eman930

Hey This winter/spring I will be doing my Project red blaze, 1987 924S, I am going threw my engine for the second time, doing some more mods and stuff. I am almost 100% sure I will be adding a nitrous kit with approx 50-75hp shot, I have used nitrous on other cars before and I just love the stuff. Im sure the NA 2.5 will respond well. I have heard that some of the other rennlisters have used nitrous on there 944's before. I would love to go with a wet direct port system but Im not sure If I want to spend the money, So Im thinking more of a wet single jet fogger with a nitrous progressive controler, this way I can use it threw out most of the RPM band. Any input form other users would be great, Just want to see what you guys have for a setup and some results. Thanx

Jakerx

well if you want to tap your intake manifold go with direct port. if you ever plan on selling the car that would be a major detriment. i wouldn't suggest anything more than a 50 shot really, but then again i'm pretty conservative in my views on nitrous. you will definitely need a purge system and a window switch (activating and cutting off the nitrous flow at certain rpm bands). if you want to save money, get a used system. no reason to blow money on a new one unless you really have money to lose. most people on the list say nitrous is for ricers, and for the most part it's true, but a properly tuned system can do great wonders and can help a lot. i suggest a bottle no more than 5lbs for starters. tell us what you decide.

hosrom_951

Got juice?

Fishey

What year is your 924S? It makes a diffrence when it comes to running N20...

You can run a 75shot on a 87 or a 88 but since there is a compression diffrence you will need to do more on a 88 to get it to run safely. Also whatever you do make sure 100% that you use a window switch. These cars don't take to the juice to early so make sure you window it 3500rpm+ to 100rpm short of redline. Also remember you will need to go a stage colder plug on the 87 and on the 88 you will need stage colder plug and -1 degree timing after 3500rpm. Fogger system is fine just rememeber that its less effective and can be harsher on a car with poor flow distribution to the cylinders. However on the 924/944 the intake system is pretty good so you really dont need directport but its never a bad idea.

Campeck

dont you have to add more fuel to the mix since N2o is basically liquid oxygen(i think)?
wouldnt you run lean with "wet shot" with no extra fuel?

Uranium-235

N2O is not liquid oxygen, the molecule breaks down under heat and releases the oxygen and nitrogen. The oxygen is used to enhance combustion and I believe the nitrogen acts as a "coolant" to help keep combustion chamber temps down. What can happen is that too much N2O is used, and leans out the mix, causing overheating and melted pistons. However, on O2 sensor equipped cars, the fuel management system should be able to richen the mixture (within reason, of course) to accomodate the extra oxygen. Larger injectors become necessary with higher levels of nitrous, then you need to step up to stand alone fuel management. I think a 50 hp shot would be okay, though.

FSAEracer03

Haven't used nitrous, have you? Nitrogen doesn't act as a coolant, the N2O itself does. The molecules absorb compustion heat as they transfer from N20 to N2 and O2. Also, a lot more heat is absorbed if the bottle has a siphon and injects liquid N20, as the heat removed from the process as liquid forms into gas is high.

Also, you NEVER want to spray without compensating fuel, as Ashton was saying. If you rely on your O2 and ECU to comensate for you, you're in for a costly suprise in about 2-3 seconds.... that's how long it takes an ultra-rich nitrous state to burn a hole in a piston. It's even dangerous to have the comensation fuel lines longer than the nitrous lines, because the nitrous will hit first and cause a momentary lean.

This is not a toy, so good luck and be sure you set it up and use it correctly.

tomc_85.5_944

OK, never spraying without compensating fuel is only for the 944, is that what you are saying? I'd love to do this to mine as well, as if I smoke the motor it's a good bit cheaper than the one in the NSX....In the NSX, and motorcycles, you are OK with a small dry shot, but once you get above a certain hp, 40 in the zx-12, 100-150 in the X, roughly, it is recommended that you go with a wet shot. This is because in both the ECU senses a colder mixture, and adjusts the fuel accordingly. Is the 944 not like this? Serious, not being a smartass. I agree with the window switch idea, as it is a good safety measure. Anyone on the board with a good safe system, what was the cost?

eman930

Once agian Im really leaning toward a wet kit (nitrous and fuel) Not a dry kit (just nitrous). The Wet kit has fuel and N20 comming out of the fogger jet. I will Run a 10lb bottle and start with a 50hp shot, This will need a 2degree retard and 1 step colder in plugs. I have Run and tuned nitrous on both of my other cars a V6 Tacoma with a 75hp shot and a 86 VW jetta with a 50hp shot, so not saying Im a pro but I am no green horn. I direct port would be sweet but I think its a little over kill for such a small shot. Im thinking of using a MSD digitail 6 plus which has a nitrous retard setting. other then that it should go well, In the next couple of months I will post ome pics

tomc_85.5_944

GREAT. If you could do a DIY with a cost associated with everything, that would be even better. Lots of people have probably thought about it, but were/are too scared to post up for fear of retribution... I have never installed/ran N2O on anything yet, and am still trying to get educated on the safest way each vehicle works with what...

Good luck, and keep us posted!

FSAEracer03

I was saying don't spray without compensation fuel. The 944 is no exception. Be safe or have cash in hand...

Mike C.

Fast 924S, please let us know how you make out. I think N20 might not be a bad idea for us 944 NA owners who'd like an occasional 'squirt'. I guess the trick would be training yourself not to do it all of the time....

Fishey

With 2degree retard and 1 colder plug you would be good for 75shot..

eman930

NOS tuning guid says 2-4 degree for a 75hp shot and 2 steps colder, while the 50hp says 2 degree retard 93+ with 1 step colder, I believe