I have a crx which came with the d15 motor, but currently its having a B16 motor.. its flywheel is lightened and, the a racing clutch is installed. the engine is producing a big shock when I release the clutch.

And I found that the part of the chassis where the engine mount is connected is cracked (because of the engine vibration?)

is this normal for all modified cars??

 

Dropping the clutch will wreck cars no doubt.

The big shock will be felt because of the broken mount, which would have been caused by dropping the clutch. It could happen in a stock car with a healthy clutch. You just need to not launch off every green light, or upgrade your mounts.

 

Engine mounts were broken And I replaced them. But still there is the big shock when I release the clutch. I drop the clutch fast only in some local drag races (not in day to day driving!)

A technician suggest me to replace the clutch with a normal one to avoid high engine vibration.

 

are you running a 6 puck clutch? those will destroy drivetrain mounts ......get a smooth engaging one if youre not running sc or turbo. i recommend exedy stage 1

 

My guess would be the car was railed on before, the rear main seal went out causing oil to get on the clutch disc and that is your problem.

 

Did you replace with OEM mounts? Perhaps you need something more solid.

 

but wouldnt solid mounts make his car "jerk" more as he was saying? Oem/mugen are the best to run. I'm still going with the oil on the clutch.

 

That doesn't sound like it's the case. I'm guessing it feels like such a harsh engagement because the mount is broken. That combined with a any "race" clutch will continue to cause problems and likely become worse. Reweld the mount and get a clutch that is more street friendly.

 

Ha true, or the op does not know how to drive a car with a "race" clutch meaning he's not feathering it. And broken mounts are really hard to do on the frame welds, maybe a hack job on your car?

 

Edit: Stiffer mounts will allow for less engine movement when the clutch engages.
Think "torque damper"

 

Jerk = / = vibration.