Big Bore Frequently Asked Questions
A: No, kits ranging from 1352-1484cc will bolt right on. The 1621cc kit requires the cylinder heads and crankcase to be machined for the larger bore.
A: The big bore kits are direct replacement parts, designed to bolt-on to existing engines. No modifications or changes to the engine is required up to 1484cc.
A: No, the machined cylinders and light weight forged pistons will in fact save you 1052grams (~2lbs) Stock cylinders are 956gr each, the BB cylinders are 733gr, pistons are 463gr vs 423gr.
A: Well, in general making more power results in more heat, but being able to dispatch more heat by the increased cooling surface and the design of the cylinders, we normally don’t see that the engines run any warmer after installing the big bore kits. In some occasions, we see the exact opposite.
A: No, the kit has the exact same outer dimensions as the stock cylinders.
A: Yes, in fact out big bore cylinders are precision CNC machined from billet blanks of space grade aluminum, then bead blasted for increased surface area and a nice satin finish, then plated with Nikasil (Nickel, Silicone, Carbide) just like the OEM cast cylinders, and finished off by diamond honing to perfection. The nikasil allows us to run extremely tight piston to cylinder clearances, reducing wear, and ensuring excellent heat dispatch from piston to cylinder.
A: Yes, it is true that other brand big bore kits does not incorporate O-ring sealing properties. Our big bore kits are machined and fitted with O-rings using the same OEM 87x2mm O-rings for ease, availability and reliability.
A: Well, most other brands including our early kits had excessive oil burning in some cases. We have spent tremendous amounts of time, labor, testing and money into development and optimizing of the kits to have them to perform flawless. Some early kits had to small piston ring end gaps, resulting in ring butting, oil scraping, excessive ring wear and in some cases failure. Our kits have special wide profile and high-tension rings ensuring proper cylinder wall seals, and minimal blow by. It is however, normal that the high-density forged pistons can result in increased oil consumption, but not to the extent where it becomes a problem or a big hassle. The reason for this is that the high density forged pistons and special piston rings will expand more than cast pistons and cast rings like the OEM when warm, resulting in increased oil burn and blow by prior to the pistons and rings getting up to operating temperature.
A: No, not at all. However, adding one will give you even more power, and better mid-range torque.