SR20 Forum banner
1 - 20 of 22 Posts

·
Registered
Joined
·
106 Posts
Discussion Starter · #1 ·
thanks
 

·
P10 Geek
Joined
·
1,565 Posts
Ferdie Dela Cruz said:
From what i remember from the dealer telling me. They said 1 7/8 in I.D.
Yeah, where it's straight. Then there are the bends, crush bends. They would be closer to 1" depending on how severe the bends are.

There isn't really a true I.D. to go by on the stock piping due to the crush bends used when manufacturing the pipes.
 

·
Registered
Joined
·
4,465 Posts
CRUSH BENDS????!!!!
I redid my stock exhaust and it was all mendrel bent.
94 SE-R.
hmmmmm. :confused:
 

·
P10 Geek
Joined
·
1,565 Posts
SmoothDaddyFig said:
CRUSH BENDS????!!!!
I redid my stock exhaust and it was all mendrel bent.
94 SE-R.
hmmmmm. :confused:
The factory exhaust is not mandrel bend, unless I missed something. Auto manufacturers do not generally offer mandrel oem exhausts because it is easier to make crush bends, less time consuming and of course extremely cost effective for them

Here is the I.D. of the stock OEM pipes on a 200SX SE-R. I will assume that is not very different than your 94 SE-R:

Starting with the b-pipe at the catalytic converter:
1.800" inside
1.918" outside
2.151" middle, before resonator
3.447" the resonator
1.696" before 1st bend
1.540" @ the 1st bend
1.696" before 2nd bend
1.542" @ 2nd bend
1.684" before 3rd bend
1.553" @ 3rd bend
1.692" before 4th bend
1.562" @ 4th bend
1.667" before final bend
1.519" last bend before pipe enters muffler

There is more info on stock piping here:
http://www.geocities.com/n_dahi/exhaust/exhaust.htm
 

·
Registered
Joined
·
4,465 Posts
Dude,

I swear on my life, that I had mandrel bends. I know cause I was down there for like 3 days trying to get the damn catalytic bolts off. I think I still have the stock resonator with a piece of bent pipe in my trunk. ( hee hee!! ) I will take a look on my lunch break.
As well as toss it out. (damn:D )
 

·
Registered
Joined
·
4,465 Posts
Alright, I just got back from my wonderful "CHUNKY" soup lunch and I looked at both my exhaust and the one under someones 91 XE. They are both mandrel bent. I dont know what gives, but, thats that.
 

·
P10 Geek
Joined
·
1,565 Posts
Ok. I just had a custom Borla exhaust installed on my '96 G20 a few months ago, I use to own a '91 NX2000 and had a Borla rear section with custom 2" cat-back pipe, my wife had a '91 Sentra SE and I had to replace the rear section with OEM exhaust and muffler when it rusted away and I also saw JACEN99SE's exhaust sitting in his garage from his '99 Sentra SE after he had a Courtesy midpipe and custom rear section installed.

All of the above Nissan/Infiniti's do have crush bent OEM exhausts directly from the manufacturer.

As well as my '81 Toyota Corolla 1.8 SR-5 Hardtop Sport Coupe
(My first car back in '88. Wish I still had that one.)
and my '84.5 Ford Escort Hatchback
(2nd car)
and my '87 Nissan Sentra SE
(3rd car)

SmoothDaddyFig said:
Alright...
...I looked at both my exhaust and the one under someones 91 XE. They are both mandrel bent. I dont know what gives, but, thats that.
This was bugging me, so I brought it up on the G20.net forum. This is what they also agreed to. See here:

http://www.automotiveforums.com/vbulletin/t9524.html

So, I guess I'm not missing something.
 

·
Premium Member
Joined
·
11,741 Posts
yo smooooooth, lemme know if you still have the stock exhaust, i was thinking of getting one and putting it on when i made the trip from tallahassee to fort lauderdale, the loudness gets to me....6 straight hours of EXHAUST noise!!:D
 
G

·
mine was mandrel bent

I just installed a pace setter exhaust on my 93 se-r and the pipes I removed WERE mandrel bent. My car does have 113k miles on it and the pipes seemed bigger than what I thought they would be ( slightly smaller than the pace setter) so it could have already had aftermarket pipes--but I doubt it. And yes I can tell the difference between the 2. And why do you say that mandrel bends are too expensive from the oem? I bought my pace setter cat back complete mandrel bent for 140 shipped---that puts cost to pacesetter at less than 80 dollars--which would make oem even less than that. Who knows? not that big of a deal anyways--just thought I would add my comments in since I was surprised myself when the oem exhaust came off. The factory exhaust manifold was also very high quality and not very restrictive at all. Maybe nissan does put more money (r+d) into exhaust sytems? Remember the new maximas and altimas have that flapper in the muffler for extra top end?
 

·
Registered
Joined
·
312 Posts
just a side on a side note.... The WRX does have mandrel bent exhaust from the factory. Kinda intersesting. I didn't believe my roommate until i saw it but it is. So yes oem's do use mandrel bends sometimes.

just thought i'd let everyone know.
Rick
 

·
P10 Geek
Joined
·
1,565 Posts
Re: mine was mandrel bent

massclassic said:
I just installed a pace setter exhaust on my 93 se-r and the pipes I removed WERE mandrel bent.
The factory pipes on your Sentra when it came from the factory were crush bent. The types of pipe bends that manufacturers use are smoother than your typical Midas type shops. So you will not see the possible creases in the pipes and therefore it looks mandrel. But it is not. It is just a smoother transitional crush bend.

I bought my pace setter cat back complete mandrel bent for 140 shipped---that puts cost to pacesetter at less than 80 dollars--which would make oem even less than that.
Current OEM Prices for a '91-'94 Sentre SE-R (www.nissanparts.cc)
Exhaust Pipe: $134.11 (20030-58Y00)
Muffler: $112.49 (20100-58Y01)
Misc: $ 15.00 (gaskets, etc)
Shipping: $ 24.66 (UPS Ground)
Est. Total $286.26

I am probably missing some parts on this. ??

As far as the PaceSetter cat-back goes. It has been stated several times by many that the Pacesetter muffler, NOT the piping is poorly manufactured and will rust out in a very short amount of time. You could probably search the forum and all other automotive forums and get the same reply that the muffler, NOT the piping is of poor craftsmanship and the material used will corrode/rust very quickly. Most will replace the rear section with a different muffler but keep the mid-pipe since it is a larger diameter and is mandrel bent and seems to last much longer.

That would be why the price of the Pacesetter is such a great deal.
 

·
P10 Geek
Joined
·
1,565 Posts
Rocketman said:
just a side on a side note.... The WRX does have mandrel bent exhaust from the factory. Kinda intersesting. I didn't believe my roommate until i saw it but it is. So yes oem's do use mandrel bends sometimes.

just thought i'd let everyone know.
Rick
I would agree. Actually, in recent years more manufacturers are starting to use mandrel bends. Most of the cars getting the mandrel bends are more performance oriented cars. I should have mentioned that from my knowledge, most manufacturers between 1981 and 1999 use crush bends including Nissan/Infiniti. I do believe the Corvette with the Titanium exhaust is mandrel bend as well.

As a side note: Borla is now offering the Titanium exhaustsas well.

Bet those aren't cheap!
 

·
Registered
Joined
·
4,465 Posts
Ok somebody enlighten me here.

heres is what I think a cruch pipe looks like:
Its like a crinkled bend, with obvious wrinkles where it was bent.

here what i think a mandrel bend is:
a smooth flowing bend with ABSOLUTELY no crinkles or wrinkles.
and the diameter does get a bit smaller as it bends, but then its back to normal.

I have endangered my life peeking under peoples cars at a time of turmoil, and here in Florida every 91-94 Sentra has mandrel bent pipes. SE-R, XE , SE.................

What gives?!

NismoPC,
This is an interesting discussion and Im going bonkers!!
I saw the post you posted on the other forum. If Im wrong, I too will admit it with no prob. But from what I have seen under like 5 cars , its mandrel to me.
 

·
Premium Member
Joined
·
11,741 Posts
from what i know its a bend where the pipe doesnt change in diameter, just smooth bends. examples below.







you get the idea...
 

·
Registered
Joined
·
4,465 Posts
Damn!!!! That exhaust is tight!!!!!
Okay, SO I WAS WRONG!!!!!
IM BOWING MY HEAD IN SHAME.:eek:
But I have seen worse bends then the stock Nissan ones.

But now I know. "And knowing is half the battle" ;)
 

·
P10 Geek
Joined
·
1,565 Posts
SmoothDaddyFig said:
What gives?!

NismoPC,
This is an interesting discussion and Im going bonkers!!
I saw the post you posted on the other forum. If Im wrong, I too will admit it with no prob. But from what I have seen under like 5 cars , its mandrel to me.
Hehehe! It's annoyingly fun, isn't it!

:D :p :)

This has been a long pondered thought of mine, so I thought I'd look into it a little more.

Actually, mandrel bent piping has the same exact I.D. from start to finish. So if you have a 2" cat-back exhaust, it is 2" all the way back, even at the bends. There is no degradation in inner diameter size whatsoever.

The best crush bends are made when the pipe is inserted with sand or what not while the bend is being made. That will keep the creases to a complete minimum.

The typical crush bends are made by just bending a pipe between two steel concave braces. these will tend to show creases at the bend.
 

·
P10 Geek
Joined
·
1,565 Posts
Damn Fast91SER. That was fast. Thanks for posting the pics. That helps explain it much better!!

CHECK THIS OUT:

http://www.bobsmuffler.com/mandreljob.htm

More pics of the above job and many others. And a great explanation of mandrel bend, etc. Awesome informaion on exhausts! Thanks Fast91SER!

That is similiar to what my custom 2.25" crush bent cat-back to Borla exhaust looks like. The bends are so minimal, you would almost say it was mandrel even though it isn't.

But those pictures are mandrel!!!!!!!

If I get the time, I'll post some pics of mine to show.
 

·
Registered
Joined
·
4,465 Posts
YEAH!! Now we're one big happy family again!!!!! :D
Im glad ya'll broke it down for me.
My bends didnt look too shabby on my SE-R.
 
1 - 20 of 22 Posts
Top