Ok.. I have the A'PEXi N1. Have had it for like a year and a half now. About a month or so ago it's gotten very raspy when I hit around 4000 rpm's. It use to be only under WOT, now it sometimes gets super raspy when not even in WOT. Some days it does it more than others.

I just put tinfoil over the end of my exhaust, taped the bitch down (had a small leak that let some of the air out but not much) and felt around the joints, flex-pipe, and header to head point... felt *nothing*.

Anyone have *any* clue why this would happen out of no where like that? I do have a gutted cat, but it's been that way for quite some time now. Could a screwed up adjustment on an exhaust valve cause super bad exhaust pulses making it raspy like that? Thanks in advance for *any* advice!

 

You most likely have an exhaust leak somewhere. I really lost you on the whole tinfoil deal but where you trying to find an exhaust leak that way???

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GudeH23a &raquo;</TD></TR><TR><TD CLASS="quote">You most likely have an exhaust leak somewhere. I really lost you on the whole tinfoil deal but where you trying to find an exhaust leak that way???</TD></TR></TABLE>

Yeah, i used a sheet of heavy duty renolds wrap plus some tape to cover the tip of the N1 to build up the pressure. No luck! No leak felt anywhere... I'm really stumped I can't get on it because it seriously sounds like a **** exhaust on a civic!

So my question is.. I know I have a server tap/knock on the upper end.. sounds like the exhaust cam about 3" in from the distrubutor. Could this "valve" issue be the source of my whole problem?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rjr162 &raquo;</TD></TR><TR><TD CLASS="quote">

Yeah, i used a sheet of heavy duty renolds wrap plus some tape to cover the tip of the N1 to build up the pressure. No luck! No leak felt anywhere... I'm really stumped I can't get on it because it seriously sounds like a **** exhaust on a civic!

So my question is.. I know I have a server tap/knock on the upper end.. sounds like the exhaust cam about 3" in from the distrubutor. Could this "valve" issue be the source of my whole problem?</TD></TR></TABLE>

doubtful but hey why dontcha get a valve adjustment anyways it sounds like you need one.

I welded an N1 tip onto my greddy system and I have the same issue. I just chalked it up to the fact that an N1 can has minimal resonation material compared to say a big greddy can so after a year or so it doesn't do much good except get raspy

 

Thanks! I was thinking it was the canister... I know the JUN universal doesn't come down to the correct size tubing to meet up the with N1's catback exactly... but I think I may get it and give it a shot... that or the RollHard.. see if that clears things up a bit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rjr162 &raquo;</TD></TR><TR><TD CLASS="quote">Thanks! I was thinking it was the canister... I know the JUN universal doesn't come down to the correct size tubing to meet up the with N1's catback exactly... but I think I may get it and give it a shot... that or the RollHard.. see if that clears things up a bit.</TD></TR></TABLE>

I think the material they are using is just worn out. I know greddy uses like stainless wool and some other crap to make it last longer.

 

not only that, but N1 is very very thin compared to the standard walls of most mufflers: This gives that raspy sound, one reason why every generic walmart/cherry bomb style muffler sucks , is that they go too cheap and it just vibrates at those high RPM's


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by satan_srv &raquo;</TD></TR><TR><TD CLASS="quote">

I think the material they are using is just worn out. I know greddy uses like stainless wool and some other crap to make it last longer.</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by satan_srv &raquo;</TD></TR><TR><TD CLASS="quote">

I think the material they are using is just worn out. I know greddy uses like stainless wool and some other crap to make it last longer.</TD></TR></TABLE>

So do you think it's just the canister at the end, or could the pre-muffler job be the source of the problem? I've always wondered about the way the N1 angles if it would cause problems with rain collecting or not....

 

well no ****.. get this. Car started to misfire extremely today with anything more than half throttle, and got worse after I left work. Figured it had to be a sparkplug or two again (happened once before quite a few thousand miles ago). Changed 'em out because they didn't look too health anymore (NGK V-Power's).... the damn rasp is back to the normal N1 sound. I guess it was a sign of a spark plug starting to fail, or atleast that seems to be the case at this point... isn't that just weird.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rjr162 &raquo;</TD></TR><TR><TD CLASS="quote">well no ****.. get this. Car started to misfire extremely today with anything more than half throttle, and got worse after I left work. Figured it had to be a sparkplug or two again (happened once before quite a few thousand miles ago). Changed 'em out because they didn't look too health anymore (NGK V-Power's).... the damn rasp is back to the normal N1 sound. I guess it was a sign of a spark plug starting to fail, or atleast that seems to be the case at this point... isn't that just weird.</TD></TR></TABLE>

I guess you were creating a harmonic vibration of some sort. Interesting. makes me think mine sounds like that cause of the rough cams.