Hi,
auf meine Anfrage bei JJHooper ( Tip von Achim)nach MTC/ Wiseco Kolben habe ich folgenden interessanten Anhang, wie ich meine, erhalten.
The difference between Wiseco and MTC piston kits
There are a few significant differences between Wiseco and MTC pistons. Both are high quality forged aluminum pistons.
The most significant difference between the two piston kits is the Teflon wrist pin buttons in the MTC kit. The Teflon buttons replace the circlips to keep the wrist pin centered in the piston. If a circlip comes out while the motor is running, the damage to the piston and the cylinder wall is catastrophic. In addition, after the motor has run for a short time, the action of the wrist pin going back and forth in the bore and contacting the circlip will cause a shoulder to build up on the outside of the circlip groove in the wrist pin bore. This shoulder can make removing the wrist pin very difficult. That can lead to rod damage if you are not patient. (advantage MTC)
The second difference is in the length of the piston skirt. If this explanation comes with a picture, take a look at it. The pistons shown are 72mm (1075cc). The MTC piston is approximately one quarter of an inch longer than the Wiseco. This additional length adds greater stability in the bore. (advantage MTC)
The third difference is also obvious in the picture, it is the dome of the piston. The Wiseco piston is rated as a 10.25:1 compression ratio. The MTC is a 10.5:1 compression ratio. The factory compression ratio is 9:1. A factory piston has a small crowned dome. The Wiseco piston has a slightly larger crowned dome. The MTC piston has a significantly larger dome. I am not certain, but I doubt that the Wiseco piston is actually 10.25:1. In any event, the compression ratio of the MTC piston is significanty higher than the Wiseco. The compression ratio of the MTC piston works very well on a street motor. I own a 1974 Z1A that has had an MTC 1075 kit since 1990. It works well, it has plenty of low end throttle response and it does not run too hot. (advantage MTC)
The fourth difference in the kits is the MTC kit comes with a one piece copper head gasket, the Wiseco comes with a one piece fiber head gasket. The advantage of a copper head gasket is that it can be reused many, many times. You just have to heat it with a propane torch to anneal it, and it is ready to use again. If you remove the head with a fiber gasket installed, the gasket is almost always destroyed. (advantage MTC)
The Wiseco pistons are very pretty. (advantage Wiseco)
Da kann sich jeder selbst ein Urteil bilden