TOPIC:

turbodarnell wrote:

i plan to run 12 psi or so normally with the occasional 20 psi run with some higher octane fuel. ill probably eventually get an f40 turbo as well if the f25 back pressure gets too high.
 

Pretty sure with those boost levels you should look at getting a lock up clutch.

i certainly will! anyone got a karate glide? 

if i double up on base gaskets that should get me down to the low 8's like im after? do you recommend an mls head gasket or cometic copper? thanks 

turbodarnell wrote:

i certainly will! anyone got a karate glide? 
 

Karata and Denco Glides are pretty rare but they do come up on Ebay occasionally.

MRE and MTC are more common, just search drag bike lockup clutch because they are listed often on there.

turbodarnell wrote:

if i double up on base gaskets that should get me down to the low 8's like im after? do you recommend an mls head gasket or cometic copper? thanks 

If you haven't had the block piano wired  then MLS head gaskets are the way most are going on their turbo builds including myself .
They can handle the extra pressure without needing the liner tops wiring so less hassle not having to get the grooves machined every time you change a block or liner.
For the lockup clutch, get yourself a basic single stage one from MRE if it's just for the street.
If you think you may do a bit of proper sprinting then get a 2 stage which is basically the same as single stage except the posts are machined so you can use shims on the clutch springs to fine tune the static pressure for better launches.
As for the base gaskets, doubling up isn't very accurate and you will be better off using a aluminium spacer of the required thickness with no base gasket and seal it with Loctite 30/20..

MTC sell Z1 aluminum base gaskets up to .060" thick depending on the liner diameter.

i would have to use a gasket on the top portion of the aluminum spacer correct? that .02 gasket thickness makes a difference according to my compression calculator

You could use a gasket under or over the spacer, non at all or stacked spacers depending on the spacer thickness you have and the spacing required.
The 0.02" ( 0.5mm ) thickness of the stock base gasket equates to approx 2cc .

thank you so much you are a wealth of knowledge are the pistons typically 0 deck on a stock untouched motor or are they down in the barrel. thanks!!!

I've never had a stock motor with zero deck height.
A motor i'm building now that already has the block decked an unknown amount to level in the new liner tops is still 0.35mm below the surface.

ah that is very significant. it appears i will have to pre assemble the engine and check deck height then order the corresponding spacer needed. thank you!

zed1015 wrote:

I've never had a stock motor with zero deck height.
A motor i'm building now that already has the block decked an unknown amount to level in the new liner tops is still 0.35mm below the surface.

Rob just a question, do you know how much you could deck a stock A2 block before you compromised the strength of the retaining/sealing lip on the liner ?? (just spit balling at this stage)