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Cylinder head project now underway

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Brosky

Brosky

Great Pumpkin
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I received my cylinder head yesterday as it literally bounced it's way into my life, thanks to the UPS driver actually "dropping it off" at the rear door. My wife heard the bang and went out to see what had happened. Fortunately, he dropped it on the valve spring side and I don't think anything was damaged.

I'm not about to take any chances, so I delivered it to a good local machine shop, (Motor Tech in New Bedford, MA) who does heads for Triumphs regularly, to be checked and tested.

I measured the head thickness in several spots and came up with 3.540",which is thicker than it was advertised on eBay. I asked Bob at Motor Tech to check for any cracks first, measure the thickness and then the check the deck surface before I decide what I want to do.

I'm thinking about Richard Good's chart and I'd like to stay at about 8.0-8.5 to 1 compression. That will give it a bit more zip, but no major dieseling or pinging issues.
https://www.goodparts.com/tech_docs/TR6_Compression_Ratio.html

I asked Bob to quote the following:

Take another .050" off of the deck if it can stay at 8.0 - 8.5 to 1 compression
New valve guides & seals
New hardened seats and grind valves accordingly
New freeze plugs
Shim and set spring height and replace weak springs and retainers.
CC combustion chambers and remove any sharp edges

Anyone have any other thoughts about machine work, while it's there?

This is what I'm starting with, so it doesn't look too bad so far.

head 001 (Custom).jpg


head 008 (Custom).jpg


head 009 (Custom).jpg


head 010 (Custom).jpg
 
Now Paul, you know you have to bump it to 9.5:1 and put in a GP2 cam! Stop kidding yourself. It doesn't cost any more to go first class......

Heck, everything else is already done. Why bump it up to a 1970 level. Go for it..
 
Oh man, I'm sorry. My wife said that Bill is not allowed to reply any more and Tom is getting awful close to the "no reply" list.

Dale's too preoccupied with his front end, so he's not a worry at this time. But Shawn may be thinking and lurking out there.
 
Paul- The head thickness has a little to do with the compression. You need to know exactly where it came from and the volume of the valve area and your cylinder volume to know what the compression is or will be. Is say to really enjoy your trip carbs go at least 9 to 1 and if your still running the stock cam,Oh dear!
If thinking all the things mentioned and cam bearings roller 1.55 rockers...
I love to spend your money!
 
Best not count me out yet, Paul!

Wendy will be in Maryland next week and she has
yer address.

It's only a matter of time before I get the suspension
and steering sorted out. I'm guessing the next major
Crypt Car break down will involve the engine blowing up.

DPO Pedro most likely used K-mart epoxy to fix the cracked
head before he sold the car to Wendy.

So Wendy might be looking for a decent TR6 head!

regards and WOW! Any hand-me-downs you care to ........

d /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
I just bought another GT6 block, crank and rods. That head would be a nice addition to the package, Paul! I'm going for 11:1 or better, though. Just to add a little zip to the street ride. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Jeff
 
I was going by the Richard Good chart as a guideline. Tom was going to measure his for me as well. I would have thought that there was some standardization on these, but I do see your point as there were differences between the early and later heads and piston dome height/size, etc.

I've got my eye on a nice little 73K mile engine that may find a home by winter. I only have 53K original on mine, but if the new head creates any problems, well then....

I'm sure that you're way ahead of me by now.

Little by little.....

Dale, I know that you're there plotting as well.
 
Paul, I have not been out to the shop for a couple days and do not know if mine has been done yet. I will measure mine for you but, they are not all the same. Best to cc yours and go by that. Ted at TSI told me to only use a chart for an idea of where the ratio may be but that is no guarantee.
 
I had planned to have it CC anyhow. Thanks for the advice.

Good luck on yours and keep those pictures of the paint and engine coming.
 
valve springs from British Frame and engine.

If you're thinking of bumping lift by either rockers or cam, might consider light retainers. But I hear the aluminum ones are problematic, short lifespan.

what seals is he putting on, umbrella or spring sleeve?

Minor clean up on the manifold holes matching a gasket to flange opening.

Cc the chambers and equalize them.

When they do the valves how many angles are they going for, slight backcutting has gotten good reports.
 
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