I got a 90 teg wit a cheap hp racing imitation n1 muffler.when driving, especially on the highway when I let off the gas the car draws back slowing down dramatically.
i have 18" resonator 2.25 piping catback, generic 4-2-1 header.
im wondering if ... i advance the timing will it flow a bit better, or the custom bending @ the axel is ceating a bottle neck, or "you get what you pay for" applyz to my situation? TIA



[Modified by DonDADA, 4:20 PM 2/10/2003]

 

you want it to give up the rpm's as quick as possible.

 

Well, I'm sure that your cheap muffler sounds like crap, but I wouldn't forsee that it would cause you to lose any horsepower, or gain any for that matter. It's sounding to me like it's just a noise maker. You did at least upgrade your piping, but 2.25 might not be big enough, but then again it might be ok. There's a great debate surrounding this. The one side says that for a 1.8 liter engine, 2.25" piping is plenty big. It will reduce backpressure while not letting you lose some of the needed backpressure. Too little backpressure will reduce horsepower. On the other hand, there are some who think that the 2.25" piping is simply too small to adequately reduce back pressure enough to free up any power. They believe that the 2.5" is the way to go. I have 2.5" on my RS. I have never dynoed it though, plus I have a header and a modified intake setup.

As far as advancing the timing, I wouldn't screw with it unless either A) you know what you are doing, or B) you take the car to somepne who does. I doubt that will make too much of a difference in and of itself.


[Modified by 4doorRS5spd, 7:41 PM 2/10/2003]

 

There's really no way you lost power. You probably just didn't gain that much.

 

true

 

 

does your throttle feel more responsive on the highway?

i put on a I/H/E and could deff feel the diff in the mid range when accelerating or dumping the gas, feels like pulling the parking brake up


[Modified by dpo95si, 12:19 AM 2/11/2003]

 

on the highway i dont feel the responsiveness.just rough acelleration thru the exhaust. if im doin bout a 100km 3rpms ,if i gas it the exhaust makes a **** full of noise rpms move really slow, then when it gets to 4.5 rpm it starts to move and the car tops out at 160kms i cant get no faster!! WTF HELP!

 

sell it