4 cylinder bore & stroke combinations + max bore & stroke list

Unless there is a piston / bore problem or any other major problem with the bottom i would keep bore and stroke as std.and turn attention on other performance tweaks that can be done

Is not because a 100 mm crank and large bore 84,5mm piston can be fitted thats it is also a good idea... as you want a reliable engine, there are a few things that need respected

Bore diameter, stay on the safe side 83,5 mm or 84mm which leave only 4 mm between bores

As its a 220 mm bloc with 144 mm long conrods... 144/ 92,8 = 1,55 rod / stroke ratio, its already close to 1,52 which is regarded as a minimum … with a diesel crank this becomes 144/ 95,5 = 1,50...its prety much stretching the edge...and a longer rod/ taller bloc would be advisable

 

yep a bit low on p2 (oil (to seal)in cyclinder/comp test) suggesting cylinder rather than valve let by so bore may need attention.
Thanks for the response, so not really worth cc increase if having to do bore work then.

to overcome low comp:
best practice to replace pistons (as a set) ?
ovesize rings is not recommended ?

 

Good bores, pistons, sealing is key to any good engine. See what size and price oversized pistons (set) are available. Machine shop
will charge more for more material removal. Rebores aren't cheap.
High performance engines use thin rings and short pistons typically, so look at all the dimensions before deciding.
Your machine shop may (will..) want to supply the pistons when they rebore your block. Make sure they supply what you want.
Lastly, the last rebore I had done I made an assumption the shop would remove the oil squirter before plunging down with the cutter.
Doh, a mistake I wont make again
Jon

 

ABF cams have more lift and duration as KR cams
https://clubgti.com/forums/index.php?threads/a-vw-16v-camshaft-study.15612

84 x 92,8 = 2056 cc or + 3,6 % extra volume ... and some extra compression always helps...

Pistons come normally with piston pin and the correct rings
(but always check rings for ring gap into bore )