Nitrous install on 3SGE

Hey guys, a few weeks ago I picked up a cheap mr2 for a project, and I'd like to give an n2o install a go. Has many people on this forum given it a crack? How can you tune the afr without a dyno or aftermarket ecu?
It's a bone stock 3sge 1991 sw20. Hoping to run just a 50 shot, just for a little bit more kick when I need it.
Cheers guys

ranga97
Hey guys, a few weeks ago I picked up a cheap mr2 for a project, and I'd like to give an n2o install a go. Has many people on this forum given it a crack? How can you tune the afr without a dyno or aftermarket ecu?
It's a bone stock 3sge 1991 sw20. Hoping to run just a 50 shot, just for a little bit more kick when I need it.
Cheers guys

 
You need a dyno and aftermarket ecu to run it safely, otherwise there is a high chance you will cause a lot of detonation.

If you are 100% set on doing a Nos kit, spend the money once, do it right. 
 
Also be aware that Nos kits are extremely illegal in all states (as far as I am aware), and even having the system in the car but not hooked up is illegal. 
 
 

MCT_MR2
Best person to speak to on here about nitrous would probably be kameleon

 
Not knightrous?

ranga97

TonyMR2
50 shot hey, 50 days of fun.

So 25 only equals 25 days of fun?
 
Thanks for the replies, as for aftermarket ECU's... any recommendations for a low-end/midrange model?

Probably an older Autronic would run it ok.

Is this a street car?

I once upon a time researched nitrous for my 3sge, but the cost was just way too expensive. 
To be set up fully you're looking at:

-Kit with bottle warmer etc etc $600-700
-Aftermarket Computer $400
-Dyno Time $250+
-Wideband $250+

Plus any extras

Then there is filling the bottle itself. Local places in Brisbane charge $16.50/lb and a $15 fee.... so for a 10lb bottle it costs $180 to fill it up... and you wont get much time out of that. 

Not trying to shoot down your ideas, just keeping it real. A lot of people try for bulk power cheap. Unfortunately, this is generally not the case. Unless you're Johnny from WA.

have you looked into doing a turbo swap or selling the car to buy a turbo? This would be a more cost effective means long-term and you will net more than 50hp.
 

50 hp shot :) try take out your spare tyre, reduce your fuel down to 1/4 tank, empty all non essential shopping items In your boot, swap your battery to a light weight battery, and feel the effects better than a 50hp shot of nos.

If your mathemetatics is 3sge has 177 Bhp (flywheel) 7000 rpm and a 3sgte has 221 Bhp 6000 rpm, therefore about 50hp difference - it's not that simple and the turbo will still be faster.

Unifortunately 50hp nos is a long way off a 3sge being fast and very close to disaster and fines.

Sensible changes alternatives, change your intake cam to a later generation (cheap if you can find one) or aftermarket cam. There are limits on what you can put in based on your valve springs/shim style. Get adjustable cam gears, dyno tune (advancing timing), lighten the flywheel. Get the car light. More fun wherever you want, sustainable and legal. Cost you the same as the nos, but a lot of time on the tools.

Cheap fast is short lived. Laws of engines.

Eric
You can do the above as tony said, or put some good tires and coil overs on it and beat half the field out there. you dont need power to go around corners fast.
 
As an example, Adrian can do a 1.10 arround Wakefield park in his 3SGE SW20 (Approx 130whp). I could only manage a 1.16 with 250whp.

You would have been a lot faster with more practice. I managed low 1:16's with my Beams....

Nitrous posts, love em :) All this talk of N2O makes me want to try it on my BEAMS 
 
Back in the days of 28k internet speeds, racing down Prinny every Friday and Saturday nights and no online information on EFI nitrous setups i started playing around with nitrous systems on my first car with some bits my friends dad had sitting around from his drag bike. It was parts from a NOS branded kit.
 
We worked out what worked and what did not by a suck it and see method by testing and reading the spark plugs and soldering the jets back up and drilling them smaller/larger to suit. We didn't even have enough coin to buy jets so no wideband or aftermarket ECU was in my budget!
 
Starting with 25hp jets and plenty of fails with melting plugs and the like we ended with a 2 bottle/single fogger  setup with 200-250hp worth into an engine that made about 150hp from factory. Pretty impressive if you ask me. I wish i had photos, but this is pre phone cameras. They weren't even colour back then.
 
What MCT mentions about timing tuning is correct. My rule was take out 1 degree of base timing for every 25hp of Nitrous "jetting" (the power values they give are conservative in most cases). Anything over 75hp and i had to have much colder plugs (even gap them differently on the centre cylinders due to crappy centre feed design inlet manifold). The car drove quite rubbish off the bottle like this however.
 
These days N2O is very cheap and there are lots of different setups you can purchase with great online information to boot. You can easily do the same but i am not sure it would be worth it for what you appear to want to achieve with your car?
 
Don't forget refill costs and legality.
 
 
 
Not my car but:-
 

 
 
 

And I still say 2GR gives a ridiculous amount of power (read too much, S/C 2GR is totally nuts ((and can get engineering approval)).
 
Keep the authorities off your back by doing it the approved way. 
 
Supercars get approval for their uber power for being on the road, we can as well.