Has anyone fitted nitrous to a 1242 spi?

I've seen a kit in local paper which has been taken of a corsa, £175. Including the purge kit.

Opinions??

Slippy said:

Has anyone fitted nitrous to a 1242 spi?

I've seen a kit in local paper which has been taken of a corsa, £175. Including the purge kit.

Opinions??

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What size jets? You want to start low and build the power up.

25bhp - if i wanted more... how much are the jets??

Stick with 25 imo Rob from GSR is running that on his fine and I will be once I get it all set up

Jets are cheap IIRC - £10 quid ish in 25 bhp steps. IMO 50-75 bhp is the maximum on a road car, and you'd need a progressive controller to introduce the extra power steadily. You can get up to 300bhp jets

The supplier of any larger jets would probably want to ensure that the current setup is working fine before adding extra power to the system, to make sure that the engine, transmission etc. can handle it.

HTH

I wouldn't go over 25bhp.

Oldschool said:

I wouldn't go over 25bhp.

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Why?

the torque factor and the gearbox...

gearbox can take it i think (150bhp cinqs on std gearbox over in euro land)

its just the extra stress on all internals on engine i think that really limits the amount you can put in

I would tend to agree with Ghgost on this one. The clutch would give up before anything else on the transmission side first.

I may go and have a look at it - for that price i don't think i can go wrong.

JamesMK2 said:

the torque factor and the gearbox...

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Plus theres the fact that the 'boost pressure' that N2O creates will mean the combustion chambers are higher (max temp and temp at top of compression cycle), so theres always the possibility that you could start melting parts like pistons or valves!

Not big or clever....unless its a race car or custom built for that kind of power

If you read about nitrous on turbo cars - the temperature of the noz actually benefits the engine by cooling the chambers prior to combustion. It has a positive effect on the engine with respect temperature. With respect to stress, I agree, it is effectively with a 50bhp jet doubling the stress on every component of the engine.

Engines are cheap enough though.. really,, aren't they??

Slippy said:

If you read about nitrous on turbo cars - the temperature of the noz actually benefits the engine by cooling the chambers prior to combustion. It has a positive effect on the engine with respect temperature.

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...I was talking purely thermodynamically in terms of the effect of the pressure increase on the engine cycle...but the hot-cold cycle could lead to cracking if its too fast! (possibly anyway)....But turbo cars run higher than normal pressures anyway so usually use a reduced Compression Ratio to reduce the cycle temperatures!

And really high boost systems use water injection to cool cylinders too. But if using a turbo, why use N2O when you could just up the boost?

because in a turbo a 25 shot of the gas would give alot more than 25bhp, as it would take the temp of the charge down by 15-20 deg, so alot more air in + more fuel in much bigger bang :woot: :slayer:

what the nitros does is increase the detonation in the combustion chamber.the compression goes out of the roof and melts/holes pistons for breakfast.unless the engine as been rebuilt to withstand this,forget about it.it will lead to rapid engine wear.

I did say that it would be likely that the supplier of larger jets would probably want to ensure that the engine/transmission were capable of the extra power...............and the progressive controller would cut down on torque factor and the extra stress would be introduced gradually. I didn't mean a 'hard hit' kit like you see in the Fast and the Furious........nice and progressive I got an article on nitrousing somewhere..................I'll have to have a dig around..............

sumplug said:

what the nitros does is increase the detonation in the combustion chamber.the compression goes out of the roof and melts/holes pistons for breakfast.unless the engine as been rebuilt to withstand this,forget about it.it will lead to rapid engine wear.

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Wizard of NOS (amongst others), IIRC, said that an engine rebuild is not necessary to nitrous an engine, though they would have to look at the engine prior to selling a kit to ensure that everything would be OK, and they also must be satisfied that the engine can take larger jets if you so desire.

one word....insurance

surfin_fella said:

one word....insurance

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Good point

Some companies may not insure you, or tell you its for show/off road use only

"My car was looking a bit glum, so i've installed a system to inject laughing gas into it to try and cheer her up"

"awww, don't worry - we won't charge you more insurance for something like that "

haha, i wish.