Stroker Advice

[jules325i]

Building a stroker for a mate who wants to go all out, and make a fast m20 (i know its not cheap)
He is getting the IE 3.0 stroker kit (when they get stock in) and wants it lumpy.
I need some advice as to what compression ratio we should order, combined with 288 camshaft and I'm thinking of getting a the cylinder head from Bimmerheads.

Please give some advice on what else i should do.

[digger]

what does allout mean?

what budget for parts?

[jules325i]

what does allout mean?

what budget?

He will spend about 6k on parts he already has BTB extractors and megasquirt.

[digger]

He will spend about 6k on parts he already has BTB extractors and megasquirt.

6k parts or all up?

[jules325i]

6k parts or all up?

6k all up, he has a new clutch already on his car.
And ill do all his labour for beers.

[digger]

if you want good power then budget for one of ramas ITB kit and a nice basic ported cylinder head that's where you will make power. you wont be able to get a roller rocker setup with that budget. with a 288 you would want 11:1 but you could go a bit bigger cam with ITB as they will tame the 288 alot and bump the CR even further

is it a street car?

[jules325i]

if you want good power then budget for one of ramas ITB kit and a nice basic ported cylinder head that's where you will make power. you wont be able to get a roller rocker setup with that budget. with a 288 you would want 11:1 but you could go a bit bigger with ITB as they will tame the 288 alot

Where can we get ramas ITB's.
Also what cam do you run i noticed your 11:1 did you go with a 3 angle valve job.
As for valve springs is performance double springs better than single.
also i heard a stroker with ross pistons the other day and it had a very audible rattle that he said was normal with forged pistons is this true, or was the bore to piston clearance a little large.

Its a weekend car just for driving pleasure.

[digger]

Where can we get ramas ITB's.
Also what cam do you run i noticed your 11:1 did you go with a 3 angle valve job.
As for valve springs is performance double springs better than single.
also i heard a stroker with ross pistons the other day and it had a very audible rattle that he said was normal with forged pistons is this true, or was the bore to piston clearance a little large.

i run a catcam 298/285 but would try a non split cam like a schrick 288/288 if i was to swap in another it has a little less intake duration, a little more exhaust duration and tighter lobe centers. you want a nice valve job and some massaging of port short side, guide area and blend the bowls to the seat to help keep the head flow stable but not much material removed to keep velocity up

www.racehead.com.au he can also do a basic port job for you ( he has a flow bench and nice setup for various valve jobs) and is in Sydney i would ring him he does quite a bit of m20 stuff these days

forged pistons can rattle when cold they need more clearance than a cast piston in general but the clearance depends on the application and some piston manufacturers ask for more clearance than others.

double springs are fine as are a good single beehive. with 288 just a light upgrade is ok some i think even use just new stock ones but i would get slightly uprated ones. you dont need fancy retainers to save cost

[nando]

the rattle depends on how the forged alloys were made. I think they add silicone to get rid of the rattle (they expand less, so you can run tighter clearances), but it makes them a bit more brittle. that said I've put tens of thousands of miles on my MM pistons (wiseco manufactures them), and have never heard a peep. I don't think the extra brittleness makes much difference on a street, N/A application.

[jules325i]

i run a catcam 298/285 but would try a non split cam like a schrick 288/288 if i was to swap in another it has a little less intake duration, a little more exhaust duration and tighter lobe centers. you want a nice valve job and some massaging of port short side, guide area and blend the bowls to the seat to help keep the head flow stable but not much material removed to keep velocity up

www.racehead.com.au he can also do a basic port job for you ( he has a flow bench and nice setup for various valve jobs) and is in Sydney i would ring him he does quite a bit of m20 stuff these days

forged pistons can rattle when cold they need more clearance than a cast piston in general but the clearance depends on the application and some piston manufacturers ask for more clearance than others.

double springs are fine as are a good single beehive. with 288 just a light upgrade is ok some i think even use just new stock ones but i would get slightly uprated ones. you dont need fancy retainers to save cost

Very helpful.
Thankyou.

[digger]

it might be easier to get it up and running on the factory manifold to start with etc

[jules325i]

it might be easier to get it up and running on the factory manifold to start with etc

Yeah true,
Um do raceheads sell those itb kits (is it the 40mm kit?)
This may be a stupid question but where does the Bitch tube go and the injectors with those itb's.

[digger]

Yeah true,
Um do raceheads sell those itb kits (is it the 40mm kit?)
This may be a stupid question but where does the Bitch tube go and the injectors with those itb's.

can also do 42, 45 and 48 but 40 or 42 will be plenty

he is developing a CNC manifold that has the recess for bitch tube which bolts between the head and ITB. currently he cuts up a stock manifold and keeps the first few inches and welds on a flange with DCOE pattern

http://www.e30tech.com/forum/showthread.php?t=118357

http://www.e30tech.com/forum/showthread.php?t=117701

[jules325i]

can also do 42, 45 and 48 but 40 or 42 will be plenty

he is developing a CNC manifold that has the recess for bitch tube which bolts between the head and ITB. currently he cuts up a stock manifold and keeps the first few inches and welds on a flange with DCOE pattern

http://www.e30tech.com/forum/showthread.php?t=118357

http://www.e30tech.com/forum/showthread.php?t=117701

oh i see,
Those threads are awesome huge power from that e21.
And beautiful ITB setup.

[SkiFree]

the rattle depends on how the forged alloys were made. I think they add silicone to get rid of the rattle (they expand less, so you can run tighter clearances)

And it should also be mentioned that the rattle associated with with higher expanding pistons dissapears once the engine is warmed up (and the pistons expand to the walls). Pretty standard procedure for a higher strength piston.