AJP valve shims

[Jhonno]

Has anyone ever sourced them minus TVR tax? £5/6 a shim adds up quickly! I remember something about KTM or some sort of bike shims possibly being the same..

[Wolvesboy]

Will be interested in this as thinking of doing mine also (4.5). Sorry to jump in but perfect timing (excuse the pun).
Do you have the guidelines for required tolerances for both Inlet & Exhaust plus any information on the “paired” cylinders?
Thanks,

[Penelope Stopit]

What diameter are they?

[julian64]

would be great if they were made from tough material rather than simply case hardened

[Jhonno]

Penelope Stopit said:

What diameter are they?

8mm valve stems

[Penelope Stopit]

Sorry I can't help you, I recently visited many websites that supply shims but haven't seen the type you need

[TwinKam]

Wolvesboy said:

Will be interested in this as thinking of doing mine also (4.5). Sorry to jump in but perfect timing (excuse the pun).
Do you have the guidelines for required tolerances for both Inlet & Exhaust plus any information on the “paired” cylinders?
Thanks,

Exhaust 0.012"
Inlet 0.010"
It's overhead cam, so you measure the clearance on the back of the (fully exposed) cam lobe; there's no need to 'pair' cylinders as you would with eg a pushrod engine.

[TwinKam]

Penelope Stopit said:

What diameter are they?

They're 10mm OD, 8mm ID, vary in overall height from about 4.5mm to 5.5mm with a working thickness of 1.47mm to 3.47mm...

[Jhonno]

TwinKam said:

Exhaust 0.012"
Inlet 0.010"
It's overhead cam, so you measure the clearance on the back of the (fully exposed) cam lobe; there's no need to 'pair' cylinders as you would with eg a pushrod engine.

Manual says 0.008" (I) and 0.011" (E)?

[Jhonno]

TwinKam said:

Penelope Stopit said:

What diameter are they?

They're 10mm OD, 8mm ID, vary in overall height from about 4.5mm to 5.5mm with a working thickness of 1.47mm to 3.47mm...

Overall thickness - 2.54 to give shim thickness?

[TwinKam]

Jhonno said:

TwinKam said:

Exhaust 0.012"
Inlet 0.010"
It's overhead cam, so you measure the clearance on the back of the (fully exposed) cam lobe; there's no need to 'pair' cylinders as you would with eg a pushrod engine.

Manual says 0.008" (I) and 0.011" (E)?

They were revised to the larger settings, others will confirm, I'm sure.

[TwinKam]

Jhonno said:

TwinKam said:

Penelope Stopit said:

What diameter are they?

They're 10mm OD, 8mm ID, vary in overall height from about 4.5mm to 5.5mm with a working thickness of 1.47mm to 3.47mm...

Overall thickness - 2.54 to give shim thickness?

The 'shim thickness' part of the hat varies from approx 1.5mm to 3.5mm in about 40 steps IIRC, so the 2.54 you mention is within that range, yes. TVR Parts Ltd list them all but might not have them all, so you may end up 'adjusting' some.

[Jhonno]

TwinKam said:

Jhonno said:

TwinKam said:

Exhaust 0.012"
Inlet 0.010"
It's overhead cam, so you measure the clearance on the back of the (fully exposed) cam lobe; there's no need to 'pair' cylinders as you would with eg a pushrod engine.

Manual says 0.008" (I) and 0.011" (E)?

They were revised to the larger settings, others will confirm, I'm sure.

This is what I am wondering.. A few posts say stick with the build manual..

[Jhonno]

TwinKam said:

Jhonno said:

TwinKam said:

Penelope Stopit said:

What diameter are they?

They're 10mm OD, 8mm ID, vary in overall height from about 4.5mm to 5.5mm with a working thickness of 1.47mm to 3.47mm...

Overall thickness - 2.54 to give shim thickness?

The 'shim thickness' part of the hat varies from approx 1.5mm to 3.5mm in about 40 steps IIRC, so the 2.54 you mention is within that range, yes. TVR Parts Ltd list them all but might not have them all, so you may end up 'adjusting' some.

That's what I mean.. I think 2.54 is the internal depth for the valve to sit in, so the overall thickness - this gives the size of shim you have.

[Penelope Stopit]

Is there any chance that these are called lash caps rather than shims? I've found some lash caps at websites I've previously visited when looking for shims but the prices are high
Perhaps you have time to search for lash caps

[Penelope Stopit]

TwinKam said:

Penelope Stopit said:

What diameter are they?

They're 10mm OD, 8mm ID, vary in overall height from about 4.5mm to 5.5mm with a working thickness of 1.47mm to 3.47mm...

Ok, see above post

[TwinKam]

Penelope Stopit said:

Is there any chance that these are called lash caps rather than shims? I've found some lash caps at websites I've previously visited when looking for shims but the prices are high
Perhaps you have time to search for lash caps

'Lash' (amongst other things) is American for 'free-play' or 'clearance', so yes, I could imagine them being called that.

[TwinKam]

Jhonno said:

TwinKam said:

Jhonno said:

TwinKam said:

Exhaust 0.012"
Inlet 0.010"
It's overhead cam, so you measure the clearance on the back of the (fully exposed) cam lobe; there's no need to 'pair' cylinders as you would with eg a pushrod engine.

Manual says 0.008" (I) and 0.011" (E)?

They were revised to the larger settings, others will confirm, I'm sure.

This is what I am wondering.. A few posts say stick with the build manual..

They tend to close up in use anyway, but I saw a mention (and made a note of it in my big Cerb notebook) that they were revised, fairly early on ('97?).
Unfortunately I didn't note the source.

[TwinKam]

Jhonno said:

TwinKam said:

Jhonno said:

TwinKam said:

Penelope Stopit said:

What diameter are they?

They're 10mm OD, 8mm ID, vary in overall height from about 4.5mm to 5.5mm with a working thickness of 1.47mm to 3.47mm...

Overall thickness - 2.54 to give shim thickness?

The 'shim thickness' part of the hat varies from approx 1.5mm to 3.5mm in about 40 steps IIRC, so the 2.54 you mention is within that range, yes. TVR Parts Ltd list them all but might not have them all, so you may end up 'adjusting' some.

That's what I mean.. I think 2.54 is the internal depth for the valve to sit in, so the overall thickness - this gives the size of shim you have.

That is the least important of all the dimensions!... but, out of intetest, I've just measured a few from my collection and they are there or thereabouts, varying from 2.5 to 2.6mm

[Jhonno]

TwinKam said:

That is the least important of all the dimensions!... but, out of intetest, I've just measured a few from my collection and they are there or thereabouts, varying from 2.5 to 2.6mm

How so?! I have 16 shims I don't know the thickness of.. So I need to know what the depth of the pocket is, so I can work out the thickness of the shim!