The second paragraph I posted in the wrong thread! I've seen McBoney started a few threads on the same restoration topic, lots of replies from you KB there and here from him, so I got all mixed up! I am going to copy and paste in the correct thread.
Your workshop really is the stuff of dreams for the likes of me, Kawboy.
i notice the 928 is up in the air. Are you working on it ? Is it a manual transmission, just out of interest?
As for your KZ1300, was it a runner when you bought it? I wondered if you actually rode it before starting work on your project.
Yup, the 1985 928 Porsche just happens to be a 5 speed manual. Only 10% of the 928's were ordered in the manual gearbox. this was Porsche's attempt at busting in to the executive on the road vehicle. It runs but I need to pull the intake manifold to get at all of the emission vacuum hoses and replace. There's about 20 1/8" vacuum hoses that lay in the vee of the block. Hotter than hell in there and the hoses get cooked. One has to remember that back in 1985 silicone hoses were not available at that time. Maybe what they should have done was run stainless tubing down below and then rubber once out of the vee of the block. The reason that they all connect to the intake system down there is that's where the throttle body is in the very bottom of the vee. Quite the convoluted intake layout.
The KZ was a non runner when I got my hands on it. So no, I haven't rode it yet and being a fuss pot, I'd rather get it the way I want it rather than rush through the build. My big hold up is the cams. I need them ground, but ground properly. I have yet to find a shop with profiles for the grind that i want. Being a nuclear machinist and also a pipe fitter welder, and I guess I should throw in there, a Supervisor over 10 nuclear engineers at one point, my understanding of engineering and in this case machining causes me to ask questions to which anyone in the camshaft grinding business should be able to answer but can't. The ones that can like Crane or Comp cams can't be bothered with one off grinds so I'm hooped as far as getting them done for me. So I'm building my own cam grinding set up to do it. Biggest problem is life just gets in the way of me spending time in the garage. I'm close, but not quite there yet.
So the latest-
I've tried 3 different versions of a grinding set up to grind my own camshafts and the results I've not been happy with so next
Tried talking to several camshaft shops all over the US and Canada. Megacycle could do it and also Colt Cams in BC Canada also have master profiles to do it. Both want around $500 to grind a set of cams. and let's not forget this was to overcome deep valve seats that a machine shop cut for me too deep. And then there was the camshaft grinder in Toronto Ontario who ground a set of camshafts so bad that the base circle of the cam was cut below the cast material of the camshaft and the only follower that could ride on that base circle surface would be a roller lifter. IDIOTS !! Anyway, any work to be done on the cams was going to cost $500.
If I have to spend $500 to "fix the problem" I might as well get new seats put in the head and have the seats cut so that I can use 2.90 - 3.00 shims and have a virtually new head.
I talked to Competition Engines in Markham Ontario and they could do the seats for $500. They have a Kwik-Way valve guide and seat machine and the expertise to do it so I kept that in mind. I went back to Peterborough Automotive who are the people that did the original valve seat refacing but too deep and discussed the problem with them. They can also replace the seats and they have a far superior guide seat machine Sunnen PGM1500 and also the expertise to do it right. What happened when they refaced the old seats was the seats were too far gone with pitting and the shims were down to 2.20mm before they even started. I should have caught this before I sent them the head. Bottom line- the original seat refacing was $200. Replacing the seats this time, $30 per hole labor and $11 per seat. $491 total.
In a previous life I did valve seat replacement using a tig torch to lay a bead on the inside of the seat which sucks the diameter inwards and the seat will drop out. So for shits and giggles I got the tig torch out and had a go at one of the seats. First time around a little scary. Popping and sputtering, porosity, just ugly. After a second pass things settled down and the seat material formed a bead so I guess the seat was contaminated with oil and carbon which must have burned off.
Here's a couple of pics of what a seat looks like after laying a bead and popping it out of the recess in the head. And for the record, the recess is as clean as a fresh cut recess.i could just warm up the head and drop in a new seat.
The intake seat insert I pulled out yesterday - the counter bore in the head measures 1.440" x .375" deep and the insert bore is 1.140" dia. The .375" thickness is a bit of a problem since most of the 1.437 inserts on the market range from 1/4" thick to .340" thick. I did find one insert at 1.4445" x .375" by Serdi but have no idea what material they are made from. SB international will make custom inserts in any of their materials. I'd like to go the route of high nickel. I'll be pulling out and exhaust insert today and get some measurements for it then go shopping.