|
700/900 Series General Forum for the Volvo 740, 760, 780, 940, 960 & S/V90 cars |
Information |
|
Cometic MLS head gasketsViews : 855 Replies : 13Users Viewing This Thread : |
|
Thread Tools | Display Modes |
Oct 19th, 2019, 14:07 | #1 |
Member
Last Online: Today 08:01
Join Date: Jul 2013
Location: Leics
|
Cometic MLS head gaskets
Hi everyone
I'm interested in hearing the experiences of any members who have used said gaskets. In particular, if anyone with a B200 has used them. Reason being that I want one for my B200, however the ones I have seen have a 92mm diameter hole, whereas the combustion chamber is 94mm & the cylinder 90mm (measurements rounded to nearest mm). This means a 1mm portion of the gasket will be in the combustion chamber. Has this made a difference to anyone using them? Think the volvo gaskets are 94 or 95mm. Wondering if it's worth the faff of getting a 94mm diameter one made. Tim |
The Following 2 Users Say Thank You to 230ina245 For This Useful Post: |
Oct 19th, 2019, 19:29 | #2 |
Premier Member
Last Online: Apr 15th, 2024 09:22
Join Date: May 2012
Location: Lakenheath
|
Why do you want or think you need an MLS gasket? Red-blocks don't normally need black magic like that, especially on the B200.
__________________
Cheers Dave Next Door to Top-Gun with a Honda CR-V & S Type Jag Volvo gone but not forgotten........ |
The Following User Says Thank You to Laird Scooby For This Useful Post: |
Oct 20th, 2019, 12:15 | #3 |
Premier Member
Last Online: Oct 26th, 2023 20:42
Join Date: Jun 2010
Location: Thurrock
|
You could try for example http://www.ferriday.co.uk/mls-head-gaskets/ to have the Cometic gasket modified.
I just found them by an internet search. That's all I can say. |
Oct 21st, 2019, 14:18 | #4 |
Member
Last Online: Today 08:01
Join Date: Jul 2013
Location: Leics
|
Hi Dave
Going for a cylinder head with tight squish. The cometic gaskets are produced with a range of known compressed thicknesses thus allowing for an accurate squish calculation to be made. Er, also what do you mean when you say "especially on the B200". Stephen - thanks for the link - useful to know. As I haven't ordered a gasket yet I should be able to get the right size from Cometic - once I've worked out what the right size is! I've read somewhere that they make them to order. The size I'm thinking of has already been made (& on their database) but not in the thickness I need. Tim |
The Following 2 Users Say Thank You to 230ina245 For This Useful Post: |
Oct 21st, 2019, 14:48 | #5 | |
Premier Member
Last Online: Apr 15th, 2024 09:22
Join Date: May 2012
Location: Lakenheath
|
Quote:
What is your thinking about a tight squish? Are you trying to get it to run leaner or something along those lines?
__________________
Cheers Dave Next Door to Top-Gun with a Honda CR-V & S Type Jag Volvo gone but not forgotten........ |
|
The Following User Says Thank You to Laird Scooby For This Useful Post: |
Oct 21st, 2019, 16:25 | #6 |
Member
Last Online: Today 08:01
Join Date: Jul 2013
Location: Leics
|
Ahh - I see what you mean.
Unfortunately I am going in the opposite direction of running lean - higher boost & higher compression. Should raise its stress levels a bit! Lean running is definately not on the cards. I have found that the normal head gasket gives up sooner or later at about 25 psi. I decided to start from scratch & try to build an engine combo to take this in it's stride. Tim |
The Following 2 Users Say Thank You to 230ina245 For This Useful Post: |
Oct 21st, 2019, 17:56 | #7 | |
Premier Member
Last Online: Apr 15th, 2024 09:22
Join Date: May 2012
Location: Lakenheath
|
Quote:
Just out of interest, are you converting it to LPG at the same time? Although pretty new on the market, Liquid Phase LPG injection kits are available here now abd that would give you a couple of advantages - first, charge-cooling and second, would help cool the pistons and head, allowing you to run higher boost plus the LPG is about 105 octane so is less likely to cause detonation too.
__________________
Cheers Dave Next Door to Top-Gun with a Honda CR-V & S Type Jag Volvo gone but not forgotten........ |
|
The Following User Says Thank You to Laird Scooby For This Useful Post: |
Oct 25th, 2019, 18:51 | #8 |
Member
Last Online: Today 08:01
Join Date: Jul 2013
Location: Leics
|
Yes - I was going to do the "group A" hole mods to the head. I'd heard about the poor cooling - on the 240 the heater takes coolant from the back of the head and it returns to the pump. When the heater is switched off no coolant flows.
I was thinking of rigging up a diverter valve which would allow coolant to the heater & switching the heater off would divert coolant back to the pump. I've even seen the heater outlet on the head used to take coolant forwards to a fitting fixed in the thermostat housing. I had not considered using LPG - had a bit of a look to see if it could be used in a similar way to NOS or water/meth injection but it seems to only be used instead of petrol altogether. I am too far down the route I am taking to make such a drastic change. Still looking into possiblities though as I have been planning on using water/methanol injection as part of the setup. Tim |
The Following User Says Thank You to 230ina245 For This Useful Post: |
Oct 25th, 2019, 19:13 | #9 |
VOC Member
Last Online: Apr 12th, 2024 16:38
Join Date: Jun 2009
Location: Swineshead/Salford
|
no
If you want a high power motor a b230fk is a much much better starting point.
The bore allows bigger valves and flows better. You'll be spending money on a lesser end product. You'll have to skim the head and deck the block to run a cometic gasket anyway. It's all been done before and nobody uses a b200 block.
__________________
new engine! new car! |
The Following User Says Thank You to barkster1971 For This Useful Post: |
Oct 25th, 2019, 22:54 | #10 |
Trader Volvo in my veins
Last Online: Today 21:53
Join Date: Dec 2004
Location: Anglesey
|
The Cometic gaskets can be tricky to get a good seal on. You MUST have both the head AND the block surfaced perfectly flat to get a lasting seal.
Below 500BHP I would not even consider one and there are lots of engines out there in the 6-700 region still using a standard gasket. With the B200 I would be more tempted to machine the raised crown of the pistons and just throw more boost at it, maybe go long stoke |
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
Thread Tools | |
Display Modes | |
|
|