Thoughts on NOS on a rotary

[Glenn Butcher]

Hi all,

I've been doing a little sifting around on this subject, and there isn't a lot of information out there for NOS on Rotaries.

Anyone have thoughts on this?

I know that the guys at www.cityperformancecentre.com in Sydney doubled the horsepower of a 6 port non-turbo engine a few years ago (160hp to 320hp).

I was thinking that a nice bridgeported engine with around 280hp - doubled would be quite a nice thing indeed! 560hp enough for you?

Anyways, thoughts/links would be appreciated.

[Fish]

Glenn, found this some time ago on the US forums.

NOS Infor Here! (http://www.rx7club.com/forum/showthread.php?s=&threadid=111605&highlight=NOS)

Dan

[Glenn Butcher]

Excellent Dan - having a read now.

[Glenn Butcher]

After some fiddling, this is what I have found out so far:

Is it possible?

Would it be reliable for drag racing?

Yes - I think so, running a large dose of NOS along with perfect tuning - it would be possible to achieve these figures (it has been done in one or two places around the world already). And this could be done with a standard RX-8 engine, or a ported 13B engine (with the higher compression rotors).

I have been doing a bit of research on this, and I already know that CPC in Sydney have doubled the HP of a standard 160FWHP 13B (6 port engine).

It turns out that NOS works well with the rotary, as it goes round rather than up and down - distributing the forces of the extra HP quite nicely. You don't need to strengthen conrods and pistons etc. you don't really even need to run ceramic seals, good ol' steel seals work just as well.

Quote 1:
"Fuel burns faster with more oxygen"

Quote 1 expanded:
"Nitrous oxide supplies an additional amount of oxygen to the engine that allows the engine to burn fuel at a faster rate. The additional oxygen also allows more fuel to be burned in the same time period as the engine would without the additional oxygen that comes from the nitrous oxide"

Quote 2:
"When the NOS is released from the bottle it expands and is able to absorb heat, thus super cooling the intake charge. By super cooling the intake charge, the expanding nitrous gas increases the density, and therefore the oxygen content of the intake charge"

Quote 3:
"Nitrous Oxide is not a fuel - it is a gas (similar to the air around us)."


Trouble with NOS on a turbo engine is that the wastegate (even large ones) just cannot cope with the huge volume/surge of gases produced. That is one of the reasons why most of the top rotaries running 7 and 8 second passes only use a 50HP shot of NOS - or none at all.

[clive]

Hmmmmm NOS on Rotary's !

l read a very comprehensive account on someone's NOS story on a 3rd Gen road car out in the states a couple of years ago, after 3 engines he concluded that more than a 40hp shot of NOS is all a Rotary seems to be able to cope with . ( wish l had kept the report now ) he obviously didn't think NOS was a laughing matter !!

Now for some useless info , the Germans apparently "discovered" NOS allowing Messerschmitt's to fly higher in WW2 than other fighters due to being able to compensate for the lack of air at very high altitudes when NOS was added.

How does methanol do in Rotary's l wonder as l know you actually double the amount of fuel for the same quantity of air and the real good thing is it gives a really cool burn and actually keeps the whole motor running very cool , sounds Tailor made for a Rotary ????????



All the best Clive
clive@mazdarotaryclub.com
www.mazdarotaryclub.com

[Glenn Butcher]

Hi Clive,

Yes - difficult to get to work on a turbo rotary, you really need to know what you are doing with the tuning.

Methanol is perfect, I believe that Sammy in the states uses it in his car:
http://www.kiwi-re.com/images/customer_cars/sammy1big.jpg

And Dennis Marquis runs it in his car:

http://www.kiwi-re.com/images/customer_cars/drag08big.jpg

[Steve Burnett]

Without trying to come across a little stupid..............
what about trying to find out where the red RX7 in "the fast & the furious" was build. Asuming the car used was really fitted with NOS.
I have came across the website for the place that build the Supra so im sure it would not be to difficult to fing out where the 7 was built, if you don't already know were it was done. But as I said im just adding my 2p's worth.

Steve

[Fish]

Steve, you might find that they had several engines on standby just in case it went bang. Swap outs take little time when you know what your doing.

Dan

[Fish]

Found this whilst trying to stay awake at work.

http://www.scuderiaciriani.com/rx7/N2O_install.html

NOS Install.

Dan

[sachabarac]

just a quicky the rx7 on f&f has been spotted at various shows and from what i hear it doesnt have nos fitted to it at all maybe someone can confirm ?

[Glenn Butcher]

Hi Sacha,

I'm sure if it did have NOS fitted, it wouldn't be done right anyway :)

Not many people have got NOS on a turbo rotary to work well.