Opinions on uprated head gasket for Evo 5 LET?

[Rob77]

I have a Nova C20LET on Evo 5 chips, which has needs a new head gasket, as the standard one has failed.
I just want some opinons on whether I should stick with a standard gasket, or use an uprated one...
Engine internals are standard bar rod bolts...
Will be upgrading turbo soon though...
Also, what will need skimming (head / block) when the new gasket is fitted? I gather it depends on the type of gasket fitted...
Thanks a lot.
Rob.

[Stuart]

you want the least skim possible to keep the CR right (low)... if you get a cometic style gasket then you will need to make sure that the block and the head are perfectly flat.

[Rob77]

So if I use a normal gasket, I wont need to skim either?

[Rob77]

Or just the head?

[Stuart]

tbh id always make sure that the block and head were flat even when using a std gasket as its best to ensure the longevity of the build.

[Philsutton]

im using a z20let steel one an its been fine so far

[Rob77]

Right, so how do I check the block is flat? Do I have to strip it an take it to an engineering place?

Anybody know of anywhere round Nottingham I can get the head skimmed for a reasonable cost?

Phil, did you have the block / head skimmed when you put your Z20LET gasket on? Also, did you remove the rivets off the gasket?

[Rob77]

Just been looking at gaskets on ebay and found the normal standard ones, ie:

http://cgi.ebay.co.uk/VAUXHALL-2-0L-HEAD-GASKET-NON-ECOTEC-VBS-720_W0QQitemZ200105961378QQihZ010QQcategoryZ10404Q QrdZ1QQcmdZViewItem

But the company who sells the above also has this:

http://cgi.ebay.co.uk/VAUXHALL-2-0L-UP-RATED-RED-TOP-HEAD-GASKET_W0QQitemZ200106287224QQihZ010QQcategoryZ104 04QQrdZ1QQcmdZViewItem

Is this a Z20LET jobbie?

Also had a look on Regals website at their "uprated" or Z20LET gaskets for sale (seen here: http://www.regal-shop.co.uk/acatalog/Calibra_Tuning_Service_Items.html) and had a quick chat with a guy there who said if I had a head and block skim I will need 2 gaskets, if I skim head I should use 1 gasket.

Just need to decide whether to use a standard gasket or a Z20LET (Regal) jobbie...

Opinions?

[Dan 130]

you could just use a precision straight edge and some feeler gauges to check it your self

[Rob77]

you could just use a precision straight edge and some feeler gauges to check it your self

Thats a pretty good idea!

Found these, who are apparantly pretty damn good:

http://www.johnarnoldengineering.co.uk/

They said to only skim the head.

?25 aint too shabby either! Just need to take cams off, can leave valves in!

Easy peasy!

[redrocket]

IME ive never had to get the block skimmed when using cometic/z20let head gaskets just clean up skim on cyl head

[Stuart]

I guess it depends on the faith you have in the block.

Lots of people who have fitted MLS gaskets have had issues where their block wasnt flat and it leaked...

meh try just the head you might be lucky.

[CP]

Generally speaking the blocks in cars are normally ok cos they are made from steel which doesn't warp easily or get damaged during the clean up process. The heads are made of soft aluminium alloy and are very susceptible to warping and clean up damage. They are usually warped by incorrect loosening procedures. As a general rule of thumb it is a good idea to skim them as a routine which providing they aren't warped seriously will remove only a few thou off and have a negligible effect on CR. After this has been done the surface is flat and has machining marks which are ideal to help clamp the gasket down properly especially around the shoulders of the cylinders where gasket damage usually starts.

[Rob77]

Thanks for all the replies guys.

Will just be skimming the head and fitting a Z20LET metal jobbie.

Rob.