Quite a while since an update. Is the car running? Hell no. So.. whats going on?
As I think I had previously pointed out. I had to replace the timing belt due to incorrect fitment by original engine builder. I also had to replace the valve stem seals (probably my fault on that one). I decided I'd remove the head to do this, so I could check a few other things whilst I was at it. So, off came the cylinder head.
Upon removing the cylinder head, I noticed a little nice crusty carbon build up on the inlet side of the intake valves. Interesting I thought, so I measured up the valve clearances. A few below spec. One had zero clearance. Theres our culprit.
I then removed the cams and buckets, placing the buckets into labelled bags (for anyone who is dissassembly your head, use some zip lock bags label them I1-I8 and E1-E8). Examining the cams I noticed a little scoring on some of the journals. On the head side, there was some engrained poo poo. I can only assume this was leftover blasting media. Another no no. If you are going to sand blast a head make sure you get all the media out (can be quite/very difficult). Otherwise, use soda blasting or similar so you can wash away the media with water. Scraped the poo poo out of the aluminium head with a razor blade and threw the cams in the lathe for a quick polish. Still a little scoring remaining, but no burr etc. It will be a non-issue, however, it shouldnt have occured in the first place. Upon removing the buckets I noticed they were all marked 40 (the same size). I don't know if the builder took a wild guess when building, or if he supposedly cut the seats the same height and tipped the valves such that he could just fit the same bucket throughout.
Whatever they did, it didn't work. I've got 6-8 buckets to replace to get things in spec, depending on how fussy I am. From memory, intake valve lash should measure 0.15-0.25mm on the 3sgte head, and exhaust should measure 0.2-0.3mm. This can be measured by using feeler gauges and rotating the camshaft until the low side of the lobe is above the bucket. Insert the feeler gauge between the bucket/shim and the camshaft.
I then went about removing the keepers/retainers and valve springs, and placing them in there relevant bag. The valve spring compressor I had was a complete piece of poo poo. I ended up using a bodgy method to remove the keepers and retainer. Rubber mallet, 25mm PVC conduit coupler with a magnet stuck inside it. It wasn't 100% successful and I wouldn't recommend using it. Until I got the knack of it, alot of the times only one of the keepers would come free, causing an uncomfortable situation of one keeper being jammed between the valve stem and retainer. I was in a rush to get it apart (god knows why, guess I just wanted to do it, NOW) and didn't wanna wait for the proper tool to come. I had ordered a bluepoint valve keeper removal and installation tool from the snap on man. I recommend anyone else to get this before bothering to disassemble your head. It'll save you alot of headaches. I had to take a baby file to the areas around the collet groove on the valve stems to deburr a few areas where the keepers had jammed. Before I could do this though, I had to drag said valve through the valve guide with said burr on the valve stem. Uggh. The snapon tool cost $67 + shipping, chicken feed. It'll also allow you to get to your valve stem seals with the head on the car. Reinstalls the keepers for you too. Part I ordered was GA317.
Anyway, got it all apart got the seals out after removing all the valves. I gave the valves a clean up on the face with a wire cleaning brush and a quick hit with the buffing wheels on my bench grinder had them looking pretty much as new. Noticed some minor inconsistences on the head face around the locating dowel positions. Obviously engine builder fumbled a bit lining the head up and put a few marks on the mating surface. I'm going to have the head resurfaced just to be double triply sure I wont have any surprises in the future. I doubt it'd cause a leak (it didn't before) but would rather pay ~$50 then be sorry later.
I also decided I would gasket match the exhaust ports. This was apparently done with the head work (apparently so was 'deshrouding the valves in the CC' - bullpoo poo). I've known since I got the motor that the exhaust ports weren't gasket matched but hadn't had the opportunity to do it up until now. Used a carbide burr on an die grinder to take the bulk of the material out. Followed by sanding drums and then hand sanding and polishing (only polish exhaust ports, its not considered good practice to polish inlet ports). Pretty painful process, not finished yet - my spare time is resonably limited. I also did EGR delete on this head (it is a USDM head). Turned up a bit of aluminium to be a TIGHT fit in the machined passage. Applied a little retaining compound and punched it in with a pin punch, ground the protruding part down inside the exhaust port. This should remove a little turbulence in that particular exhaust port. I don't think it'll go anywhere, but in hind sight, I probably would have turned up the length of aluminium longer, with a slight step on the end to fit in the tapped section of the hole (they fit a bung from factory to cover up the end of the hole in the head). Then would have tightened a bung down in the hole such that the pressed in aluminium piece couldn't move inwards or outwards.
Anyway, considering fitting even larger valves and higher lift camshafts, though am still undecided at this point. Have also toyed with getting a 2GR, but the amount of custom work (and associated costs) sort of scares me a bit. If I had a shiat load of cash, I'd certainly give it a go. A stock 2GR wouldn't satisfy me however.
Few pictures.
Scoring on cam pre-polish:
poo poo stuck in head:
EGR port hole w/ bung removed, aluminium pressed in there:
Started polishing port 3:
Port 4 - can barely make out where the aluminium rod was pressed in:
Naked head... covered in swarf:
