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MGB-GT I have to replace the head on my '71 BGT

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Be sure and do a compression check before pulling head to use in diagnosing your engine.
I just did a valve job on my '64 B. The machine shop made it like new. What is now occuring, which I understand is common, is increased 'blow by' past the pistons. Since I have a downpipe on the side of the engine, I experienced some oil dripping/spraying onto the exhaust header at highway speeds (very annoying burned oil smell)
For the time being, I added a length of vinyl tubing to the downpipe, extending it to the area below the header pipe. Next? either new rings, maybe a pcv valve?
 
Hi Lou, Thanks for the info! I did do a compression test. The results are further back in this thread. I suspect I may have the same problem but I also have a PCV which would pull the vapors and reburn them through the carbs.

Eric, I checked and have an 18GK-WE-H block. My head has plugged airline ports. I don't know if the block is original but, according to the MOSS catalog, it's correct for the car. If I pull the head, can I tell what type of pistons I have from looking at the crowns?

Adam
 
Forgot an another huge important point:

Do not put a 73-74 head on earlier engines because you will have to have your engine block machined. These heads are know as the MGB big valve head (1.625 intakes) and WILL hit the block deck.

It is described in the article mentioned in my last message. /ubbthreads/images/graemlins/nopity.gif
 
Eric, that article is insane! The guy knows so much! I used to work in VW machine shop and I recognize many of the concepts and procedures he describes. Man it's been a long time....

Based on his assessment (just as you described as well), I can't use the '77 motor so on to coming up with the next plan.

Will your head work properly on my 18GK (assuming no smog needed)?

Thanks again! Adam
 
Assuming you will do a full rebuilt before. Which includes crack testing (better be save than sorry).

You must be able to locate a head in california from your local British parts store..

You may want tor read also Peter Burgess book on How to power tune an MGB.
 
The conclusion(I hope!) of the cracked head saga. Yea!

First I tried an eBay head. The local shop magnafluxed it and (of course) it was cracked inside. The seller refunded my money except shipping. (Cost of lesson learned.)

I then bought a complete new aluminum head from Northwest Imports. The ports looked good and I didn't have the time, patience or tooling to learn how how to port it. The water passages, eapecially around the heater valve were full of flash so I cleaned them up with a Dremel tool.

The head nuts were beat up and mismatched but the cylinders looked great (pistons marked .030 over)so I just bought nuts, new head and exhaust studs, exhaust nuts, hoses and misc.

After much scrubbing and painting in the engine box, I reassembled everything, adjusted the lash and fired it up. That was early September. It ran fine so I drove it for 90 or 100 miles in several shorter trips.

After that, I stripped everything down, retorqued the head (which hadn't moved) and the exhaust nuts (which had). I set up the carbs, following the Chilton guide and instructions with the carb tune kit from Moss.

It runs like someone kicked it!

I took it last week to our local MGB mechanic (Darrin's in Chatsworth, CA) and he put my Mike Goodman built OD trans in for me. That makes the car cruise so much better and clears space off my garage floor!

Now I think I need the radiator rodded out since it STILL runs hot in stop-and-go traffic. I'll get it checked out soon.

Thanks to everyone for your ideas and support when I first got into this!

Adam
 
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