WHH has over 20 years of experience when it comes to engine modifications, in fact we were the first company to modify a gas string trimmer engine and coin the name "Pro-Mod" dating back to 1985. We have modified over- 10,000 engines! That's a lot of horsepower.



We offer our new G260 Zenoah's with two upgrades The original Pro-Mod, and the Pro-Race. We can also modify your Zenoah engine by simply sending it to us. All of our engine work is done by Tony Castronovo and Steve Arneson on WHH. We use only the best machine tools and there is no "hand-porting" so you can expect a quality and precise machine work. Don't let our low pricing fool you, we perform quality work, and in most cases, more of it . . for as little as 1/2 the price. We perform quality modifications at a fraction of the time it takes our competition. We have several dedicated machines to do specific tasks so we pass the savings to our customers.