Hey
there fellow z freaks!
I am doing a custom exuast job on my zx. I am buying all the pipes, marking them, and cuting them in my own design. my plan is to leav the cat off, and put a new mufler on, being one of my choice. my question is dose any one think it will start backfiring with the muffler on?

 

dude
I just took my 280zx out to put some more gas in the tank, and noticed that in 2nd, and 3rd she was twiching, or like a sliping filling, but when I hit the gas harder she just squated and and took off faster without that filling. I don't have a miss fire, because I fixed that, is this filling common on slow take offs? if anyone has any ideas thats cool. I can tell you that the transmition is in top shape so I know that it is not the problem, however the clutch has some miles on it, but it looked great when I put the engine in. other than that ever so slight nuging, she takes off like a bat out of hell I mean I have never owned a car that performed like it. she makes me proude.

 

I think I know what you mean. The car jerks a little. That's probably a bad connection on a sensory. Most likely the throttle position sensor.... or maybe you installed a large throttle body? That's a common thing with the 60mm throttle.

anyway, try removing the plug off the throttle position sensor on the side of the throttle body. There are three prongs inside. Clean them with WD-40 and your sister's toothbrush. Let it air dry a few minutes and put it back together.

Just look around the two air tubes on the front. Mainly the one that connects the throttle body to the Air flow meter. (The AFM is that funky silver thing with the black plastic cover on one side) Make sure the connections are snug and there are no holes or cracks in the rubber.

 

I think your right my friend.
sounds like I can give that a try even though I can barely fill the sliping, and I can't finde my sisters tooth brush.
I tell you what man I took the car to the back of my parents property, and gave it a nudge in first, just to see what it would do, whyle I was rounding a curve in the property line, I just started cuting donuts man 1st, 2nd, 3rd, then I let up and cruised up to the front of the land, I could almost think I couldn't be any happier with how she is running. this car is my true baby.

 

...on gravel road?

 

No way man. did it all on my parents property. they have 10 acres. I can only spin the tires up to 2nd on the paved road. even then, they won't spin long in 2nd. she is a nice runer thogh.

 

Very nice - I wish my '81 2+2 would do that ... what size tubing are you using? I was planning on a custom exhaust in the near future - I wanted a 3", but I remember someone at hybridz.org telling me that a 3" was too big unless massive engine upgrades are in the works. For now, my car is NA, but I plan on installing two T25 hairdryers from a couple 1st Gen Eclipses - would I need the 3" then for improved flow? I plan on running a cat and muffler (damn that Utah emissions testing ...), but I would like it as loud as legally possible. And if it pops, farts, and shoots flames, all the better, in my opinion .

 

Well the 3" pipe sounds kind of big, but it might be right. the piping isn't expensive were I live so if I screw up it is no big dill. When you have that cat on there I don't think it will back fire too much, but What I would probably do is look for a high flow cat. As for what size pipes I am cuting I am not sure yet because I am bending them, marking and cuting them all my self so I have to keep in mind that with any bends there needs to be enough clearance. My county dosn't do emisions test so I really lucked out. anyway if you put a high flow cat on there it should be geting good flow through there. I had a friend who took his mustang to a mufler shop, and had them holow out his cats and weld them shut. gave him a lot of powere, and rumble.

 

I had a custom exhaust put on my Z about a month ago. The guy ran it from the back of my MSA header to the back of the car for $80. I had him use 2 1/2 inch pipe and a turbo muffler. I put a dual tip on the back of the muffler and the car sounds bad ***, no popping or backfiring. I gave me a little bit of power on the high end. I haven't taken it to the track yet to see what kind of improvement it actually made. Last time I ran a 10.11 @70.2 mph.

 

None of your exhausts pop when you let off the gas?? i have a msa aluminized exhaust on mine with stock manny and cat and it pops when i decelerate... i love it

 

my 2.5 no cat with borla pops when i let off... it sounds like a rally car i love it too

 

My car pops when I let off the gas on the free way. My stock pipe broke off so I just welded a 2 1/4 pipe on to the stock muffler.

 

she only pops on de exceleration if I keep my foot on the pedle a little. it dose sound good. I took the car out to bowen brown loop the other day, a place down the road from my house. I was giving my big brother a ride, to show him what I had. any way that was the first time in my life I have ever scared him. the road is only barely big enough for two cars and has sharp curves, and is heavely wooded on each side. I took the car as fast as I could down that road untill the tires were squiling around the curves and when they straightened out I hit the gas harder. it was so funny. I did the same thing to my girl friend, but I did that on 2025 when it was raining, and it kind of scared me to.