. a/f/w/a would be a nighmere to set up.

[Charged Performance]

Richard, with the aquamist pump I know that 50% methanol is the max mixture permitted. Is the mixture able to be increased when using shurflo pumps and your other components or is the mixture strength limited by other components such as the hsv also?

[TT69CAMARO]

My IDC's are between 80 and 90% depending on boost levels.

I run my injectors sequentially and don't believe there are any additional drivers, however there is a nitrous feature that maybe I could use somehow?? Has that been done by anyone?

The rules state that I can only use straight water for this event. I will use alcohol after that.

How difficult are these systems to tune in? Time is a big issue!

Is there much of an advantage in using straight water or do the real benefits happen with alcohol or methanol?

I would like to build a system that would support 1100bhp. Is that what you are thinking also when suggesting those components?

How much additional boost could I apply if using straight water?

Thanks, Chris

[Charged Performance]

The benefit of straight water alone is going to be dependent on the AFR that you would need to use to suppress knock.

My assumption is the psi's previously listed are within the efficiency range of the turbos.

Is there a fueling and timing combination that would permit you to run 20 psi on pump gas at all without knock? I know it wouldn't be near the 1100 hp you currently get with race fuel but could you do it for instance with a rich fuel setting and retarded timing?

If you can, then you will be able to tune back up as if you were using race gas.

First tune the car with its rich fuel settings and retarded timing to permit a knock free (albeit not powerful) tune.

Then add the water injection and start leaning the fueling. Your power will start increasing. Once you are happy with the AFR power and water injection is suppressing the knock that would otherwise occur - then you can start looking for MBT. It will likely be about a degree more advance than you were getting with race fuel.

Time to tune wise - you are probably in good shape. Clearly you have enough experience with your setup that you have a good feel where to go run to run. To start with think of when the water injection is engaged you have just switched from pump gas to race gas. That is in general terms it will be slightly different.

The nitrous switch is probably binary and not pulse width. If it is pulse width and can be mapped then you could use it. If it is binary on/off then you could use it to drive an fia2 system which would match your water flow approximately relative to your fuel flow. This will not be as optimum as mapping water to your torque/cylinder pressure curves but it will be a big help in moving you towards your power goals while suppressing knock.

Based on another post which brad responded to - you may even be able to do it with only one shurflo pump instead of two, brad could answer that better. With Aquamist pumps you would definitely need two and some accumulators to achieve your desired flow. Either way plan on a few jets.

The f-body below has twin turbos with no intercooler. It is using two Aquamist pumps and by my best guess of the routing 6 jets.

http://chargedperformance.com/images/nointercooler.fbody.jpg

Richard could tell you more about this customer's results but it was impressive. He previously had a huge front mount setup with no water injection.

[Richard L]

Correction, two Shurflo pumps.

The car uses 6 litre of fuel per minute and 2.7 litre of water if I remember right. Power between 1300-1500HP. Two HSVs and managed by a Autronic computer (I think) - it also has WI mapped for staging.

http://www.aquamist.co.uk/forum/startline.jpg
http://www.aquamist.co.uk/forum/drag.jpg


The Guy took away the intercooler in favour of water injection:

http://www.aquamist.co.uk/forum/before.jpg

[Charged Performance]

Who said you can't drift an f-body?

[MidEngine4Life]

That doesn't look like drifting above. It looks what happens when you try to put 1300hp+ to the ground. :shock: