M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Swaps, Turbos, Buildups => Topic started by: crazzy_hippo on November 06, 2008, 11:30:54 PM

Title: Help Ordering Custom Pistons!
Post by: crazzy_hippo on November 06, 2008, 11:30:54 PM

Hi guys I need some help ordering custom pistons. Is it necessary to fill in all the details on the forms. What if there are details I don't know about? This is because I am trying to ask wiseco to custom pistons for my engine but I have no idea about some (or rather most) of the details to fill in. Things like deck clearance, valve pocket depth and angle etc.

I have got not idea what are they and how to get the measurement at all.

Btw, I also need some advice/suggestion regarding my engine project. I am trying to build a M42 motor thats similar to MM's design but at a lower price. So far, I have managed to source for a M47 crankshaft, Eagle M50 conrods. Thus all thats left are the pistons. I did thought about using MM pistons but the Eagle rods are longer than the MM rods.

I am planning a compression of 9:1 running 14-15PSI of boost using a supercharger. Do you think this configuration is OK or is the compression too high for the boost?

Thanks!

Title: Help Ordering Custom Pistons!
Post by: 1991 E30 M42 on November 06, 2008, 11:39:22 PM

if you are having issues ordering pistons I don't think you should be trying to build an engine

Title: Help Ordering Custom Pistons!
Post by: crazzy_hippo on November 06, 2008, 11:59:33 PM

Quote from: 1991 E30 M42;60138

if you are having issues ordering pistons I don't think you should be trying to build an engine

I am not building the engine. I am getting someone else to do it. But I need to supply him with the parts.

Title: Help Ordering Custom Pistons!
Post by: asubimmer on November 07, 2008, 01:20:56 AM

Quote from: crazzy_hippo;60137

Do you think this configuration is OK or is the compression too high for the boost?
 
Thanks!

depends on if you have a good tune or not.  You don't need low compression for high boost.  :rolleyes:

Title: Help Ordering Custom Pistons!
Post by: bar73k on November 07, 2008, 02:20:41 AM

i got my pistons made through topend performace, all i needed to supply was what motor they were for, what compression ratio i wanted and what size e.g. standard, or over sized

Title: Help Ordering Custom Pistons!
Post by: crazzy_hippo on November 07, 2008, 11:05:14 PM

Some updates. Wiseco has gotten back to me. This is the reply.

Small resume:
Block M42B18 bore will go from std. 84 to 86.0 mm.
Piston pin 22 mm.
Stroke std. 81 will become 88.0 mm
Compression height  std. 31.65 mm. + 5.00 mm. ( due to the shorter rod)  - 3.50 mm. ( due to the longer stroker) makes CH. 33.15 mm.
Displacement will raise from 449 cc to 511 cc Compression Ratio will go from 10:1 to 9.0:1 so you'll need 14 cc extra volume in the piston dish.
Do you you agree with this layout? Price for a 4 piece kit with rings, pins and a skirt coating will be € 704.20
 
 
Vriendelijke groet / Kind regards.

Title: Help Ordering Custom Pistons!
Post by: crazzy_hippo on November 07, 2008, 11:05:59 PM

Some updates. Wiseco has gotten back to me. This is the reply.

Small resume:
Block M42B18 bore will go from std. 84 to 86.0 mm.
Piston pin 22 mm.
Stroke std. 81 will become 88.0 mm
Compression height  std. 31.65 mm. + 5.00 mm. ( due to the shorter rod)  - 3.50 mm. ( due to the longer stroker) makes CH. 33.15 mm.
Displacement will raise from 449 cc to 511 cc Compression Ratio will go from 10:1 to 9.0:1 so you'll need 14 cc extra volume in the piston dish.
Do you you agree with this layout? Price for a 4 piece kit with rings, pins and a skirt coating will be € 704.20
 
 
Vriendelijke groet / Kind regards.