sgtjackass Posted October 18, 2009 Share Posted October 18, 2009 Hi guys, you may be able to help me with a non honda specific inquiry. My car is running very well but 'pops' alot during deceleration (sp?). Even if i give the throttle a small stab at idle it will rev then pop. I have seen it at night and these pops light up the tailpipe pretty well. Now im not worried about the popping, or the fire out the pipe, what i am interested in is: 1) Are these pops indicative/ a symptom of poor tuning ie timing ect? The reason i ask is because the car feels a little strangled, like it should and could be faster. 140hp in a 800kg car should be pretty lethal, yet sometimes It feels a little lethargic. Compressions are spot on, plugs look fine and fuel economy is unbelivabley good. The other question i have relates to exhaust backpressure. The car currently has very little in the way of exhaust. It has a 2 1/4" pipe with 2 short coby resonators. It is loud to the point where ear muffs are almost needed on long trips. Obviously this is not ideal as it draws attention (not good when your driving a bright yellow crx) so will be changed. The guy at pitstop was all like 'yea those twin cam zc's love a bit of backpressure, you need this (points to a restrictive $200 dollar muffler destined for a holden of some sort)' 2) By putting in a more restrictive muffler, and therfore by increasing backpressure, am I likely to gain any HP? Sorry this is a bit long winded, but im no engineer. Cheers Quote Link to comment Share on other sites More sharing options...
Unclejake Posted October 19, 2009 Share Posted October 19, 2009 If you put a more baffled exhaust on it there is a high likelihood your overrun exhaust pop will dissapear. In an otherwise un-modified car retarded ignition timing or too little exhaust backpressure will cause the pop. Loud exhausts are for boy racers who don't give a shit about the rest of the world and you don't want to be confused for one of them Quote Link to comment Share on other sites More sharing options...
My name is Russell Posted October 19, 2009 Share Posted October 19, 2009 Sounds to me (or though i have limited tuning knowlege) the engine is running rich and will run quicker leaned out also stop dumping fuel out the exaust. My escort was doing the same for ages until i put a new engine in with same carb i bothered changing the fuel ratio and it went away straight away. And save fuel Oops just read UJ's reply again, yeah i would start with a muffler. Quote Link to comment Share on other sites More sharing options...
kpr Posted October 19, 2009 Share Posted October 19, 2009 hmm these must not have over run fuel cut(injectors switch off on overrun) or it is not working. as wouldn't be any pops if there was over run cut. possibly tps related. if its actually spose to have a cut. i no nothing about honda specific stuff though. +1 changing exhaust as well. but more back pressure wont gain you hp. thats something mr pit stop pulled out his ass. Quote Link to comment Share on other sites More sharing options...
cubastreet Posted October 20, 2009 Share Posted October 20, 2009 +1 for pitstop guys ass. if your pipes are too fat you lose power as the exhaust gases flow slower -> less scavenging. reducing diameter to optimum will increase power but not due to backpressure. don't know what optimum is for your motor but someone here probably will. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.