325 Head questions

Post Sat Jun 01, 2013 9:57 am

I've just picked up a 325 head, complete with both manifolds and TB. The head is of unknown heritage and it's looking pretty grubby. Also, two rockers have snapped off. So, I have some questions please:

1. What's the best way to clean up a dirty head? Get it acid dipped?
2. Can you still buy spare rockers and if so, how much?
3. Assuming it cleans up ok and I get the rockers replaced, pressure test and skim the head, what's it worth?

I'm in two minds whether to do it up to sell, or fit a better cam in and put it on my car. Had good gains from changing the cam on my old Tourer.

Post Sat Jun 01, 2013 10:14 am

Hi there Peter, sorry about yesterday

I was driving most of the day, put my phone on the seat, then my laptop on it, sorry again.

Anyway:

1. Personally, I soda blast my heads, but some places do acid dip them.
2. Rockers are about £14 each from GSF and ECP
3. Depends how far you go, valves recut, new stem oil seals, exhaust guides lined.............. Theres rebuilding a head, and rebuilding a head. If you are paying a machine shop to do the work you will make little money, for the effort. Selling it as pressure tested is probably the best for that.

If you are planning keeping your car long term, I would be keeping it as a spare, or rebuilding it properly swapping it and keeping your current as a spare.

Post Sat Jun 01, 2013 10:21 am

First thing to do is look for cracks between the cylinders. 325i heads are fragile things in that department so its worth checking before you spend a penny on it.

I don't think they're worth megabucks because there are still quite a few complete engines out there that don't sell for strong money. So unless you're fitting high-lift cams and wider valves then a rebuild won't turn a profit for you and it's better as a spare.

There's a rebuild guide for these heads in the Wiki:

http://www.e30zone.net/e30zonewiki/inde ... inder_Head

And you can still get the rockers and valves from BMW. Although they never made a tourer, as far as I'm aware

Post Sat Jun 01, 2013 10:35 am

I have spoken to zoner's who have paid £700+ to have a 885 head rebuilt by a machine shop.With rockers at £14 each(you may need up to 12 of the blighters)and a labour rate of £30ph for 8-10 hours work,it's easy to see how such a fiqure is reached.
So there's no profit in having someone rebuild for you to sell on,but a stripped,pressure tested head,a test will cost £25/£50,that's been cleaned properly should be worth £100 or so.

Post Sat Jun 01, 2013 3:09 pm

Thanks for the advice guys. I was thinking I'd probably do most of the work myself at some point, having taken apart a head before to replace a cam, re-seat the valves etc. I cant see any obvious cracking between the pots, but until i get it cleaned up, I cant be sure. I'll ask around and find out if anyone can clean it for me as a first step.

PS - no problem Byron - it was quite a laugh at the time!

Post Sat Jun 01, 2013 3:44 pm

Pressure test and keep it.
With the price of un-cracked dashboards fetching what they do currently, a good head
could well be worth a Kings ransom , in the not so distant future.
I have 4 of the buggers in a safety deposit box.

Post Sat Jun 01, 2013 6:22 pm

gooner1 wrote:Pressure test and keep it.
With the price of un-cracked dashboards fetching what they do currently, a good head
could well be worth a Kings ransom , in the not so distant future.
I have 4 of the buggers in a safety deposit box.

I have an uncracked dash,wanna do a swap?

Post Sat Jun 01, 2013 6:26 pm

daimlerman wrote:
gooner1 wrote:Pressure test and keep it.
With the price of un-cracked dashboards fetching what they do currently, a good head
could well be worth a Kings ransom , in the not so distant future.
I have 4 of the buggers in a safety deposit box.
I have an uncracked dash,wanna do a swap?

Ok, you install the dash in my car, and I'll put the head in you're
boot.