My pre turbo WI
 

So I've been curious about WI for a while and finally dyno tuned my car with a pre turbo WI system I made. It's a boost operated system using one pre turbo nozzle and an ECU controlled solenoid to switch it on at 10psi.

The engine is a Japanese as-imported TII block that hasn't been run for 5 years or more, but comp tested up ok, and the turbo is a TO4B 60-1. Gas is 93 octane and I was injecting water only. Power was 431rwhp at 20psi with a fairly conservative tune.

Initially I was going to restrict water flow by controlling the solenoid with a PWM output but as it turned out the ignition system could burn the full flow through the nozzle which is 600cc per minute at 20psi. I was a little surprised as the ignition consists only of a 4 channel igniter and FC coils.

Maybe next time I might try 25psi but I reckon it'll only make another 20hp if that. A larger turbo is needed now I think.

Nice numbers, congrats:nod:
Could you share what type of dyno? Some tuning parameters would be nice.

Its fully sequential, right? There seems to be huge misunderstanding in how ignition system works. Coils are usually more than stout, question is what dwell they need to fully saturate.

Do it. If anything, it will be torque monster:egrin:

Awesome job! I'm looking into building my own setup as well. Mind sharing where you got the parts, pics, etc?

Hi, yes ignition is sequential. About 11.0 AFR and 3deg ign timing, relative only to my TDC mark which I need to double check I suspect. Actual timing must be more as the engine did knock once at peak torque at one stage when it went quite lean

Dyno is torque performance brand which seems to be fairly well on the money as far as hp vs weight/mph goes.

I will re tune for higher boost later on after a couple of meetings, if the engine is still in one piece that is! I'm not expecting much, especially as since the engine will have the old 2 piece apex seals in it and who knows how worn the top halves are! I have ordered a BW475, but I don't want to risk it on this import engine, so I'll build a decent street port block first. The goal is to eventually run into the 8's on pump gas with WI.

The WI system is fairly simple, I think the pics are self explanatory. MAC valves can be bought anywhere, and from memory the nozzle is su25a from ispray.

can't imagine your timing is accurate if it produced that figure at 3 degrees of advance. that or the dyno is way off.

that is beyond conservative.

Is that a Rice Racing kit? Looks just like one.

Nice numbers!

Yes very similar to a Rice Racing kit I believe. I don't think I've actually seen any pics of his but I know the nozzle design is the same.

I agree with the timing number being off, that's why I'm going to check the pulley. In saying that, this current ecu is completely new to me and I may have got the initial timing setup a bit out. Or possibly because the ecu compensates for the inherent timing retard associated with magnetic pickups, meaning the actual timing is more advanced than some other ecu's at the same given timing number.

YES!!! just what i been waiting to pop up!. someone finally found AND posted were the nozzels are bought! you have a PM sir!

How low do these nozzles go flow-wise?

If you could post that information it would be much appreciated.

Update:

The car went down the 1/4 for the first time. 1st run to get the feel of it was an 11.44 on low boost, 2nd run with more boost 10.66, 3rd run on 17psi - 10.60 at 126mph backing off in the deep end. 60ft was 1.68 from memory, and the tires were 26x10.5 ET streets.

Once to 60ft is sorted out and boost pressure is at the full 20psi the car should run a little quicker hopefully.

The car was driven 2 hours each way to the track and back without issue which is encouraging. And it was surprisingly economical fuel wise, which I guess is partly due to the stock porting.

grats!

but something not adding up to me..

it's a rather tiny turbo for that figure and the timing makes me scratch my head. if pre-turbo water injection really makes this much of a difference why haven't there been more people saying how golden it is?

Awesome!
Could you share race weight?

Well, 60-1 wheel is rated above 60 lbs/min. and by looking on max speed line, it can flow 65 lbs/min. at choke limit. On good setup it will support over 500 HP@crank. Also don´t forget that turbocharger is ratiometric device. Cooling of inlet air by evaporation increases its density and so even maxxed out turbo will flow more.

In regards of timing, real value will be probably higher but we know that wankel engines doesn´t need huge amount of timing. Strong ignition can cope with high pressures near TDC and so can produce really good power without excessive advance. Still will be interesting to find out true timing.

Because people are dumb?:lol:
Its really complicated, not many people can say that they really know how turbocharged engine works as whole system, from air filter to exhaust tip. And now add cooling fluids to certain places. Even less people will understand what kind of impact it has on compressor operation, turbine operation and system as whole.

I will say this: In this very example, compressor operates on the edge of the map with low efficiency. Normaly it would causes high IATs and high turbine inlet pressure. Pre-turbo WI doesn´t alter compressor efficiency, but by absorbing huge amount of heat during compression, compressor will operate at lower PR and discharge temperature. Lower pressure ratio on compressor side means lower expansion ratio on turbine side.

Shame most people won´t understand this:(

i suppose you're right, i just don't see many people netting much gains or pushing those smaller turbos to their limits. a bit of a shame considering they spool quick and have a bit of flexibility with modifications.

for pre and post WI i think i'll just leave mine post for now. has worked fine for about 4-5 years now.

Weight with driver is 2290lb from memory.

The timing is only a number in the ecu, and I'm almost certain it's not right in relation to TDC. I have not got around to checking yet.

The only reason I chose pre turbo WI over post is for simplicity sake. The simpler each of the cars systems is, the more reliable it should be.

By my calculation 430rwhp is approx 480 at the fly.
IAT doesn't go above 40degC over the duration of a run. (intercooler is a large front mount tube & fin type). I must drill a hole in one of the tanks to see if it's condesating water.

By trap speed, weight, ET (taking into account backing off) and with some common sense, I´m pretty sure you have around 400 HP@fly at 17 psi and 450 HP@fly at 20 psi. Its really simple to determine what is possible, and what is dyno dream. What kind of power would make stock port 4 port engine as NA? Surely under 200 HP. Now apply 2.2 and 2.5 PR (assuming 100% IC eff. and same VE%) and it will put you in the ballpark what can be done:nod:

Keep up good work:icon_tup:

Another update - 10.33 at 131mph. There's still more in it yet I'm sure, as that run was with a back off in the 60ft as the front wheels were starting to come up too high - we don't want a hole in the sump!

Probably one more meeting then I'll go back to the dyno and try for 25psi.

10.12 at 132mph. Plus a bent front cross member and a ground away sump plug!

I will try for 25psi at the next race I think, I'm fairly confident I won't need to dyno it before hand.

Wow! Great hp numbers and times running a 60-1 and water injection. This gives me alot of confidence for my new setup. Whats your full turbo setup like if you don't mind me asking?

Well by the trap speed & time. Im pretty sure you make over 450 FLY wheel hp.........

What do you need to know? The first post covers most of it.

Un-opened TII engine with factory manifold, t/body etc
60-1 turbo
Steam pipe ex manifold
Synapse wastegate
Air to air intercooler
Full exhaust with 2x mufflers
2x 700cc and 2x 1680cc injectors
Bosch O44 pump
TII coils
Pump gas

It doesn't get much simpler than that.

What's the turbo hot side A/R? What size is the downpipe and the rest of the exhaust system?

That's an extremely fast time for 132 trap speed, what's your 60 ft time and can you post the time slip? Also interested in the turbine housing size as I have a similar setup and best is in my signature, you would have to be getting a super crazy 60 ft or an automatic? Good job.

Also to add to the pre turbo wi debate, I ran my pre turbo wi last week at the drag strip, and the week before that I ran my post fmic wi location, same setup for everything else. There was no real difference in times or trap speeds because of the pre turbo wi. Tire pressure made a difference giving me better times but a tad bit slower trap speeds, also afr adjustments make a difference, but I didn't see any gains from the pre turbo wi

1.15 turbine a/r, 3.5in DP/ exhaust. I would have preferred a smaller a/r but that's just what the turbo happened to have on it. It still makes 15psi on the 2 step.

60ft's have been 1.33 but on that particular run it was a 1.35. I'll scan or take a pic of the time slip.

double post

10.01 with a crazy head wind, so much so that it knocked 5mph off the trap speed!
Eventually managed to get up to 133.5mph on 23psi still with the head wind but by that time the start line or the tires had gone off (not sure which yet) and the 60ft had dropped to 1.40
Earlier in the piece the 60ft got down to a 1.31 and the 10.01 run was a 1.34 60ft. The tires are getting fairly worn which may be the problem.

There was is bit of ignition breakdown at 23psi so I upped the dwell by .5ms and that seemed to fix it.

Your times and trap speeds are like what you mostly see from muscle cars with auto trans, not imports and 5 speed manual trans, great times. Any videos and time slips? Stock trans? What is your 1/8 numbers?

I'll scan time slips when I get a chance. I can't remember what the 1/8 stats are off hand.
Sorry I forgot to mention earlier that the trans is a faceplated Tremec TKO 500, which should help explain the MPH or lack of. 1st and 5th gear are still syncronized so it's quite streetable.

I don't know what that is but I guess it explains it then lol. Awesome 60 ft and et's.

If you get the point where you are breaking factory FD transmissions this is what you need! http://www.libertysgears.com/ttc.htm
Good for 800hp or so behind a 13B I reckon.

I offer adapters that allow you to bolt up your stock FC or FD bell housing to the Tremec TKO.

Can you post info on your TKO to FC bellhousing adapter? (picture, pricing, alignment features) I understand the tip of the input on the GM style TKOs will mate with a Mazda eccentric shaft.

My car's an FB, and I don't think the rear face of block to shifter distance is correct for my car. Do you have any tricks to relocate the shifter further aft on a TKO?

I have bad bearings in my FC box right now, and I'm trying to decide if I should rebuild it or go with something stouter. I'm currently only making about 350 RWHP, but I'm still tuning. I plan to bump it up as I get the tune dialed in.

It turns out I was putting in too much water! Less water made more power.
More power and new tires = 9.61 at 139mph.

Yep. good job

Awesome! Could you share more details as usual? Still on pump gas? Are you going to push it farther? I think there is still room for little bit more power, but not much.

Yes still on pump gas. The entire setup is exactly the same, only I stripped the engine, mainly before I broke it, but partly out of curiosity. It was good inside so I fitted new apex/side seals and all new springs, and waterseals. Everything else was re-used. I also tidied up the ports and dowel pinned the block.

On the same boost (23psi dropping back to 21psi at higher rpm) it made another 30hp. Taking out a bit of water seemed to be part of that hp gain, and interestingly enough it wanted 12deg of timing this time, not the 3deg before the engine was opened. Between the water cut back and the timing increase I think that must be the 30rwhp. Hp is now 460rwhp.

Between the extra hp, new tires, and no head wind this time, it ran a much better ET with a decent increase in mph. It must have run half a dozen 9.6 and 9.7 passes all at 138-139mph.

The w/gate physically won't allow more than 21psi boost, so once i get a heavier w/gate spring I'm going to shoot for 25psi or whatever the turbo will make. I'm kinda curious now to see how fast it'll go with the puny 60-1.

The BW 475 is sitting on the bench waiting for it's turn... then I'll really be able to see how far I can push pump gas...

Looking good! Thats a light car. NExt time at the track shoot some vids:nod:

how did you decrease the water flow. please share the nozzle if you got a new one. also, where did you get your reservoir. i like it.

It's the same nozzle, I just changed the pwm duty cycle to flow less water. I made the water tank to suit the space I had.

Nice numbers, send me info on the tremek and adapter plate via pm

We'll after a trip back to the dyno I now know the limits of a 60-1 turbo. It makes 29psi, dropping back to 24psi at peak rpm giving me 500hp at wheels SAE with a heap of hp in the midrange. 25psi induces a misfire right at peak rpm, so I think I found the limit of the ignition system also (there is a lot of water going in at that boost level though).

This time I used hard compound tires as the semi slicks I ran last time were melting on the rollers and had to run real flat to get grip, so the 460hp reading last time with melted tires was probably more like 470-480hp with hard tires. This seems to match up quite well the the trap speed vs the weight of the vehicle. The dyno actually read 520hp SAE however I'm going to stay on the conservative side and assume 500hp.

This is one of the best threads on this site. Pure results without BS:icon_tup:

Could you share actual water flow rate at such pressure? Also air/fuel when it happens?

I´m almost sure that someone will jump in and will start preaching about how this is not possible on 60-1:lol:

Really nice work:)

This!:icon_tup:

Water! It's awesome :D Pretty awesome that you're still running stock housings/internals :O

I have a question. What is this line with the red "???" Are the black labels correct?

https://www.rx7club.com/attachment.p...1&d=1329091802

gonna have to say the "???" is pressure(air) feed from the turbo, going to the water/air mix nozzle and then splits of going on to the tank to pressurize it (the line you have labeled "return"..) i don't see this kinda of system having a return for the water..

If that's the case, I understand why the pressure line goes to the tank but why does the nozzle want pressure?

It is an air atomizing nozzle. It externally mixes pressurized water and air to achieve a low micron droplet. The line to the tank is feeding the nozzles air needs as well as pressurizing the tank.

You need to follow Dudemaaanrx7's thread in this section. It explains the use of air astomization nozzles in this exact neumatic setup. This type of setup has been used for many years. Pioneered by Peter at Rice Racing.

https://www.rx7club.com/auxiliary-injection-173/going-make-my-own-wi-kit-807016/

XLR8 is correct, the line you have marked in red is a constant boost feed to the air side of the nozzle, and to the tank (the line you have marked as return). PWM controlled pump is not a pump, it's a solenoid valve. Boost pressure is the pump!

A quick update - this is what happens when the fuel gets real hot and the fuel pump cavitates!

This actually happened on the dyno in the previous post when the engine made 500 odd hp. Towards the end of the session the engine knocked quite badly at peak power and looking at the logs I could see fuel pressure had dropped away some, and leaned out the AFR's. Noticing the fuel gauge was low I touched the bottom of the fuel tank and was really surprised at the heat, almost too hot to hold my hand there. I let it cool down for 30min or so and ran it up again - fuel pressure/AFR were back to normal however the engine now wanted to knock at peak torque. After a few more runs of the same thing (with less and less timing) I gave it a comp test and found the rear rotor 10psi down on 2 faces. Of course I assumed it was a bent apex seal, so I thought I'd be cheeky and try to 'wear' it straight again on the road (I was in a hurry as racing was 2 days away)

300 miles later compression was a little worse so I whipped the rear iron off the engine to find a cracked corner seal and 2 dented rotor faces! Believe it or not the apex seals were still straight! At least straight in the usual way - they we're actually bent sideways due to the dent pulling the metal and deforming the entire apex seal groove. I was in a hurry since the car was meant to be racing the next morning, so I replaced the corner seals, filed the apex seal grooves, hammered the apex seals a little (lol) and put it all back together.

Data logging on the street told me it wasn't much better and still wanted to knock, so the next day was raced with less boost and no timing. The car still ran a 9.72 at 139mph, and this was done on ET streets rather than the full slick it usually runs on.

Even with the broken corner seal the engine ran perfect with no knock at approx 450hp level, however any extra boost above that seemed to be enough to make it knock. It's still running just fine on low boost, however I'm going to replace the rotor before the big turbo goes on.

BTW the fuel pump is a single Bosch 044 mounted in-tank. I'm fairly sure it's maxed out at 500rwhp and about 80psi. The hot fuel from repeated dyno pulls and little airflow must have been enough to send it over the edge.

update?