Max.HP on 95 Octane with WI ?

[DuMaurier 7]

As the subject asks , I'd like to know if there's anyone here who (if anyone) is SAFELY AND RELIABLY making big power , like around 600 RWHP @25psi on pump gas with the aid of W.I., I will be ready for the dyno soon and with my current set up , I expect over 600 RWHP , but I'd like to do it on pump gas without recking my motor. :twisted:

[TunerM]

It depends on what car/motor you are attempting this with, but yes it is absolutely possible.

[JohnA]

Some people don't need anywhere near 25psi to make 600bhp on their Vipers.
And they certainly don't need water injection.

[DuMaurier 7]

I dont have a 7 leter V10 , I have an RX7 with a modified two rotor 13B Wankel rotary engine , its fully built , and modified , I has twin Garret GT3071R turboes on it with all the supporting stuff ( monster fuel system , programmable ECU etc ) with it . These motors are known to be capable of very high power levels in a small package .

[JohnA]

Nice, at least we know what engine we're talking about now. :smile:
W.I. will help you get the maximum out of whatever fuelling you've got, because you won't have to be running pig-rich just to cool the chambers down a bit.
But I doubt that anyone can come up with an absolute bhp figure and say "95RON will give you up to XXX bhp", because it doesn't work like that.
Unlike the flow capacity of a fuel system (which can be used to extrapolate rought max power figures), RON only indicates resistance to detonation.
Wankels are very sensitive to even tiny traces of detonation, as I'm sure you already know.

Have you got any ideas as to where the WI nozzles would be placed? What do people in the wankel forums usually do? It would be interesting to have RX7s in the "Car Specific" area of the forum, because they are so different to piston engines.

[DuMaurier 7]

I am not asking anyone to tell me what I should get with 95 RON and WI , I am just asking how much was made by whom using 95 RON and WI , an idea of their setup would be ok too .
For now I have a single 1.0mm nozzle fust after the IC and about 3-4 feet from my TB , a lot of people put their nozzles a few inches away from their TB , I am not sure how good my nozzle placement is , but I may put in another one closer to my TB.

[JohnA]

What country is that then?
Do you know what is the MON value of the fuel you use? That is more important for detonation-resistance, and it varies with countries.

As a very rough guide, on an engine with the airflow like yours, if you use a 50/50 water/methanol mix in a 10% water/fuel ratio you should experience the effect of 5 extra RON (usually it's even more)

You may also be interested in this document:
http://naca.central.cranfield.ac.uk/...a-wr-e-264.pdf

Not totally in the league of a blown wankel :lol: but still indicates the magnitude level of octane increase you might experience.

In piston engines, if water atomisation is good it is not unusual to experience knock resistance half-way between what you've got and full-blown race fuel (110 octane)

[DuMaurier 7]

I am from the caribbean , Trinidad to be exact , we make our own fuel , its rated at 93 RON minimum . I may try the 50 / 50 alco and water thing , I'm not sure yet , but I am a supervisor on a 15ooTPD methanol p[lant , so getting the stuff isn't a problem.

[JohnA]

Ah, the gains might be even higher then.
I remember a friend running a high-boost supra in India, where the fuel quality is suspect at best :wink:

He had audible knocking all the time, with basic WI it stopped completely (0.8mm nozzle before the throttle)

The effects of octane increase are more pronounced on lower-quality fuels. The better the fuel, the harder it is to increase the octane with such methods.
If you have access to toluene (to mix in the fuel tank) then you're laughing, that is the DADDY