A 12mm 3/4 reach spark plug is far superior when dissipating heat. There is more surface area on a long reach spark plug to dissipate the heat. 12mm 3/4 spark plug also has much less chance of stripping the spark plug hole threads because the threads are 3/4 inch long instead of only 1/2 inch. 12mm spark plug holes are further away from the valve seats and reduce the chance of cracking from the spark plug to the valve. Stock combustion cambers have square corners around spark plug hole. Having a sharp corner creates more heat from the plug to the valve seat and increase the chance of cracking. True performance heads have the spark plug hole that is smooth and contoured to reduce hot spot. I could sell you a cylinder head with stock chambers and big valves but it would be doing you a disservice. Technology has changed and a smaller long reach plug has always been the racers choice. Stock original cylinder heads only come with 35×32 valves. These cylinder heads come larger 40mm x 35mm valves for increase performance. The combustion chambers have redesigned for increased efficiency. They are machined for (90.5mm or 92mm pistons) 1776cc or 1835cc engines. I will make you a package deal. Make sure all of your auctions have ended prior to checking out. No COD, FPO, APO or PO Boxes. Sorry, NO US POSTAL service on heavy or large domestic orders. All items are completely insured. We are located in Southern California. 15 minutes away from Disneyland. Kustom 1 Warehouse, Santa Fe Springs, Ca. 7148159661 support and tech line. We carry 1000’s for parts. If you don’t see what your are looking for, give us a call. It is a small sample of what we carry. Track Page Views With. Auctiva’s FREE Counter. The item “2 New 1600 Dual Port Cylinder Heads for VW Volkswagen 90.5/92 bore 40×35 Valves” is in sale since Sunday, April 14, 2019. This item is in the category “eBay Motors\Parts & Accessories\Car & Truck Parts\Engines & Components\Cylinder Heads & Parts”. The seller is “kustom1warehouse” and is located in Santa Fe Springs, California. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, South africa, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Israel, Mexico, New Zealand, Philippines, Singapore, Switzerland, Norway, Saudi arabia, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Brazil, Chile, Colombia, Costa rica, Panama, Trinidad and tobago, Guatemala, Honduras, Jamaica, Barbados, Bangladesh, Bermuda, Brunei darussalam, Bolivia, Ecuador, Egypt, French guiana, Guernsey, Gibraltar, Guadeloupe, Iceland, Jersey, Jordan, Cambodia, Cayman islands, Liechtenstein, Sri lanka, Luxembourg, Monaco, Macao, Martinique, Maldives, Nicaragua, Oman, Peru, Pakistan, Paraguay, Reunion, Viet nam, Uruguay, Ukraine.

• Interchange Part Number: 04410135592DualHighRevSprings
• Manufacturer Part Number: 04110135592DualHighRevSprings
• Brand: china
• Warranty: Yes
• Country of Manufacture: China