E30/M20 head rebuild

Zach Hill · **Posted:** Mon Oct 22, 2012 3:42 pm

I've already spoken to a few people and gotten various opinions and have a game plan started already, but wanted to post and get any final input before I start ordering parts and tearing the car apart. Let me state that I'm a n00b when it comes to mechanical things, and I have never removed a head before.

Story: During my first session at VIR last week, the car lost power and began running rough. I brought it in and removed the valve cover only to find a broken rocker arm. It sheared in half and I found the broken piece, still intact. Considering it has 277K miles, has never been rebuilt, and that I will be tracking it for years to come, I figure now is the time to have the head serviced and all rockers replaced. The timing belt and water pump was replaced recently (thanks, Steven!), so I'm not planning on touching those. Anything else I should do?

For parts, I'm leaning toward these Ireland Engineering rocker arms which are cheaper and supposedly stronger than the OEM replacements. Their legality in SE30 is somewhat unclear, however there is an effort to have them explicitly legalized for 2013. In either case, if they're the same OEM spec, stronger, and cheaper, I'm going to get them and if people want to protest me, whatever. I'm planning on replacing all 12 rockers.
http://www.iemotorsport.com/bmw/E30-val ... armHD.html

And these ARP head studs:
http://www.iemotorsport.com/bmw/E30-eng ... dstud.html

Head gasket. I assume this should be replaced while I'm at it. Which one to get? PelicanParts has various brands at various prices. They sell "head gasket set" and "head gasket." Do I need the whole set?

Should I get a new cam shaft as well? Valve guides?

A couple SE30 guys recommended Cylinder Head Specialties in Wake Forest, and their business name seems to indicate they know how to do this job. I'll probably take the head there to do the rebuild. He quoted me roughly $275. Is that about right?
https://plus.google.com/112795008868896 ... l=us&hl=en

My plan is to remove the head myself, acquire the new rockers, and bring them all to the shop in Wake Forest and have them do a valve job and whatever else they need to. Are there specific things I should ask/tell them?

What about the bottom end? Previously the motor had great power on track compared to other E30s, and the car has been well cared for as far as I can tell, despite the high mileage. Should I bother spending more money to have anything done to it while I have the head off?

Feel free to share any experience or suggestions you think would help with this project. Thanks!

Steven Carter · **Posted:** Mon Oct 22, 2012 5:47 pm

That sounds like a good plan, one I still need to follow to get my Z back up and running. I would get the whole set. I don't recall what other gaskets I replaced other than the front engine gaskets, and IIRC those looked flimsy and probably need replacing whenever the front timing cover is removed. A few extra bucks now could save a lot of hassle later.

JamesMilko · **Posted:** Mon Oct 22, 2012 5:48 pm

How many valves is it? CHS charges a flat rate per valve. The Miata's 16 valve head was ~155 when I had it done a year or two ago. When you drop it off at CHS make sure you bring it with whatever gaskets/guides it needs, he doesn't stock the parts for them. Other than being out in the middle of nowhere I'd recommend him to work on whatever you need to have done. As far as the cams, as long as they look good there is no reason to replace them. They will likely have some wear marks on them but the general rule of thumb on metal-on-metal bits is if you can't feel it with your fingernail then it isn't an issue.

His main business is doing headwork for dealerships so they drop the head off with new wear bits.

Charlie Guthrie · **Joined:** Thu Aug 28, 2003 8:14 pm **Posts:** 832

My E30 track car had about 260K miles on it when the rod bearings failed. I replaced the rod bearings (with the engine in the car) because I was getting a little rattle. I should have gone ahead and replaced the main bearings at the same time. (I was just a little too cheap and not entirely sure that the mains could be replaced in the car). The following season I spun a main bearing and ruined an expensive crankshaft.

I know that the rod bearings can be replaced with the engine in the car and based on the engine on my engine stand I'm pretty sure that you could slip the replacement bearings in without much difficulty.

The only down side of replacing the main bearings with the engine in the car is that it is impossible to measure the crank journals, but you could use Plastigage to increase your comfort level. The Bently guide recommended assembling the crank bearings one-at-the-time with the engine on the stand so that you could freely spin the crank after each bearing is installed; that way ensuring that there was no interference. Naturally that isn't possible with the engine in the car.

As an aside, I witnessed someone replacing a broken lifter in the pits at CMP at an HPDE, but he really seemed to have done it before.
Charlie G

Jason Tower · **Joined:** Wed Jun 11, 2008 3:31 pm **Posts:** 1173

use goetze head gasket, the rest of the gaskets can be victor rainz. i didn't use arp studs on my motor, nor do i hear of many se30 racers using them either. with an iron block stock bolts are probably fine. if the cam has no visible wear and you can't feel anything unusual it's probably ok, but you could have it degreed while it's out. i understand replacement camshafts are expensive. inspect the bores while the head is off, if it was strong before the rocker broke and didn't use too much oil the odds are you won't find anything. bottom end is pretty much separate from top end as far as labor and access goes, usually the only thing i hear about is rod bearings but even that is fairly rare. knowing your hot oil pressure is at least a rough indicator of how "loose" the bottom end is. if you do pull the pan you might as well install a baffle and/or crank scraper for better oil control, especially now that stickier tires will be used in 2013. george at chs did my m20 head (along with all of our honda motors) and can be trusted to do good work at a reasonable price.

Charlie Guthrie · **Joined:** Thu Aug 28, 2003 8:14 pm **Posts:** 832

Jason Tower wrote:

Quote:

you might as well install a baffle and/or crank scraper for better oil control

Hey Jason do you have any good leads on plans/instructions for a baffle or crank scraper? Since I have the engine on the stand now would be a good time to take care of that myself.
Charlie G

Jason Tower · **Joined:** Wed Jun 11, 2008 3:31 pm **Posts:** 1173

i don't be the spece30.com forum would be a good place to start

TomFreeman · **Posted:** Mon Oct 22, 2012 10:08 pm

Charlie Guthrie wrote:

Jason Tower wrote:

Quote:

you might as well install a baffle and/or crank scraper for better oil control

Hey Jason do you have any good leads on plans/instructions for a baffle or crank scraper? Since I have the engine on the stand now would be a good time to take care of that myself.
Charlie G

The easy answer is the PooreSports baffled oil pan. It's a modified stock pan with a deeper sump and a very interesting baffle system. I have one to go into my car this winter. It's well respected in the SpecE30 world and used with and without crank scrapers successfully.

Jason Tower · **Joined:** Wed Jun 11, 2008 3:31 pm **Posts:** 1173

sort of ironic considering zach and i were talking to paul poore at vir shortly after this all happened

TomFreeman · **Posted:** Tue Oct 23, 2012 10:18 am

Jason Tower wrote:

sort of ironic considering zach and i were talking to paul poore at vir shortly after this all happened

Paul is a good guy...which reminds me, I owe him a stock oilpan

If you're spending money on his oilpan, I believe he now has a skid plate designed to give some extra protection to that pan.

Zach - I haven't seen it explicitly mentioned, but with an M20 with that many miles on it, I'd think you would want new valve springs as well. Yours have to be pretty tired.

Zach Hill · **Posted:** Tue Oct 23, 2012 11:44 am

A big thanks to each and every one of you who replied. This is all great info and helps a lot!

Here's my "definite buy" list now:

IE rockers

Victor Reinz head bolts

Maybe buy list:

Once the head is off, I will inspect the cam shaft and go from there. Is there a way to determine if I need new rod and/or main bearings? How difficult are these to replace with the head removed?

On the oil baffle/crank scraper. Is this easier to install with the head off? I thought the pan is on the bottom, so seems unrelated, but I don't know what I'm talking about. Is this a necessity or highly recommended for a 100% track car? I presume it prevents oil starvation in high-G cornering. My car hasn't burned any oil since I bought it, and it has done 6 track weekends, although only on StarSpecs. From a quick search it sounds like the PooreSports pan is $550. The cost of this rebuild is escalating quickly... :cry:

Thanks again, everyone. These forums are invaluable!

BretLuter · **Posted:** Tue Oct 23, 2012 12:07 pm

Sounds like you need to decide whether or not to tear into the bottom end, but like Jason said, if it was OK before, it's probably still OK. And as you've found, the costs add up very quickly when you start adding things to your list.

I don't know anything about the Paul Poore baffle/pan, but I know several SpecE30 guys who have successfully used these: http://www.crank-scrapers.com/bmw_m20.html (AND they're alot cheaper than a baffled pan).

You might want to go ahead and buy the whole head gasket "set" because you'll also need the valve stem seals for CHS to rebuild the head, and there are some other gaskets you'll probably want to replace such as intake and exhaust manifold gaskets, valve cover gasket, etc and those are typically included in the set (the exhaust manifold "heatshield" gasket is sometimes not included- but check the set description and it should say).

You probably want to buy 12 new copper-plated nuts for the exhaust manifold, and maybe some new exhaust studs, as they often back out when you try to take the nuts off. There are also 6 larger copper plated nuts on the exhaust manifold downtubes that you might want to buy new. Timing belt + tensioner, as well as water pump should be on your list.

As Charlie mentioned above, it is possible to replace the rod bearings with the engine in the car, but to do rod + main bearings, it's probably 100000% easier to pull the engine.

Steven Carter · **Posted:** Tue Oct 23, 2012 1:39 pm

I think if you can maintain good oiling in the bottom end of the car, pre-emptive bearing replacement may not be necessary. At least, not yet. SpecE30.com is a wellspring of good info, both cautionary and otherwise (Ranger's adventures in oiling system improvement immediately come to mind). Seems most do fine with a crankscraper and good working oil pumps, but if you have money to blow the pan is good too.

Maybe call PelicanParts and ask specifically what is in their gasket set, then corroborate with CHS to see what else you need to fill in the gaps?

TomFreeman · **Posted:** Tue Oct 23, 2012 2:58 pm

BretLuter wrote:

Sounds like you need to decide whether or not to tear into the bottom end, but like Jason said, if it was OK before, it's probably still OK. And as you've found, the costs add up very quickly when you start adding things to your list.

I don't know anything about the Paul Poore baffle/pan, but I know several SpecE30 guys who have successfully used these: http://www.crank-scrapers.com/bmw_m20.html (AND they're alot cheaper than a baffled pan).

You might want to go ahead and buy the whole head gasket "set" because you'll also need the valve stem seals for CHS to rebuild the head, and there are some other gaskets you'll probably want to replace such as intake and exhaust manifold gaskets, valve cover gasket, etc and those are typically included in the set (the exhaust manifold "heatshield" gasket is sometimes not included- but check the set description and it should say).

You probably want to buy 12 new copper-plated nuts for the exhaust manifold, and maybe some new exhaust studs, as they often back out when you try to take the nuts off. There are also 6 larger copper plated nuts on the exhaust manifold downtubes that you might want to buy new. Timing belt + tensioner, as well as water pump should be on your list.

As Charlie mentioned above, it is possible to replace the rod bearings with the engine in the car, but to do rod + main bearings, it's probably 100000% easier to pull the engine.

The reason I suggested the better pan first is the ease of install. From what I've read, none of the crank scrapers are a "bolt on and go" affair. There is some level of trimming and tweaking to get them to fit perfectly. Since I haven't done it myself, I cannot speak authoritatively, however. The pan, while $, is a straight bolt on affair...granted you have to drop the front subframe a bit to install. You'd have to do that on the crank scraper anyway.

For a car that has spec e30 aspirations, you want to do something for oil control. There have been enough oil starvation failures on M20s over the years. It's a well known, accurately diagnosed issue.

I also like the pan because it adds to your oil capacity. I believe it's about 7qts with the PooreSports pan, and more oil capacity is almost always a good thing.

Zach Hill · **Posted:** Tue Oct 23, 2012 3:07 pm

TomFreeman wrote:

The pan, while $, is a straight bolt on affair...granted you have to drop the front subframe a bit to install. You'd have to do that on the crank scraper anyway.

Oil pan replacement would be separate from head work, right? Drop subframe, drain oil, unbolt pan, install new pan, bolt back up, reinstall subframe, add oil, profit?

What I'm getting at is it sounds like I could do the pan upgrade next year separate from the head rebuild, before racing with sticky tires.

Thanks!

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