Capt Mark Posted February 20, 2011 Share Posted February 20, 2011 Ok here is my issue... I bought a short block N42 built by Marc Sayer, performance engineering in 1999 that was wrapped and stored. He put dished pistons in it, but I want to go with flat tops and bump up the compression. To the point… I am having a hard time finding flattops pistons 040 over. Not looking for forged, It should be under 180 hp so cast is fine. Does anyone know who sells them or could you please point me in the right direction? This is my base specs "for now"……(going in a 70/240z) • l2.8 N42 Block flat top pistons punch 1mm over • E88 head w/ mild porting • 1mm head gasket • 270-80F cam grind III • New timing set • N36 intakes ported w/ early z balance tube • 4 screw SU Therapy w/roller bearings, modified jetting, nozzles • 3/2/1- 2.5†Header jet coated w/ new twin tip exhaust • Lighten fly wheel • new clutch, pp and t/o bearing • HEI Points less distributor • Turbo oil pump Thanks for the help, I will take all I can get. Capt Mark ps... I searched pretty hard all day Quote Link to comment Share on other sites More sharing options...
Pharaohabq Posted February 21, 2011 Share Posted February 21, 2011 Might check with an engine builder / Machine shop, Perhaps there are pistons from something other than an L28 that might work. Quote Link to comment Share on other sites More sharing options...
Oddmanout84 Posted February 21, 2011 Share Posted February 21, 2011 Are you sure you want to bump the compression up that high? From my understanding (unless you're running very high octane race gas), using flat tops in addition to a 1mm head gasket and E88 head is going to result in an extremely high and likely unmanageable ratio. What's your current measured CR with the dished pistons? Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted February 21, 2011 Share Posted February 21, 2011 (edited) I am running an e88 head with an F54 flattop block. I have an aggressive cam (.495 lift 290 duration) and I use 91. I think the CR is like a 10:1. Timing is also retarded just a bit and I have 40 webers Edited February 21, 2011 by BluDestiny Quote Link to comment Share on other sites More sharing options...
Capt Mark Posted February 21, 2011 Author Share Posted February 21, 2011 We get 91-93 octane here in Florida and this is a weekend car so gas is not an issue. Attached is the difference with the online calculator. It is just a base starting point, with a 1.27mm gasket drops to 9.88CR. I have friend that did this build w/ stand pistons and it is very strong. Quote Link to comment Share on other sites More sharing options...
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