Off with the head I say!

and she's off!

http://imageshack.com/a/img34/638/uvb7.jpg

Now that it's apart, I need to check and clean everything and looking for the spot(s) where I'm losing coolant and compression, thus failing the sniffer inspection.
I'm not going to put back the A/C and power steering parts. This sure is a good time to swap in a manual rack.
Need to put in valve seals to control the oil burn. The pistons tops are caked up with it.
Need an O2 sensor. I want to put on the performance header that I've been storing in the garage.

Plus a lot of little tweaks and mods. Wish I could find some upgraded cams to swap in.
Not sure I can get everthing I want done before theend of this weekend.

How much can the head be shaved(per service manual)?

Wondering if there's significant power to pick up with some home porting on the heads?

Jay Johnson

The impact of home porting depends on how good you are at porting. There's some gain to be had. Cams won't help you much at all without a standalone ecu. Some folks use the exhintake can trick with success, but it can be done after the head is back in the car.

If you don't already have a manual rack, they are hard to find. Best bet is to do the depowered rack option, which is easy to find with a Google search.

I looked over the tri-y headers I had in my garage and the primarys had qute a bit of tubing sticking into the flange openings. Not good for flow.

So, I took some time and ported them out to help with the flow. Unfortunately, I was about halfway done before I thought to take some pics of unported header :(
You'll just have to trust me that the original was less than optimal, and quite obvious. In additional to the primary tubing blocking flow, there were also some of the flange welds that beaded up on inside of the tubing.

I ended up taking about 1/16th inch all around out of each primary(adding 1/8th inch to the port diameter, but cylinder 1 and 4 were had more interference in the airway. Those were cleared an additional 1/16th from the outward sidewall of the port. I only went deep 3/4 to 1 inch, just enough to give a transition form the flange port to the primary tubing.

Port 1 and 4 shows the tubing just short of the header flange mounting surface. While porting those, I was ablet o get the outer wall to contact the flang, just a little deep in the flange. I wish the manufacturer used more tubing length and then milled the flangemounting surface. These were the ports that interfered with the flow an extra amount, but I mitigated that issue pretty well.
Here's the header after porting.

http://imageshack.com/a/img853/4980/yc3f.jpg



http://imageshack.com/a/img14/9891/8am6.jpg

http://imageshack.com/a/img7/7042/u08l.jpg

I think it should be good for a bit of power gain.

Tomorrow I'm going to examine the heads for issues such as cracks, and see if there's some easy and quick porting work that should pick up some gains.

Jay Johnson

Well, I started to tear down and clean the cylinder head and I noticed a little scratch on it.

I took a closer look with a magnifying glass and it's a crack :(

http://imageshack.com/a/img703/7365/hnez.jpg

I don't want to repair it with aluminum welding. I'm thining that more cracks could develop on the head later.

Anyone got a 1.6 cylinder head in good runnable shape available?
I'm going to option going that route, before I commit to swapping to another longblock.

Jay Johnson