Loving the advice & experiences! Keep it coming. I figured there would be a few nitrous junkies on here
If you use it much, you'll be filling up your bottle on a regular basis. I've use nitrous before, with various V-8's, and it great for at the track, but not really that useful for getting to work in the morning. I'd go with a turbo if it were me.
I totally get this part, it would be just a fun thing. I want to take my 4Runner out to the local 1/4 mile track on the truck nights sometime in the next year or so when I'm done building out this engine. The power level I'm at is more than adequate for zipping around town, I hardly ever go WOT since that's a bit quick for me so would definitely just be an occasional thing. I'm hoping though with just a 35 or 50 shot a bottle will last a long time.
now dont get me wrong, i like where your head is at... I just have an @$$hole in the back of my head that always wants a little more once i get going with go-fast parts. little more boost, it'll be fine, etc.
that usually ends badly which is why i've embraced the slow with the 4runner.
i feel like if you just have it solenoided to an rpm range you're going to be blowing through nitrous really fast unless you only have it on at certain times.
IF (and that's a big if) it all works, it will be based on RPM as well as the TPS signal so it will rarely kick in. My methanol controller kicks on just at a simple 6 PSI but the nitrous would only turn on near WOT and only over 3000 RPM. The way the supercharger behaves on my engine I actually rarely drive over 3000 RPM. The transmission is always fighting me to drive at low RPMs which can cause problems.
I've swapped engines once before so heck, let's do it again! That's sarcasm by the way... I do like my current engine.
I had nitrous on a stand up jet ski. NOS wet kit with a fogger into the intake manifold and had a momentary setup so it came on at full throttle and then an easy to reach arming switch. Even with that I have limited experience at best. As usual tuning is everything and you'll be safe. There's lots of varying opinions I found for a wet system of fuel/N2O ratio. Originally I did 1:1 which was way too rich and then backed off the fuel quite a bit. In retrospect that should be pretty easy to figure out (but I was 16 at the time), I would assume you inject at 14.7:1 (or a hair richer) fuel/O2 and then some molar math to figure out how much nitrous you actually need to yield that oxygen ratio.
I never preheated the bottle or purged the system. I'm sure that's important but I didn't notice any issues with the short bursts I did. It always had plenty of pressure and the split second of air/fuel injection wasn't a big enough deal before the nitrous purged the lines and flowed out.
I would go with a wet system just since you aren't dependent on the injectors flowing enough to keep up, or get confused by the nitrous flow (though you have an AEM so maybe that's not an issue). I'd tap into the throttle body, probably inject off the back side of it. Then your normal fuel/air telemetry and mechanics aren't at all affected by the nitrous shot so as far as the engine is concerned everything is running normal and you're just adding on top of it without it knowing. Just make sure it doesn't ping and is tuned well and you'll be fine. But take everything I said with a grain of salt, I have limited experience at best and it was in a carbureted 2 stroke running race gas lol
This is super helpful! I agree, I've already got my AFR's dialed in really nice and I've got the octane boost to use it safely. A wet system that keeps the AFR's basically as is would work best since I don't want to keep the top end permanently enriched, so that if the nitrous isn't armed I would run pig rich.
I need to look into if a purge is worth my time or not. Seems more complicated.
I've installed some dry,direct-port,and single fogger systems; never on a 4Runner though. Actually still have lines, bottles and electronics lying around LOL
Is Mad Maxx running a single fogger or direct port, because I'm curious if it's a single fogger are there issues with uneven distribution to the cylinders. If you can have a separate fuel table for nitrous with the AEM I'd just use a single dry nozzle with fuel delivery through the injectors, as opposed to the mechanical means a traditional dry nitrous system does by increasing fuel pressure.
He's got a fogger, you can see some photos here:
Nitrous - Toyota Tacoma Forum. He's got it setup as a 2-stage system so it doesn't hit too hard.
I do have the ability to have two fuel maps that are activated by a switch but I'm worried that I would forget to switch the maps before using the nitrous and run crazy lean and do something I would regret. Unless there's a way to tie in the arming switch to the AEM fuel map switch at the same time? A wet system seems so much safer though in case it doesn't work right. It only has to fail once... I have an oversized fuel pump that's got plenty of headroom so adding the extra wet injector should not screw with my fuel pressure.
I have enjoyed building up my engine since I bought it with a supercharger 5 years ago. I think it can be summed up in 2 main points:
