After 3 months of looking for a head I have managed to get one for the Scirocco,Was going to get the shead to do it but funds have taken a turn for the worst(lost my job) so I am attempting a head job myself,I will follow this and add any pics and info I can...
Oh bad luck on the job front roccodan... Good luck with the head though. I'm gunna do one for a friends MK2 GTi over the coming months ready for a 2ltr transplant when the weather warms up (so he can take the car off the road and use his Bandit for work), I'll put some pics up as well when i get started. Any more news on yours wildwilliebaret ?
rough grind Well here`s todays effort before and after,maybe I went a little mad with the grinder on the bosses
What are you using to grind ? Dremel-like stuff or... ? (because i can't seem to find any longer cutters / sanding drums for that, to really reach down into the ports...)
I am using standard grinding stones from B+Q in my battery drill and got some aluminium tube also from B+Q that fits over the shank of the grinding stones and gluing the tube(about 4" long) over the shank with super glue. I will post some piccys up of said stone with long shank later. *EDIT* I found some Bosh steel cutting dies, 5 in a pack for a fiver in B+Q much better than stones as they don`t clog and cut REALLY well.
Nothing wrong with that. Be careful with using stones, if they get heavely clogged they can explode... honest.
Did'nt realise this thread had run so far! I was also given the tip of opening out the diameter of the exhaust valve seat rather than going to the cost of changing them and the exhaust valve for the bigger ones. The seats are tough rather than hard so you will need your carbide burs or your stones on this area. Dont think you have alot to play with before you reduce the wall thickness to much and risk dropping a seat while the engine changes temp!!! Not got a spare seat to measure this cross section. Mine measure up at 27.5mm and look like they would take going out to 28mm easilly enough. Anybody have a standard 8V exhaust seat they can measure? Cheers Domma.............
Roccodan, Mine is a MK1 DX head ! Don't know if there is a difference with a "PB" head? Whats yours? Cheers Domma........
Well, I have kinda hit a stop,There is a company near me that can cut and re-seat 35mm ex valves for me pretty cheap (10ea) so I can`t decide to go for it or not,I need to find out how much I can get new valves and seats for,as I am a bit strapped for cash at the moment,and don`t want to regreat not going 35mm now and having to strip it all down again in 6 months to do the 35mm and buy a new cam etc......
Just to show how bad the shourding is on VW heads...Also note the lip around the chamber. Valve at 1.5mm lift,with shrouding, with a torch in the port to help see the lift gap. De shrouded valve,again at 1.5mm lift That really shows the gains that de-shrouding can give at low valve lift.
When you say deshroud the valves , do you mean the part of the head around the valve seat , or do you mean a reprofile of the valve itself? 'Cos looking at DX valves , they're a crap design compared to others I've worked on , like FIAT twincams , Opels etc , wonder what gains are to be gotten by thinning out the base of the valve stem? and making the radius smaller from the stem to seat?
Think there are a few of us at this stage with the 35mm choice! Barkstar had alist of prices for seats and valves on a previous thread. Sounds like it could be a group buy. Roccodan, 10 a seat sounds pretty damn good. I was pleased to see in your pic's of the bosses that you can get away with removing that much material. A couple of my bosses have hair line cracks about 3mm deep but by the look of it i can just grind them away. Are you going to be running shorter valve guides to gain flow in this are? Sounds benefitial but heard the life of the guide suffers, makes sense but don't know how many thousand miles you would be likley to loose. For those doing this and getting knacked fingers trying to do the smoothing after grinding, you can make your own long reach flap wheels by hack sawing a slot down the end of a 10mm or so diameter metal bar or stiff plastic. ( Make it as long as you need to reach) Slide a lenght of emery cloth about two, three inches across the slot and wrap the start around the bar. These spin up well in the drill on course/medium grit for the initial smoothing. Cheers Domma........
