Who sprays 5th gear?

[carlos305]

Like the title says who here sprays 5th gear, i've heard mixed opinions on this some people say they do it and nothing happens others says the engine will blow. What do you do?

[carlos305]

what about first gear? Yes or No?

[urbanchaos]

i know nothing about nos but 1st is so short you hit the limiter in first and probably break something

[Nexx]

[twitch579]

Man I tell you its really hard not to, espicially when your side by side with another car thru 3rd and 4th and you know 5th is coming and u have to switch it off...and then get passed lol.


I do spray in fifth for about 3-5 seconds THATS IT. Sometimes if I have a top end run with someone thru fifth I will flick the arming switch on for a second or two just for a little speed boost.

[n2oHRZ]

Never done it, never will. I rather be safe than sorry.

[crash1555]

just curious whats the issue with spraying 5th?

[Nexx]

Originally Posted by crash1555

just curious whats the issue with spraying 5th?

gremlins yo, gremlins.

[Bwen]

5th and sixth are really long gears and are weaker? Not to mention if you arent winning thru 2-3-4 then you arent winning :0

[3hree5ive0ero]

Think about fast you go through gears from 1st to 4th and then how slow it is to go through 5th and 6th. Also, think about how constant your nitrous/fuel mixture is and how the rpm and selected gear is a variable.

When you spray in the lower gears, the nitrous/fuel mixture enters the cylinders with regular air to create a combustion. Note that because these gears go by relatively quickly, less of the nitrous/fuel mixture enters the cylinders throughout the rev range. In the up gears, because they go by slowly, you're forcing more of the nitrous/fuel mixture at a given time/rpm than you'd be at the same rpm in a lower gear.

That's how I always think of this, anyway.

[nissansource]

LOL if AF is fine your FINE!
no different then a V8 with a turbo 400 on the bottle
Done it plenty of times when racing a buds viper or a friends 650hp SRT4 on the freeway for giggles. this was on my old 350z in stock form

[3hree5ive0ero]

Unlike other forms of FI, nitrous is always constant. That is, turbos' and superchargers' spool rate depends on the engine speed, nitrous is independent. Because nitrous/fuel mixture sprays at a constant rate while the rate of the rpm increase depends on the gear, I'd assume this to be more detrimental in the long run for the engine.

I'm going with logic on this one.

[The Guy]

So when you guys are dyno tuning with nitrous you are spaying in 4th instead of 5th?

[3hree5ive0ero]

Originally Posted by The Guy

So when you guys are dyno tuning with nitrous you are spaying in 4th instead of 5th?

Don't we always tune in 4th?

[TTwinTTurbo]

I think I should throw this in. It might not be super relevant but about a month ago my buddy blew his motor spraying in fifth. I was in the car and we were racing an STI. He has a Dodge SRT-4. With all supporting mods and upped boost etc. He was running a 50 shot. About 130 maybe 140 A piece of number two piston broke off. 5th gear in an srt is the last gear which in a z is not but I figured i'd throw this is in because it was scary **** when that motor blew. he's getting it rebuilt to handle more boost.

[nissansource]

Everyones car and setup is different you cant justify others situations for others. Same goes for when turbo was first introduced to the vq35 platform people blew motors left and right from not being fully knowledgable about how the ecu and the car runs and idiot shops not knowing donkey about the platform or not knowing cars in general. aka: just mechanics throwing n20 or turbos on cars thinking its just supposed to work because its a kit. I remember doing the full turbonetics kit and would hear people have detonation including mine midrange. There is more finess to a car then just bolt on and go

[3hree5ive0ero]

Again, turbos/supers aren't the same as nitrous. They blew up because of improper tuning. Nitrous blows up due to lean conditions (bad/no tune) or because the engine consumes too much in a given amount of time than it's supposed to (which leads to lean conditions). That's why it's bad to spray in 5th. Stop comparing apples to oranges.

[nissansource]

Agree partialy w: turbos/supers/n2o, but both can blow due to lean conditions. sooo your saying i cant run a vq in a boat with no gearing and spray? your telling me i cant spray the whole way? lol. What does gearing have to do with anything? you talking prolonged exposure to increase hp? same goes for any increase in HP. I guess its time to tell my turbo guys that 5 gear boosting is a no no? Nitrous is already activated and motor rpm is already matched rotating speed so to continue a spray has no ill effect hell spray in 6th gear too stay in it to win it. Sorry as with any power adder on a stock engine let it be turbo,n2o,supercharged app you always run the risk on a non forged engine and it can be due to numerous things in the motor besides pistons,rings,rods,bearings. Oh even built to the hilt

[3hree5ive0ero]

Originally Posted by nissansource

Agree partialy but both can blow due to lean conditions.

I don't think you realize the difference between them. There's two different types of "lean" condition for nitrous. One of them is the same as turbo/super lean conditions where the AFR is off. This type of lean condition is due to improper tuning or lack of a tune. Second type of lean condition is too much spray mixture (turbos/supers don't experience this as they're not RPM dependent) per engine rotation. This is why you don't spray in 5th.

This is my 3rd post describing the same damn thing. If you still don't understand it, I suggest you stop posting and read it over and over until you do. Turbos and supers are consistent in their spool time as they're powered by the exhaust gas or driven by a belt. Nitrous is either on or off.

[nissansource]

What do you not understand about a mixture ratio??????????? its the same regardless, read up on the scientific properties of nitrous before you start educating forum members incorrectly.