Does anyone have any experience running nitrous here?
On the surface it looks straight forward, with pitfalls being similar to oldschool “boost T’s” on turbo cars, where people getting greedy with the power or not giving it the respect it needs. Negate some of those and you have some extra HP at the push of a button/WOT/however you have it wired up. Again Nitrous has the same negative stigma as Boost T’s but both surely can work safely if kept within some parameters and actually thought out.
Thought pattern is to have a Wet Kit with fuel/nos jets for as low a shot as practical 20-30hp.
One of my presumptions is the intake manifold setup of the K3 should be better than a “log-style” manifold.
With a low weight of car to move it should be relatively effective…
Btw this is not some F&F type joke. I believe it can work, and am not too concerned about street or track/class legalities.
Extremely hard on engines. My very brief experience was putting a kit on cusomter’s Nissan Bluebird TRXX with an EJ20 and twin DCOE Webers back in 1988. Nitrous came on with a full throttle limit switch. Meagre improvement as measured by the doller spent. Was a waste of time as it was not reliable and finicky. Ended up putting in a FJ20 turbo import motor which quadrupled the power, was reliable and about the same price for that car combo at that time.
Give it a go, just beware of running lean (needs huge fuel boost as soon a you open the solenoid) and do you sums to see what it is going to cost. I repeat don’t let the costs runaway. Use forged pistons and super dupper polished piston tops and combustion chambers, or a clapped out engine you don’t mind destroying within a few runs.
It was a brilliant car. The guy imported a IRS rear end full cut from Japan and we pulled the live axle and grafted that in. Just over 300hp at the rear wheels back in 1990 and it was super reliable, spectacular to drive and as you say “a hoot”.
In the interest of discussion. Why would Nitrous be more damaging to the engine then say a Supercharger or Turbo Charger if they were all adding about the same amout of HP?
Lets say you had a stock k3-ve2, if you added a supercharger to add 30hp at the flywheel, a turbo charger that added 30 at the flywheel or a wet nitrous system that added 30hp. Would the nitrous system be more damaging for the engine and why? Aren’t they all artificially increasing the displacement of the engine in different ways (compressed air vs chemically).
Mostly to do with chemistry. Turbo and superchargers are effectively making a denser air charge, to which you add extra fuel. Nos is a violent combustion charge which needs much fuel added to cool and stop the piston from melting. The chemistry is hard to control. Normal combustion is not an explosion but a flame/burn. The speed of the flame during each combustion event needs to happen at the same rate.
Awesome info! Is there a way through tuning that Nitrous could be made to be more predictable/safe for the engine, or will it always need the mechanical changes you suggested above?
In a modern wet kit where, with correct Jet Sizing, you can target a proper AFR - the reaction is burning more fuel & oxygen. You have a charge air cooling effect with the injection (vaporisation/expansion) of the nitrous too. It’ll be a bigger bang, but a more violent/quicker one? You’re still burning 98ULP and Oxygen though?
Agreed in the wet system you turn your intake manifold ‘wet’ and not just dry with air…and then you may not have even distribution to each cylinder. However I believe our intake setup has a benefit here - that is the TB is basically in the middle of the 4 cylinders and we have curvey intake runners. This may offer better distribution than say a horizontal log type where the TB is on one end and the air/fuel/nos mix has to take a 90deg turn into each cylinder. You could well imagine the cylinder opposite the TB (furtherest from TB) getting either more or less of the mix…we might be better off. (We do have one 90deg from inlet piping past TB then into the intake manifold…presuming you put the Nitrous+fuel combo jet in a straight section of pipe prior to TB)
My thoughts over the last few days, for a Australia delivered K3-VE2:
Jets sized for modest 20-35hp ‘shot’
Need to retard timing. Well Aus delivered is already retarded compared to JDM for our fuel and likely so people could run 95 if they wanted without it blowing up. So if we run 98ULP perhaps the engine is already in a state of a few degrees retardation (Believe Mick advanced 5deg to gain some power on high octane fuel, or the leading theory is the JDM ECU advances timing to go from 75kw to 81kw)
Need to run colder plugs or ones with shorter electrode, to prevent heat build up. Easy Done.
Run all possible mitigation strategies: Bottle Warmer, Purge Kit, WOT Throttle position switch and RPM Window Switch, Wideband AFR Meter (or more expensive tuning on a dyno to more accurately set Jet Sizing).
Sure there’ll be variables, but there is with pump fuel aswell. So long as it isn’t tuned on the ragged edge, it should hold together for a while.
Though as Mr Gormsby said “clapped out engine” - well mines pretty smokey as it is, perhaps it needs a bit of block-ventilation
