Clearance issues with stroker cranks.

[validius]

I've been researching different stroker configurations since i now have a spare M20 sitting on a stand. I'm reading conflicting reports.

What i know for sure:

• ETA crank clears without modification.
• Dual VANOS crank needs modification to clear.

What i'm getting conflicting reports on however is if an early M52 crank will require piston and block clearance work. According to this, it should work factory. I've read in places on r3v though that indicate that the cranks available in North America will always require clearance work.
I've never attempted an engine build before and i have no sense of how much work/cost it is to modify piston skirts and have the assemblies balanced. Does this have effects on durability? There is a decent machine shop where i work so making the spacer is not a big deal.

Finally, i'm interested in opinions on if it is worth the hassle over putting an ETA crank in. I want to build a street motor for my convertible. The intent is to drop the rear end ratio down to 3.25:1 or less. I find the stock setup to be a bit buzzy. The car is intended to be a GT car that is enjoyed most at 55-60MPH on back roads. Superior low end is the goal though i would obviously prefer not to loose anything up high over stock if possible.

[digger]

I've been researching different stroker configurations since i now have a spare M20 sitting on a stand. I'm reading conflicting reports.

What i know for sure:

• ETA crank clears without modification.
• Dual VANOS crank needs modification to clear.

What i'm getting conflicting reports on however is if an early M52 crank will require piston and block clearance work. According to this, it should work factory. I've read in places on r3v though that indicate that the cranks available in North America will always require clearance work.
I've never attempted an engine build before and i have no sense of how much work/cost it is to modify piston skirts and have the assemblies balanced. Does this have effects on durability? There is a decent machine shop where i work so making the spacer is not a big deal.

Finally, i'm interested in opinions on if it is worth the hassle over putting an ETA crank in. I want to build a street motor for my convertible. The intent is to drop the rear end ratio down to 3.25:1 or less. I find the stock setup to be a bit buzzy. The car is intended to be a GT car that is enjoyed most at 55-60MPH on back roads. Superior low end is the goal though i would obviously prefer not to loose anything up high over stock if possible.

those cranks are not really found in the USA (or are atleast as rare as rocking horse shit) they seem to be found in "europe and the like" on euro spec for lack of better term. i imported an early one from USA to Oz and it was a big C/W version. so i would work on clearancing being needed with the big counterweight version. making it fit wont compromise anything to a degree worth worrying about provided the workmanship is good. for example a proper re-balance after the crank counterweights are reduced etc.
i personally am not a huge fan on hacking the bottom of piston bosses below the existing boss radius (dont go under 5mm wall thickness in pin boss) so this means modifying the skirt alone is not an option modifying the crank is also needed to, but i know others have done it differently and it works well for them.

there wont be much deficit between eta style 885 build over the 885 style b28 crank i would say 5-10hp. the eta build requires decking a fair bit (2mm) off the block to use the correct b25 piston compared to 0.5mm for the b28 crank nominally

[validius]

those cranks are not really found in the USA (or are atleast as rare as rocking horse shit) they seem to be found in "europe and the like" on euro spec for lack of better term.

Perhaps it might be worth checking out German Ebay?

[SkiFree]

If you want good durability and a very healthy torque curve, then consider ponying up for the IE/Mahle Street Stroker pistons. They were designed to be the ideal street performance setup.

http://www.iemotorsport.com/bmw/E30-engine/M20B29mmiepistons.html

http://www.r3vlimited.com/board/showthread.php?t=211891&page=19

[digger]

Perhaps it might be worth checking out German Ebay?

could be a bit of stuffing around trying to make sure what you buy is the correct one then paying shipping for a 25kg bit of steel in a box. E30Zone forums could be a good option most people on there would know the correct version not like a random of ebay