[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]
On 22 Jun 2003 at 10:04, Aaron Clow wrote: > I already have a set of new (not > rebuilt) stock 1600 FI heads. Are my old heads better > to use than these? If so, why? I also have another set > of old 1600 FI heads that have cracks between the > spark plug hole and each valve. If these were to be > welded & cut, are they *still* better than new stock > heads or exchanges? In some cases it's important to keep in mind that the new parts you can buy today are not as good as the original parts were when they were new. There are many sources for heads. If yours are actually genuine, original VW type 3 heads, which are a matched set, then these would clearly be better than your old ones. Cracked ones should be approached with caution, but I've gotten away with some of those. I'd avoid ones with cracks to both valve seats. > Do cast iron cylinders warp at all with heat? If I scrape the rust & > gunk off these should I use these instead of a new set of 85.5 KS > cyls/pistons that I have or should I just use the new ones? They won't warp, but they can certainly wear. The rust on the outside won't hurt anything and the gunk will wash off. Those are just cosmetic. However, once the rings have worn the cylinders too much you have to replace them. > > You should also check the piston skirt clearance. > > What am I looking for with this? I'm keeping everything stock... You're measuring the difference between the ID of the cylinder and the OD of the piston. This gives you a way to measure the wear and decide whether you need to replace the parts. See your Bentley manual for details and specs. > I'm starting to get the notion that a lot of people clean/recondition > and re-use old parts instead of just replacing them (assuming they're > useable obviously). If that's most always a wise thing to do for heads, > case, etc., it's a notion I'm going to have to adjust to since with > everything else (non-VW) I'm usually thinking a new replacement is > usually better... Philosophies differ, but mine has always been that quality has to be judged independently of "newness." Sometimes new is better, sometimes not. Some placement parts are just awful quality. Parts sold for a 30 year old car may be poor quality simply because there's little demand for them and almost no incentive to make them better and lots of incentive to make them cheaper. For example, I almost always reuse OE intake valves, but I never reuse exhaust valves. I'm very careful to get good quality replacement exhaust valves, however. This is a good example of a part that you would never want to buy from JC Whitney. -- ******************************* Jim Adney, jadney@vwtype3.org Madison, Wisconsin, USA ******************************* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org