ok so im a noob when it comes to smog. i want to BAR a gsr in my crx and im going us spec on everything to get it bar'd then mod it. but i dont want to have to tear apart the block all over again and buy new bearings and everything just to install pistons and rods when i can do it on the first rebuild. anywho my question is if i buy some low comp pistons is this going to effect my emissions to the point of me not passing smog/bar. also if this thread is in the wrong forum let me know and i will let the MOD know and have them move it. thank you in advance
-kyle

 

ttt

 

What year/make/model is your vehicle ?
What engine management do you plan on running ?
What tests are performed besides an exhaust sniffer for your vehicle ?

 

i have a 1990 crx si with a usdm 1995 gsr im rebuilding. i was just going to bar the car with the gsr no supercharger or anything just after market pistons for my later mods. im not 100% on what tests are done in baring a car except sniffer and visual. visual should be no prob. i was just wondering if i can pass the sniffer

 

up

 

anyone?

 

If you raise the compression your NOx may increase from increased pressure and heat. If you lower the compression your HC and CO may increase since the fuel wont be burned as efficiently.

You will need a matching USDM ECU, OBD1 conversion, and all smog equipment from the 95 Integra.

 

thank you so much for the input. yeah i have the smog stuff i just need the ecu. shouldnt be to hard to find tho. p72's everywhere =P

so when supercharging my car would low comp pistons be the best choice for me?

 

Low compression is safer for forced induction, and the GSR has pretty high compression for a stock motor. I'm not a professional tuner but in very general terms, given the choice I'd rather have an average stock compression ratio and less boost, vs lowering the compression a great deal and going with very high boost.

Engine management / careful tuning is absolutely critical. You can get more and better power, better street-ability, and better reliability with a carefully tuned standalone (ie AEM EMS) than you can with any tuning setup based on the factory hardware. I suggest prioritizing your budget there and less toward bling and go-fast parts.

 

technically yes, but u dont have to unless u plan on running a large amount of boost. Dont go High Compression though.

 

im not worrying about bling go fast parts right now. im more focused on getting the car bar'd i just didnt want to tear apart the block again after a rebuild to change out pistons and rods. but yeah i know tuning is key. and thank you so much for all the input