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DISCUSSION => Swaps, Turbos, Buildups => Topic started by: vatos_p on May 23, 2007, 01:24:22 AM

Title: m42 forged pistons for turbo application
Post by: vatos_p on May 23, 2007, 01:24:22 AM

can someone fill out the following , so we know what exactly should we buy ...
thank you for your help ....

custom pistons order !! ( je )
Type of Use: Turbocharged     
Desired Compression Ratio: 9.0:1 ( is this ok ? for 1,2 bar press or will i need 8,5:1 )   
Desired Finished Bore Size: ?   
Crankshaft Stroke: ?   
Head Gasket Thickness: stock ( ? can we use stock thickness if we drop the pressure from the pistons ? )   
Car Make, Model, Year: 1991
Engine Type and Designation: 318is M42 europe   
Displacement and # of Cylinders:1796 , 4 cyl ( ? )    
Misc.Info:Is it a stroker ? Different Rod Length ? Etc.    
Ring Configuration: Valve Reliefs: Floater or press fit wrist pins: Wrist pin diameter:

anything you know it would be very helpfull

Title: m42 forged pistons for turbo application
Post by: kowalski on May 23, 2007, 08:58:26 AM

http://www.bgsoflex.com/cr.html

* Cylinder head Volume (CC) = 34.00
* Piston Top Volume (CC) = 0.30
* Cylinder Bore (Inches) = 3.4
* Cylinder Stroke (Inches) = 3.46
* Deck Height (Inches) = 0.030
* Head Gasket Thickness (Inches) = 0.068

that gave me 11.7 compression. You will need to figure out what kind of headgasket your getting, right now its set at stock. stroke is set for 88mm, cylinder head volume is stock, piston bore is 87mm, not stock.
http://www.digitaldutch.com/unitconverter/