So, I'm thinking that I'll purchase a Fit and when I do, I think I'm also going to purchase a nitrous kit.

With all that money I save on gas, I can afford to get premium!

I'm planning on getting the auto-switch-on-by-RPM nitrous switch, which basically kicks in at 2500 RPMs while full throttle and keeps the nitrous valve open until 6200 RPMs so that it won't spray into redline-zone. So, I hit the "on" switch, open the valve on my bottle, and then when I put the pedal down I get boost!

I thought it was a cool concept, it was new to me, might not be to y'all.

But anyways, my question was: what size shot should I use?

I think I've read around here that the Fit puts down about 90 HP to the wheels. Correct me if I'm wrong, but the HP rating of nitrous(IE 25 shot, 30 shot, 35, 50 shot) are relative to the HP gain to the wheels...

So a 50 shot would put the Fit at 140hp which is less than the upper-stages of the SC/TC options(150-160, right?) that have been heavily discussed here, so I figure a 50 shot would be safe and reliable and wouldn't require any upgraded internals or pumps, right?

Could I do a 75 shot? Turbo/SC puts strain on the motor probably 80% of the time, but I'd only be spraying nitrous maybe 5% of my total driving time if that, so it wouldn't even wear as much as the 10psi from a turbo/SC, right?

lol, I hope I made sense.

 

if you plan to run nitrous for power, please don't get a fit. get a mustang and blow that up.

 

you realize that when properly used nitrous for power is just as safe as any other kind of FI?

on top of that, it's more than 6 times cheaper and yields MORE power than the supercharger that everyone on this forum reveres.

I ask: Why WOULDN'T you plan to run nitrous for power on a Fit?

 

I think to each is his/her own....meaning if you wanna run nitrous, so be it. If you have other plans for your car...kool. I respect anyone who does any upgrading to their Fit.
As far as your questions, nitrous shots usually go from 25, 50, 75, 100, 150 & 200. As far as power...instant to the wheels!! So it would be like gain 25WHP or 50WHP(wheel horse power).
If you removed everything from your car....backseats, spare, tools...had a fifty shot w/ I/H/E....IMAO will would beat a Scion TC.....Vtec FTW ...hope this helps.


tonyd3773 (video guru)

 

uhhhh does that seem a bit high....or is it just me

are you like racing ppl at every light or is this just to get by on the apparently all to mundane commute???

could just be me...but.... I grew up with nitrous=special occasions


KAaaaaaaPOOOOOWWWW, do the right foot in drunken stumble dance

 

lol, yeah, that was an exaguration. but you've nailed my point, nitrous is barely ever used

 

Reason being alot of people think it's a quick fix with alot of damaging side effects to your car.


tonyd3773 (video guru)

 

One thing to keep in mind is that the turbo and sc kits come with some kind of programming to alter the timing. With nitrous you'll be relying on the car to alter timing if knock is detected.

I'm ALL for nitrous (have had it in many cars) just don't get carried away...stick with small jets and run premium. You'll also have to consider going one step colder on the spark plugs. These little motors are very touchy when you're talking about adding 50% more power. You'll also have to watch the limits of the stock fuel pump...just giving you more things to consider.

 

I agree totally...you will either have to forward or retard your timing on the Fit. Not sure which way you need to go though!! To be honest....I wouldn't shoot more then a 50 on the stock car....just my 2 cents.


tonyd3773 (video guru)

 

yeah I honestly wasn't thinking about shooting more than 50, honestly the only time I ever see myself using it is maybe once a month at the track and every rare chance I might race one of my buddies

now, with the timing, if I have a professional racing-specific shop install the nitrous kit, they'll likely adjust the timing for me, won't they?

 

You would think a decent shop would!! Not really sure....if they specialize in Honda/Acura...I would think they would be able to help you!! I'm in for interest!!!!


tonyd3773 (Video Guru)

 

There's not an easy way to adjust the timing on a car with distributorless ignition. A shops ability to alter the timing depends on whether they can reprogram the factory ecu. In other words, not likely.

 

so what would I be looking for that would allow me/them to reprogram the factory ecu?

 

I'm new to the Honda thing, but I don't know if anyone has a way to reprogram the Fit yet. Hondata will likely be the first, but they don't have an ecu for us yet.

With Nissan's, the dealership can alter the base timing by a couple of degrees using their OBD2 software.

The factory ecu takes readings from the knock sensor and will retard timing when necessary. With premium fuel and a small nitrous jet (realistically over 30hp could be a problem) the factory ecu should be able to compensate.

I'm just trying to give you more things to think about. Nitrous is not as simple as it once was...for example, you will also need an activation switch that can read the throttle position because of the drive by wire. No simple microswitch anymore. Nitrous Express makes all the stuff you'll need, but it gets costly and isn't simple.

 

I guess I should have said that no one sells a programmer for the Fit yet. The turbo and supercharger kits that are available for the car all come with one kind or another of new program. They just aren't available for custom order with a stock, race, and nitrous program or anything like that.

It just means that you have to be more conservative with the amount of nitrous you shove through the poor little 1.5.

 

I talked to the guys at NX(thanks for the recommendation) and obviously their fly-by-wire kit is perfect for the fit, the guy said that it would be fine with a 35 shot all day long but that i should only shoot 50 at the track, also he said their window switch works perfect with the Fit, and didn't think I'd have any timing issues with a 35 or 50. Would you recommend I stick to a 35?

 

I'd reserve the 50 shot for "special" occasions. I know 50 sounds like a tiny kit (I've never run that little), but it's a 50% increase. That would be the same as putting a 150 shot on a new Mustang GT. Which is about the maximum recommended amount.

NX stuff is very well made. Their solenoids are some of the best. I've used their TPS and window switches and never had a problem. I prefer the NOS new style bottle valves. They have a port so that you can put a nitrous pressure gauge before the valve. That way you can check bottle pressure without even opening the valve. NX might have that now, but didn't used to. My knowledge is out of date.

For the 50 shot, I'd go one heat range colder on the plugs and make sure that the only fuel in the system is premium.

I've had nitrous on 4 cars now and have never had a single problem. Even when I was running a 225 kit with a Jacobs Nitrous Mastermind.

 

That's awesome. Do you think that running colder plugs normally would really affect the car that much? Also, I'm pretty sure I'll always run premium. And, one last thing, if I get I/H/E with the nitrous will the open-flow allow the nitrous to give me even MORE gain?

Correct me if I'm wrong, but the Fit is at 90 whp, so with no mods a 35 shot would give me 125hp(50 would do 140whp), but would that end up being maybe 135whp(35 shot) and 150whp(50 shot) with I/H/E?

 

just get a wet kit (one that sprays gas and nos) and you should be able to run at least 125 shot....espically if its just gonna be every now and then at the track. i mean just like you said, it should be alot better on the motor than all these sc combos that are out there.

just make sure and tell us the quick times that you run at the track/

 

Turbo???

Nitrous kits are usually rated at whp. So the 35 jets should be good for 125whp. Keep in mind that a nitrous car hits peak torque the second you hit the button. Given enough traction a nitrous car with equal peak hp is faster than a turbo or s/c car because of the torque gain.

An intake is not that important with nitrous because you are supplying your own oxygen to the motor through chemical means. The header and good exhaust will have huge gains just as it does with turbo or s/c.

Given a strong enough bottom end the ultimate combo is nitrous with a turbo. The nitrous helps the turbo spool faster and adds cold dense air. NHRA doesn't allow the combo likely because it's too good.