building a 24v DOHC engine

[Massive Lee]

care to elaborate?

People who are serious about such project (and have the technical knowledge to achieve it) don't post questions as the ones you just asked. Lots of wishfull thinking and particularly no clear direction.

Sorry for bringing the bad news. What's your background that makes you think you can build a 500hp motor with 10:1 pistons, with race cam and loppy idle, with MS but not on start-up? Why are you scared of engine management

[dpgrand]

i love these threads!

[mentaleeill]

i meant just to start with a m52, use its crank and get custom rods and pistons. want to keep the bore as small as possible to keep material between the cylinders on boosted engines for headgasket sealing. so look on bfc and there are plenty of people with their rod and piston specs posted.

[lifeiskaos]

People who are serious about such project (and have the technical knowledge to achieve it) don't post questions as the ones you just asked. Lots of wishfull thinking and particularly no clear direction.

Sorry for bringing the bad news. What's your background that makes you think you can build a 500hp motor with 10:1 pistons, with race cam and loppy idle, with MS but not on start-up? Why are you scared of engine management

i am very serious about this project. do you think some people are born with such knowledge? im sorry for trying to learn? no clear direction, shall i quote myself?

my background has been working with cars all my life, building several engines, tuning experience with megasquirt. i said i want lower than 10:1 comp pistons. i asked for specific advice, not your opinion. if you have nothing helpful to share, please gtfo

i love these threads!

hooray!

[dpgrand]

hooray!

My sarcasm apparently was not noticed. +1 on bimmerforums though.

[Kerrath]

My sarcasm apparently was not noticed. +1 on bimmerforums though.

You're cool.

[SpecM]

Epic thread!

I say m50nv block, s52b32/m54b30 crank, and 84mm (85mm tops) pistons

strong block, long stroke, and narrow bore for more sealing

[lifeiskaos]

Epic thread!

I say m50nv block, s52b32/m54b30 crank, and 84mm (85mm tops) pistons

strong block, long stroke, and narrow bore for more sealing

why is an m50nv block any stronger than a vanos m52 or an m52 block?

[kronus]

^^ the cylinder walls are thicker and can take more pressure

[Kerrath]

^^ the cylinder walls are thicker and can take more pressure

Even after he bores them to 2.9L?

[lifeiskaos]

hmm. interesting. so, starting with an m50 block, what would i do for the cams/head?

[SpecM]

just use a s52 head

[lifeiskaos]

just use a s52 head

options are m50nv, m50 vanos, or m52 head. cams and valve will likely change so it doesnt matter a whole lot

[SpecM]

options are m50nv, m50 vanos, or m52 head. cams and valve will likely change so it doesnt matter a whole lot

m52
same head as an s52, minus cams/springs/retainers

[lifeiskaos]

m52
same head as an s52, minus cams/springs/retainers

sounds good. no one has mentioned rods. lets say im going to use an s50 crank. which rods should i use? pistons will probably be custom low comp 1mm overbore