Line bore cam tunnel in 1UZ head

[chuckles34]

I need an address for an engine shop in Adelaide who can line bore cam tunnels in a ! UZ head
Also need identity of a High Volume oil pump for the 1UZ

Thanks

[dnegative]

You cant line bore it........
Do you mean line honed? If a cam has bitten hard the head is economically fucked.

[chuckles34]

Cant the cam bearing surface be resized like a conrod by machining the mating face and then reboring it to suit? The aluminium would pick up on a hone surely?

[stidnam]

It can be done as you describe but is not cheap. I priced up a 4 cyclinder head here in Sydney and the rough quote sight unseen was about $300 - 400. I would expect that you can pick up a replacement 1UZ head for cheaper than that? Shims would also need to be redone as you are lowering the cam slightly and the timing is affected which may need adjustable cam gears to compenstate.

Easier to get a replacement head but if you can get it done cheap enough then go for it

[allencr]

Racing engine or you just want it to run & last a year?
If the cam is feed oil in front & feeds through to the other caps, then the front cap is the only really important one for oil clearance purposes & timing pully load on it. The rest of the head doesn't have any real load and the other caps are relatively unimportant as long as they are smooth & shimmed to line up with the front & can be cut on a lathe.
How bad is it? Cam binds & doesn't turn, scored up caps & head.

[dnegative]

They don't run bearings on the cam journals so whatever you take out of the tunnel is just going to be excess clearance.
They dont really hone well but I've been told you can clean them up.

[beerhead]

There shouldn't be any excess clearances if they shave the bearing cap a mm or so before they tunnel bore, which is fairly standard practice.

[JustenGT8]

Get a quote, I'll sell you heads cheaper than quote

[dnegative]

There shouldn't be any excess clearances if they shave the bearing cap a mm or so before they tunnel bore, which is fairly standard practice.

Yeah but you can probably buy an entire motor by the time you do that;

[beerhead]

He asks for a High volume oil pump and a tunnel bore and you don't figure he has head work that's worth more than $300 machining?

FWI:
If you have billet cams you can fix a ruined bearing by under-sizing the bearing surfaces of the cam and shaving the cap and mounting face and tunnel boring.
If you're removing the head don't ever waste your money on shims, a machine shop will have a valve head grinder and dummy fit the valves without valve springs and shorten the heads till the tolerances come true.

RE Oil pump:
I've heard very good things about porting oil relief valves to stop oil pressure spikes and inadequate oil drains in a head becoming an issue. Also have a look into head oil pressure restrictors on BMW engines, It's the only difference between M and standard blocks in the BMW range, just a tap in brass insert with a small hole to stop excess oil flow to the cams.


Now anyone out there know a reliable machine shop down south with the gear to help this dude, I only know where this is done in QLD.

[allencr]

There shouldn't be any excess clearances if they shave the bearing cap a mm or so before they tunnel bore, which is fairly standard practice.

Right, there won't be, except for the timing belt/chain ,especially if the head and/or deck are machined, and the valve stems have enough meat before the shim-over-follower hits the retainer so it's still within the OEM range of shims.

[JustenGT8]

Any work that is going to result in changed cam timing sounds shit to me? Especially with the expense of timing gears for UZ because of the naff way the cam are driven.

If the head is worth that much to save the other alternative I used years ago on an 18RG head was line bore well oversize a d machine in some bearing caps into the cam journals. BERCO here in Canberra did the work and that engine turned 8000rpm for years no worries.

[dnegative]

Right, there won't be, except for the timing belt/chain ,especially if the head and/or deck are machined, and the valve stems have enough meat before the shim-over-follower hits the retainer so it's still within the OEM range of shims.

Don't forget that the cam seal goes into the first cap, knock some off that and your probably going to have to make an entirely new cap to suit.