3mm head gasket or reduce 3mm packer??

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alanscottj
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Having a bit of mare trying to get the correct squish on my TS1. I have just fitted a 110 x 60 crank - measured port timings, they are spot on (190 exhaust 130 transfer) with a 3mm base packer. Up to now I am using a 2.5mm head gasket and only have a squish of 1mm. So, do I increase the head gasket to get a good squish or do I put a smaller packer on?

The head that i am using is a new MB CNC one.

Many thanks.

Scott
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drunkmunkey6969
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How do you plan on 'increasing' your head gasket?


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alanscottj
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drunkmunkey6969 wrote:How do you plan on 'increasing' your head gasket?

At the moment I am up to a 2.5mm head gasket so I am thinking to get a squish of 1.5 I need to use a 3mm head gasket. Chiggy at Lambretta Upgrades sells 3mm.

Or, do I put a 2.5mm base packer on? Which I already have in the shed.


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alanscottj
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Scratch that last message - I meant INCREASE the base packer NOT reduce it to 2.5 :roll:
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Norrie Bodge
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This may help ?

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drunkmunkey6969
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If you pop a .35mm gasket underneath your base packer everything should measure up ok.

I'm curious what type of ride you are trying to build.....race? What exhaust and carb will you be running?






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Norrie Bodge
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alanscottj wrote:Scratch that last message - I meant INCREASE the base packer NOT reduce it to 2.5 :roll:

2.5mm with a 1.2mm head gasket is whats on my S2 with a 60x110 crank & i love it ;-)

great ride... torquey azz
alanscottj
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drunkmunkey6969 wrote:If you pop a .35mm gasket underneath your base packer everything should measure up ok.

I'm curious what type of ride you are trying to build.....race? What exhaust and carb will you be running?






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Trying to build an engine for thrashing around the back lanes of North Wales. Carb is a TMX 35 and Franspeed Race.

After a bit of playing around last night I ended up using my old TS1 head and managed to get a squish of 1.2 using two gaskets - not ideal I know but it meant I could keep the base gasket as it was at 3mm keeping the port timings as they were.

I'm going to send my CNC head back to MB and have them machine it to suit a 60 stroke crank - it only costs ยฃ7 for labour so I might as well get it done, I can then get on with running in my new engine and swap the head the next time I need to do any work on the engine.

Managed to get her put back together today and boy does she shift! Been out and about today and the new crank has made a really noticeable difference, much smoother and goes off like a crosser! Once she's run in and the CNC head is back on I'll get her dyno'd and hopefully enjoy her for summer :D
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