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JZG 10-29-11 04:42 AM

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.

Liborek 10-29-11 09:04 AM


Originally Posted by JZG (Post 10842042)
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.

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


Originally Posted by JZG (Post 10842042)
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.

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.


Originally Posted by JZG (Post 10842042)
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.

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

20B10AE 10-29-11 10:06 AM

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

JZG 10-30-11 06:08 PM

2 Attachment(s)
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.

RotaryEvolution 10-30-11 06:38 PM

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.

Ball joint 10-30-11 07:33 PM

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

Nice numbers!

JZG 10-30-11 08:01 PM

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.

just startn 10-30-11 11:31 PM

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

Shaman 11-01-11 08:09 AM

How low do these nozzles go flow-wise?

Ball joint 11-01-11 08:55 AM


Originally Posted by just startn (Post 10843772)
YES!!! just what i been waiting to pop up!. someone finally found AND posted were the nozzels are bought! you have a PM sir!

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

JZG 11-05-11 08:05 PM

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.

RotaryEvolution 11-05-11 08:46 PM

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?

Liborek 11-06-11 09:37 AM


Originally Posted by JZG (Post 10850965)
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.

Awesome!
Could you share race weight?


Originally Posted by Karack (Post 10851017)
something not adding up to me..

it's a rather tiny turbo for that figure and the timing makes me scratch my head.

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 [email protected] Also donīt 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 doesnīt 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.


Originally Posted by Karack (Post 10851017)
if pre-turbo water injection really makes this much of a difference why haven't there been more people saying how golden it is?

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 doesnīt 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 wonīt understand this:(

RotaryEvolution 11-06-11 12:04 PM

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.

JZG 11-07-11 03:01 PM

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.

Liborek 11-07-11 05:46 PM


Originally Posted by JZG (Post 10853144)
By my calculation 430rwhp is approx 480 at the fly.

By trap speed, weight, ET (taking into account backing off) and with some common sense, Iīm pretty sure you have around 400 [email protected] at 17 psi and 450 [email protected] 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:

JZG 11-12-11 08:49 PM

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.

JZG 11-19-11 05:22 PM

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.

calicrewchief 11-19-11 07:31 PM

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?

just startn 11-19-11 10:16 PM

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

JZG 11-20-11 05:06 PM


Originally Posted by calicrewchief (Post 10868523)
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?

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.

calicrewchief 11-20-11 06:56 PM

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

tom94RX-7 11-21-11 10:59 AM

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

JZG 11-22-11 03:59 PM

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.

JZG 11-27-11 04:48 PM

double post


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