Whats up guys! As the title states I'd like to find out how much is safe nitrous? I was string really bored of my rx8 and decided to spice it up. Sent her tithe body shop and is getting a new paint job and wheels, but is always wanted a little more power, and not all the time being as I drive it at least 80miles a day. So I thought let me add some juice just to have a little fun. The motor is pretty fresh can't have more than 15000 miles on it and runs really good. I do my oil changes religiously every 2500 miles. Knowing theses little details how much can I spray?

 

search for your answer young skywalker

edit:

Here, I will help... start with this https://www.rx8club.com/series-i-major-horsepower-upgrades-93/nitrous-where-all-started-bhr-32578/

 

you are lucky that 100 shot of nos didnt blow the welds on the intake manifold

 

yea because then you would need the mad scientist to replace the piston rings you fried

 

you almost had me? you never had me, you never had your car

 

thanks ray. i was actually having some fun on a monday morning. he could have just read s no2 thread or two

 

i played nice at first and linked him to your thread lol

 

you gave him the answer with your first post so i figured a little f&f was needed

 

The question should be:

Are there any threads with up to date information that doesn't terminate in 2007- 2010 that touches on piggy back ECU/EMS?

Has anyone been able to finally tune an RX-8 with a COBB Accessport to retard ignition timing properly upon administering the N2O shot or is a piggy back needed?

Has anyone tried any of the piggyback solutions to achieve a higher shot than 55 - 75?

Searching through the threads seems to show this odd deadzone where it looks like people just stopped with Nitrous. Surely someone has a way of using a 100shot without blowing up the motor. I know the Renesis and 13b from the RX-7 have differences but to see RX-7s running 100 - 125hp shots without issue makes one wonder about the Renesis. Too bad there is VERY little info available and what is available is old.

 

iirc wcs had a mm cobb tune to spray 65 shot. i think ing was retarded 3 degrees. i could be wrong tho

 

I'm fully retarded
But yes the tune was 3 degrees retarded, ran like a champ.

Must be noted however that when I told Ray about what Jeff did with the tune, he sort of poo-poo'd it.

Can't remember exactly why.

But Lancifer is correct my setup ran me 3 deg retarded all the time, there was no trigger setup to retard the timing at the right time.

 

thanks for chiming in wcs. hope ya dont mind but you were the only guy i could think of that pulled timing

 

No problem

I will also add the reason why I stopped using nitrous.

First thing, the cheapest I could find Nitrous in my area cost 8~10 $/lb ... so basically a 100 dollars to fill a 10lb bottle.

Then nitrous became illegal to use on the streets in Ontario.
Then they got even crazier with laws that allowed the police to confiscate and crush your vehicle if they found street racing modifications. Aka Nitrous.

So I went boosted and now have twice as much power.
lol

 

Thanks for the info WCS.

Working on a nitrous build and my mechanic buddy was wondering the same thing. I had gotten a COBB before we decided to go Nitrous. I wanted a 100hp shot, he knows RX-7s can run 125 without issues but the timing on the RX-8 was more difficult to tune properly, the manifold can be ported and if needed we can do direct injection to try and bypass the N2O to one rotor thing (if that even works). None of us have used a piggyback EMS to try it out, was hoping someone has used a piggyback to get the timing right.

I'll continue searching and when we get to that bridge if it works I will let all interested parties know.

 

I think Ray had fabricated a custom direct injection solution.

With a big shot like that you'll need to watch out for pooling in the intake manifold, especially if you go with the traditional TB placement.

All the guys that ran nitrous here made it a practice not in spray before 4000~4500 rpm.

 

lancifer if you attempt a big shot you might want to have an extra uim and tb incase yours explodes. ask easy from bhr

 

 

Yep, that's what I heard. UIM grenade. Probably has a lot to do with the fused plastic joints.

 

We are going to start with a wet 55shot, as it needs no real ignition timing change to be fine. Then as we build up and add more to the car we will increase the shot. The 55 shot will probably remain until the rebuild w/ porting and more research and testing can be done with a piggyback to see if the ignition timing would work out. Then I will cross my fingers. 100hp shot won't happen for another year.. the 55 shot will happen this summer tho. Who knows, I may be satisfied with it and not move (unlikely LOLz).

edit: As much as I realize there is always a risk involved, I would rather get the research and testing done to the max before upping the shot. Although the cash to replace the motor/broken bits of metal left over, no one WANTS to spend that cash. :-) The end goal is to break 300whp without going turbo and without blowing something up.

 

the worst part of the recomened zex kit with a 55 shot is knowing you have 65 and 75 shot jets. lol

 

LOLz.... yeah I know.... I am going to be aching to get into the 75shot. But I am trying to calm myself.

There are a couple of piggyback units from Adaptronic that will retard the ignition on command and will probably be our first test subject on a test engine (don't ask LOLz).

 

IMO, the stock timing map is already far to advanced at WOT for almost any tuned car. The rich mixtures that the stock calibration calls for decrease laminar flame speed. Leading advance is set at 30 degrees to compensate, but with a leaner AFR best timing is not higher than 27 degrees.

In addition, there tends to be a plateau around MBT of around 5 degrees where power does not change substantially.

So, I would guess that if you set leading advance no higher than 24 deg at high load, you would give up little power NA, while giving a margin for NO2.

There are also a number of ways which might work to retard timing on demand with something simpler than a full piggyback.

 

Maybe a sensor? But wouldn't that too need a piggyback? Of course I don't for sure I am guessing, please do share info if so inclined.

What I am imagining is a manual control N2O delivery. When the contacts are touching the timing changes during the duration of the delivery and returning to normal when contact is broken. I'd drive the car daily and wouldn't really want to take a performance hit when driving sans N2O. The timing would only need to change when the N2O was hitting. If you have a simpler way to do it I am all ears, saving cash on not getting a piggyback only advances the project timeline. LOL

 

Subscribed. All of my previous cars have been nitrous fed. The limitations of a 55hp jet are....frustrating to say the least.

 

The simplest/cheapest thing that might work would be to bias the IAT or baro sensor.

Both are used to compensate for air density, which is sort of what you're changing with n2o. It might work to just have a dpdt switch that would pull the baro sensor out of the circuit, and drop in a small resistor that would give the ecu something under 4.7volts.

Then the ecu will calculate load as being higher than you would ever see in the real world. Not only could you set timing for that load, the ecu would try to fuel it. This could be adjust by changing the multiplier in the load max baro compensation table.