Valve Guides

[dusty]

I have these valve guides for the Twincam but they came from an unknown source, can anyone confirm if they look like the correct "bronze" guides for unleaded use?

See attached picture

Cheers
Jon

[rgh0]

They look like Bronze guides I have seen but no guarrantees if from an unknown source.

I dont believe unlead has anything to do with guides. The newer bronze guides have better wear characteristics than the original cast iron guides but unleaded versus leaded has no impact on guide wear.

cheers
Rohan

[bill308]

I agree with Rohan but let me add, the bronze guides are a much better conductor of heat from the valve stem, helping keep the valves a little cooler.

The issue with unleaded fuel is the valve seats. They should be hardened to protect them from recession.

Bill

[elangtv2000]

These do look correct; I have just completed an engine rebuild and replacement of guides and seats, and have recently sold an excess set of guides. Measurements will confirm.
Cheers,
Greg

[Foxie]

Hi Jon,

Who is going to replace your valve guides ? Are the seats being replaced as well ?

Lotus heads use alloy steel seats and valves, unleaded is not normally a problem, as it would be with cast iron heads and directly machined valve seats.

I would recommend using a Lotus specialist such as QED for this work.

Sean Murray

[dusty]

Hi Jon,

Who is going to replace your valve guides ? Are the seats being replaced as well ?

Lotus heads use alloy steel seats and valves, unleaded is not normally a problem, as it would be with cast iron heads and directly machined valve seats.

I would recommend using a Lotus specialist such as QED for this work.

Sean Murray

Sean,

I don't know yet, I had thought about doing it myself (guides and seats)!

Unfortunately QED don't do this work anymore they are now purely a parts supplier.

Do you know of any other specialists?

Regards
Jon

[Foxie]

Jon,

I'm surprised to hear QED are no longer doing this, the did an excellent (if slightly expensive) job on my Twincam head, replaced all valve seats, guides, cam follower sleeves, porting, machining deeper spring wells for high lift valves etc.

Burton's specialise in Ford/TCs components, I don't know if they do machine work, but it's worth a call.

Try Hi Precision in Tullow-: 059 915 1444

or Howard Engineering in Glasnevin 01 8827555

Both do excellent hi tech machine work, and very reasonable rates.

Howard Engineering had to be prodded a bit to get my crankshaft done in time !

Sean

[tdafforn]

Burton do do work on engines (although my guess is that they farm it out).
Otherwise there is Wilcox.
http://www.wilcoxengines.demon.co.uk/xflow.htm
Tim