Guys, I am quoting from a parallel running forum (by Shaan)
https://www.pakwheels.com/forumreply_az_TopicID!16937~ForumID!1~pw.html
Text is here.... what do you say to this?
(by Shaan)
my cousin has a toyota corolla 86 with 24 valve full throttle 1600cc engine with cng kit having emulator,enhancer, advance.The car can beat most of the modified vehicles but after usage of the car on cng for 1 1/2 month the acceleration power reduced. the car was fully checked and mechanically-electronically was found to be fine but when we repeated the engine compression test which was done back when engine was installed, the car compression had reduced by 30%,on inquiring from toyota he answered that it will further reduce to 50% in 6 months time and then will remain constant.if we need more power than get the engine overhauled or we can use it as it is for another 1 year.
furthermore the original engine of the car was overhauled 3 times in 2 1/2 years
The emulator in car just gives the vehicle computer(ECM) false impression of running on petrol so that car can run easily on low feul source it does not give any specail turbo power to engine as efi car have feul encoders installed in them so as they can adopt to the feul source used.
the advancer and enhancer advances the car timing and increases plug`s spark as high level of spark is required to ignite cng.This process increases engine temperature plus cng burns at a high temperature thus resulting in engine damage and high engine temp thus inturn giving rise to new issue of engine fans running constantly leading to increased feul consumption
The engine if seen during overhaul one can find black deposits on the cylinder block and pistons as if a torch flame has been burning in engine whereas petrol engine has just mild oil deposits mainly yellowish in colour. Thus cng run vehicle requires complete overhaul whereas petrol car saves by mainly not requiring bore and piston replacement thus cng run vehicle will require engine block replacemet after few overhauls as compared to petrol
People say cng(dry fuel) is better for vehicle,i would say lets explain this to the dumb guys in japan who have developed engine and technology like vvti,efi,twincam,v8 ,v6,super charged turbo etc that the engine they developed has special capabilities. (they have quoted themselves that petrol provides power to pistons and lubrication)
