I came across a universal Wet type Nitrous Oxide System in a buddies garage, he is looking to sell it, its a set up for 4-6 cylinder single nozzle 35-100hp shot, all complete never installed......

has anybody used nitrous on a 103 engine? if so what kind of performance did you see?

Nitrous systems correspond to their given shot numbers (jet size is very important) as long as your fuel mixture is correct. Continuous injection systems, like yours, need a supplementary fuel supply in order to fill the needs of any amount of nitrous to avoid burning up your engine. Make sure you run a wet system and not a dry one. You can use a dry system only if you have a computer running an auxiliary injector (the ideal option) to keep the mixture in check. I'm sure you can run a 100 shot nitrous system on a stock M103 without breaking anything. Look at the condition of your engine first before throwing too much nitrous in it.
Adam

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Current Stable:
01 ML55 AMG
92 500E (a few mods)
87 300E (lots of mods)
00 Chevy 3500HD Diesel Box Truck
68 18' Donzi Marine
06 GT i-Drive7 1.0 Mountain Bike (with GPS!)

PREVIOUSLY OWNED:83 300SD, 87 420SEL, 88 420SEL, 90 420SEL, 86 560SEL, 86 190E 2.3-16V AMG, 94 E320

Oh, you should also use a RPM switch in order to cut your shot for shifts and especially mixture, your redline kills your fuel pump.

__________________
Current Stable:
01 ML55 AMG
92 500E (a few mods)
87 300E (lots of mods)
00 Chevy 3500HD Diesel Box Truck
68 18' Donzi Marine
06 GT i-Drive7 1.0 Mountain Bike (with GPS!)

PREVIOUSLY OWNED:83 300SD, 87 420SEL, 88 420SEL, 90 420SEL, 86 560SEL, 86 190E 2.3-16V AMG, 94 E320

I tried it on my '99 CLK 320. It's jetted for about 100hp. I like it, but there are a few drawbacks: Varying bottle pressure is a drag to deal with. Bottles run out faster than I expected and are expensive and time consuming to fill. You need to purge before you use it (purging and leakage is probably where ½ my juice goes). The computer will often refuse to shift into second while the juice is on.

Pluses are: I can smoke all my friends rides.

People always talk about how the power increase is day and night and their rides are super fast now etc. I figured with a my light car (3200lbs) and a 100 shot I’d be pretty happy, but in the back of my mind I knew that 315hp isn’t all that much. It is a nice increase, but it’s no hot rod. I think it’s about as quick as the 500 or 55AMG.
I have G-Tech accelerometer, I’ve only had a few chances to use it, but it’s about 5.3 seconds 0-60 with the nitrous, 6.0 without.