N1 dual rubbing drive line

[jrc90240sx]

Ok this one is just kinda buggin me. my N1 dual is rubbing my drive line, it makes a scratchy sound all the time. and there is a clean line on my drive line were the resonator (houseing around the Y pipe) is. I think that it might just be to warn out engine and transmission monts but just wanted to hear what you all might have in mind. and any posable fix. thanks

Joe

[MikeS14240sx]

What model year is it on? I've heard people say that on the m/c s14's that the piping rubs on the diff. but i have the dual n1 on my 98 and there is plenty of room and it has never rubbed. Sounds like you may have warn out transmission or engine mounts like you said.

[jrc90240sx]

It is a 90. When parked and the car off, there is about 1-1.5". It only seems to rub when in lower RPM band, when I am trying to accelerate. Well I was already planning on swapping my mounts when I do my SR swap, just starting to worrying things aren’t going to hold together tell then.

[MaineExport]

That's strange.... I can see if we had a solid/live axle in the rear, that it would drop under accelleration... actually... the torsion would tend to lift the differential instead of dropping it. But since our rear diff is in a fixed location the drive shaft shouldn't be able to drop an inch or more... that is really strange. Is it rubbing down near the diff.?... on the s14 the only time the pipes are close to the driveshaft is about 2 inches before the diff. I would think that the engine mounts are the only explaination... but the engine/transmission would have to drop a LOT in order for the driveshaft to drop an inch in the rear. It is a pretty wierd setup.. the cat is attached to the transmission via a cross brace (s14)..... that would drag your exhaust down WITH the transmission/driveshaft... as I was hauling on my stock exhaust to rip it out.... I noticed my transmission and driveshaft moving along with the exhaust... totally freaked me out at first, until I figured out why. Very proplexing situation....

[SpeedRacer1]

Yeah I guess the 90's N1 is kinda close to the drive shaft. Did you check to see if the bolt holding the premuffler up in the back is still tight? If it were loose I could see the exhaust moving under certain loads.

[jrc90240sx]

All the bolts are tight from the engine back. what i think is happening is when there is a load on the engine it will lean to the exhaust side of the engine to much. when this happens the exhaust moves with it, moving it into the drive shaft. witch would mean my mounts are worn out. kinda sucks, i guess I will just have to leave with it for 4-5 months tell i swap to the SR. thanks for the input

Joe

[SpeedRacer1]

Yeah im not sure about the KA leaning when you drive hard, Ive got an SR.

[jrc90240sx]

Well just about any engine will want to turn when you give it gas. the engine monts hold it in place keeping it from turning around in a circle. I understand that you most likely know this, your last reply just didnt sound like it. the engine turns in a clock wise motion, causing the motor to lean to the exhaust side of the engine or right side if your looking at it from the front. the transmission will rotate also clock wise, the drive shaft really wont move because it is the rotating axis. the exhaust being connected to the engine will also rotate, makeing it move toward the driver shaft. Any engine will want to rotate, with out the engine mounts it would, if they are warn out they will alow the engine to rotate more then it would normaly. this makes the engine loss some power on take off, or under load. that is why new stiffer engine mounts get you a better 60ft time. hope that clears anything up, and if you already know this sorry for the recap.

Joe

[SpeedRacer1]

Yeah but from what I hear the KA is less balanced than the SR and I think would tend to move more under lower loads.

[MikeS14240sx]

It doesn't matter how the engine is balanced. Once the motor mounts wear out the engine will have more rotational movement under any load. Try reving the engine by the throttle body or have someone else rev the engine and watch to see if the engine rocks a lot or makes a thud sound why'll reving it up, this will tell if its a warn out mount.