Just thought I'd post this information on here as there are quite a few ST owners that would benefit from the above information.
There is pages of stuff on the STOC on this as whenever block mods are mentioned it only takes a little bit of fuel to start one massive fire so there are pages and pages of info.
Long and short of it is:
1) The Jamsport "Block Mod" (unofficially as they will never admit it but they have more or less been outed) is a shim that goes in between liners. Post from Don @ Kalmar Union:
I can offer this exact same procedure. You will need to book your car into an associate of mine who works in Coalville in Leicestershire. He is not VAT registered and you would need to pay by cheque or cash, otherwise you can pay me by credit card but I do have to charge VAT.
He has done many of these procedures already on these and similar Volvo engines over several years and they are all holding up well, he has also used the procedure to effect a repair on an already cracked block although it is unlikely that is a very long term fix for such damage.
As a preventive procedure it holds up well.
It simply involves fixing a slip(s) of metal into the area behind the weak liner/block, the cost is mostly in the labour of removing the head, the lesser cost is the gaskets and consumables required in re-assembly, the actual pieces of carefully formed metal used is pennies.
You are welcome to watch the entire procedure....but you might need to polish your tea making skills and provide a packet or two of jaffacakes as that is the preferred diet of the chap...and you need to be up for being ribbed unmercifully as he is inclined to take the pxxx even on first acquaintance, a very knowledgeable and capable fellow though.
Regards, Don.
It is exactly the modification offered by others.... you will be able to watch the whole proceedure, that is if you have the time and the price includes all new gaskets, seals, O rings etc.
Tim Williams is your man, he is in Coalville as I previously mentioned and the total cost is £615. He is not VAT registered and he has no credit card facility but he can frog march you to his nearest ATM and you can get cash to pay him. If that is a real ball ache then you can pay me by credit card but I have to charge VAT.
Regards, Don.
2) Pumabuild & Dreamscience are also offering the above block mod. Pumabuild also have released a lot of info on the ST blocks (pre and facelift) outlining their differences and development and research they've done. Like their facebook page to view all in detail and with pictures.
Post by Pumabuild:
Here is a bit of info about the I5 engine
Early engine blocks from an ST (pre face lift) Have different blocks to the face lift ST and RS.
Early blocks have a slot between the pistons ST engine (pre facelift)
Gap width 0.50mm
Depth 14.5mm
Later blocks also have a slot but it is not as deep.
Gap width 0.94mm
Depth 5mm
EARLY BLOCK
You can see the £20 note is deeper down the slit.
LATER BLOCK
You can see the £20 note is not as deep.
The slit is there to allow water to pass through in doing this the engine is kept at its desired temperature , if you give you car some stick the turbo builds up pressure and forces i...t to the engine.
This air becomes very hot as it is compressed by a big turbo. (Remember when you pumped up your bike tyre and the pump got hot?). This is what happens when you compress air.
The water in the engine has to take away this heat as fast as possible. In the little slit where the £20 note is the gap is very thin and the water has to pass through here to remove heat form the engine the problem here is when water gets hot and boils air bubbles form (look at the water in your kettle when it boils and you will see bubbles). When the water in this slit gets really hot bubbles form and this is bad as there is a heat build up and the water is no longer able to take the heat away from the engine and POP you are left with a great big dirty crack.
The RS engine has a lower compression ratio and this is why it does not crack. If you want to stop your block from cracking then simple fit lower comp pistons fitting shim blocks or deck plates is expensive and you have to remover the head. You would be far better off fitting lower comp pistons.
This I5 engine is also known as the narrow chassis engine as it had to fit between the chassis legs of the focus and Volvo cars. It was squashed together to allow this.
Just thought we would share this info with you alll
Alan Farmer
Pumabuild Ltd
Long and short of it is, block mod is a thin metal strip in between liner and block.
THE END!