Bally 4 Posted July 13, 2007 Just ralised that my little 8 valve sleeper is too much fun and has taken my mind off my Mi16 turbo So just went outside and made a plan Tell me what you think. Mi16 alloy Block. Std Mi16 crank- Checked and polished Std Mi16 con rods Std Mi16 lower compression pistons (the one marked X suppose to be 9.?? : 1) All new peugeot Main Bearings, big end bearings, rings, thrust washers and gaskets . Mi16 Head with all valves reseated, ports cleaned up, slight skim Now I have been told on this forum to use two std cams instead of the Kent PT1601 I had in Head gasket is cometic metal gasket, now I have two choices, I have one that is .030" or .051" Which would you suggest. Dont want the compression too low... So tell me what you think and what you would do differently. Share this post Link to post Share on other sites
petert 554 Posted July 13, 2007 Using the 0.051" gasket you'll have around 9.5-9.6:1. I'd still take a small skim off the pistons. Share this post Link to post Share on other sites
Bally 4 Posted July 13, 2007 So even with the low compression I should still use the thicker gasket and still skim the pistons? How much you suggest. Share this post Link to post Share on other sites
petert 554 Posted July 13, 2007 I'm certainly no expect on forced induction, but if it was me, I'd be aiming for 9-9.5:1 max. and 8psi of boost, keeping in mind that the limiting factor is the cast pistons. A thicker gasket is certainly an easy solution, but so is taking a small skim off the top of the piston. Maybe just 0.25mm? Share this post Link to post Share on other sites
Bally 4 Posted July 14, 2007 well i have been running 8 psi someimes ten day in and day out on the high compression with no intercooler and 94 degrees intake temp on std pistons before. Tuning is the key. So i would raher not weaken the pistons, but instead just run the thincker headgasket with the lower compression pistons and the intercooler. Share this post Link to post Share on other sites
petert 554 Posted July 14, 2007 (edited) So i would raher not weaken the pistons, but instead just run the thincker headgasket with the lower compression pistons and the intercooler. Very wise. I still think more than 10psi is flirting with danger. The X pistons already have a thinner crown by approx. 1mm, compared to the Z piston. I did measure it once, at approx. 0.190" thick from memory. Tuning is certainly important and if you can keep it below under 11.5:1 under boost, you'll trade off a little power for reliability. Edited July 14, 2007 by petert Share this post Link to post Share on other sites
James_R 3 Posted July 16, 2007 Could use a 86mm crank pretty common and would drop the compression which would have more of a benificial effect than the loss in capacity. Share this post Link to post Share on other sites
petert 554 Posted July 17, 2007 Could use a 86mm crank pretty common and would drop the compression which would have more of a benificial effect than the loss in capacity. I think that's a very clever solution. According to my calcs., an 83 x 86mm engine, with high compression "Z" pistons, would be 1862cc and 8.5:1 CR. Perfect. You also get the added bonus of the thicker piston crown. Share this post Link to post Share on other sites
whizzer71 0 Posted July 17, 2007 Where does the cometic metal head gasket come from ?,Is this an aftermarket replacement item or one which is used on another pug like the 306 Gti6 for instance ? Cheers Tristan Share this post Link to post Share on other sites
Mandic 0 Posted July 17, 2007 http://www.cometic.com/ Cheers Ziga Share this post Link to post Share on other sites
Hilgie 16 2 Cars Posted July 17, 2007 I think that's a very clever solution. According to my calcs., an 83 x 86mm engine, with high compression "Z" pistons, would be 1862cc and 8.5:1 CR. Perfect. You also get the added bonus of the thicker piston crown. Has been done before...only 'disadvantage' is that the engine is going to be around 1850cc. Otherwise a proper solution. Straight fit as well. Share this post Link to post Share on other sites
Bally 4 Posted July 17, 2007 Only problem is that I can count the Mi16 in Bdos on one hand, and the the S16 on the other, so cranks and stuff are not readily available like that. Share this post Link to post Share on other sites
Hilgie 16 2 Cars Posted July 18, 2007 Any 2.0 crank will do...2.0-8V, S16, 2.08V turbo etc. Share this post Link to post Share on other sites
Hilgie 16 2 Cars Posted July 20, 2007 none none none Those 2.0-8V engines were in a LOT of cars: XM, Xantia, ZX, 406, 306, 405 or are you going to tell me there's none of these cars where you live? Share this post Link to post Share on other sites
Bally 4 Posted August 1, 2007 Peugeots are not very popular and we dont scrap cars here like that. Cars no matter how hard they are hit usually get repaired. Anyhow engine is almost finishd built. Thanks for the help. Share this post Link to post Share on other sites
