Cylinder head refurb and improvements.

[scoobyh123]

That was pretty much what i meant to be honest, just couldn't find the right worms at the time!

Deburring and polishing (even slightly rough polishing) the inlet tracts would definitely pay dividends - more than that could as you say be detrimental to low end torque. Cleaning up the throttle body and main plenum would help too, especially if you could get a bit more volume in the plenum. I can't remember if the inlet tracts can be split from the plenum on the T but if so, matching the joins would obviously help too.

Either way, getting everything as "right" as it can be will help the power, smoothness and response and almost certainly the economy too.

Looking forward to the road test report on this one!

[traineefarmer]

The inlet tracts don't detach from the plenum, but split half way to allow removal of the injectors. I'll be doing some cleaning and matching there too.

Looking forward to the road test report on this one!

I'll have to take you for a spin. I seem to remember you mentioning a nice straight fenland "test track" near yours.

[scoobyh123]

Sounds like a plan! The test track was much more convenient before i moved here but sure we can sort something out.

[traineefarmer]

I removed the head today and I breathed a sigh of relief when I saw the piston tops and bores. There is far less wear than I was expecting to find on a 120k Longbridge built engine. Some honing marks are still visible and no vertical scoring. All good.

The turbo was looking in far worse health.

God knows what could have caused that sort of damage to the compressor wheel.

Here is the root of all my power loss problems. Completely buggered exhaust valves.


And here is some mystery damage on the head surface.

I don't know how this could have occurred. I certainly didn't do it removing the head and I can't see any evidence that the engine has ever been apart before. Could this have happened in the factory?

Not much to do now before I'm ready to reassemble. Most of the components like manifolds have been port matched and swapped onto the new head and a few more minutes with a variety of power tools will have the top of the block and pistons clean.

Also, I've made some nice new steel dowels.

[scoobyh123]

More good work Tom - i expect some twigs or similar got past the air filter at some point and damage the compressor wheel - either way it's not good for balance and power from the turbo!

[traineefarmer]

More good work Tom - i expect some twigs or similar got past the air filter at some point and damage the compressor wheel - either way it's not good for balance and power from the turbo!

I see where you're coming from, but that would indicate that it had been run for a period with no filter and there's no other internal damage to show for this. I wondered if some pillock had stuck a screwdriver (or finger!) in there to check if the turbo was spinning.

[scoobyh123]

That was in fact what i was thinking, it had been run for a while without an air filter - perhaps the turbo wheel chewed the foreign bodies to pulp before any further damage could occur?

The alternatives of a screwdriver or finger crossed my mind as well but discounted it as i really didn't think anyone coulc be that daft. Then again........

[traineefarmer]

Got it all back together and running today. It now runs and goes and a T series should.

A lovely nearly silent idle land an immense linear shove in the back when you get your foot down. It's going to need a few miles to bed everything in but improvement in drivability is fantastic.

[scoobyh123]

Excellent Tom! Goes without saying to keep an eye on the coolant level for a while just in case of any hidden air locks but i'm sure it will be fine.
Nice to hear it now goes like it was meant to!

[traineefarmer]

Don't worry, that will be a daily check for a few weeks as will general leak and looseness checks. There's definitely a lock somewhere as about a litre less coolant went back in compared to what came out!

[scoobyh123]

Try running round for a while with the heater on its hottest setting - i've found the heater is prone to air locks when the system is drained.
Might pay to keep a pair of clean shoes ready in the boot for those "farm fresh" after work times though!

[Slamm]

Got it all back together and running today. It now runs and goes and a T series should.

A lovely nearly silent idle land an immense linear shove in the back when you get your foot down. It's going to need a few miles to bed everything in but improvement in drivability is fantastic.

Great news Tom, I noticed a big improvement when I did mine, no where near as much work as you've done but still a lot quicker. Trouble is now I like to hang on to second and third gears more and feel that torque steer.

Shaun

[traineefarmer]

YES! It wasn't noticable when the engine was poorly, but when I first booted it in second, I thought I'd blown a tyre! I'm getting used to holding the steering a bit tighter now...