Hey just wanted a bit of advice in modding my 91 civic with D15b motor. I am currently rebuilding the engine and thought shaving the head wuold be a good way to make some power. I guess id want about 10.5:1 compression, is this a safe amount running AUS premium petrol.Any1 know how much exactly id have to take off and how much power i could expect. Also was gonna do a few thing on the carb, cutting the springs and shaving 1mm of where the piston goes up. Does this make much power?? What would be the best option to run a pod filter down to the front of the car from the air intake pipe and remove the filter in the box or to take that off the box and just have 2 of those motor bike filter hangin off the carbi?? With all these mods i just wanted to get some opinions and estimates of horse power gains and if someone has anything to add an easy way of making some power please let me know thanks in advance

 

can any1 help?

 

Ok, to reach 10.5:1 you will be removing an unsafe amount of material in the mating surface, therefor causing ever so nice valve-piston slappage. What I would recommend is a 0.030" mill and an oem headgasket of the D16Y8 motor. That will give you 9.9:1. This is assuming though that your stock compression is 9.2:1 and with clean combustion chambers etc. etc. If you want to go higher you will have to either change the head out or change the pistons.

With the carbs, I know there is a gentleman around here from Kuala Lumpur building up a D15 Carb, and his name is nickgomez.