BMW M140i JB4 with Meth Kit

Posted by Simon Newman on

BMW M140i JB4 meth kit supplied and fitted by Bolt On Mods

The M140 JB4 alone can produce approx 410bhp with completely stock hardware, then with exhaust modifications such as a decat down pipe the M140i JB4 can make approx 430bhp. The B58 found in the M140i is a highly tunable engine, much improved over its predecessor the N55.

When tuning past 430bhp with the JB4, the B58 requires more fuel, more octane, and an improvement to the intake air temperatures. The answer to all three of these issues in the B58 BMS meth injection kit.  

Methanol injection, or Water meth injection is a method of spraying a high octane fuel into your intake tract. This method of injecting a liquid into your hot air intake tract causes the liquid to vaporise. This vaporisation, or changing state from a liquid to a gas requires a lot of energy which is taken from the charged air. Therefore by the time this charged air enters your intake manifold its temperature has reduced and in turn reduces chamber temperatures. 

Methanol is also by nature a high octane fuel which burns very cool, in comparison to petroleum based fuels such as petrol you find from a regular fuel station. Once the methanol reaches your chamber it will increase the overall mixtures effective octane rating.

By adding a fuel source it allows the car to maintain its AFR targets easier, with less reliance on the stock fuel system when pushing the power levels. A richer fuel mixture also has a cooling effect, reducing chamber temperatures even further. 

The combination of these 3 factors - lower air intake temperatures, increase mixture octane and increasing fuel volume all contribute in allowing you to run higher power levels and reducing the tendency of engine knock or pre-detonation.  

Please feel free to ask any questions you have about the B58 meth injection package deal