Kuro Posted October 5, 2012 Share Posted October 5, 2012 Hi all, I'm looking for options to tuck my exhaust. I'm running Stance coilovers lowered just enough to get rid of excessive wheel gap, but even that takes my exhaust nearly to the street. Has anyone routed the exhaust so that it doesn't go under the rear axle? If so, please post some pics. I've seen one post where someone managed to mock up something that wouldn't take the standard route back there, but I can't seem to find it at all anymore. Oval tubing? Reroute? Side exit? Anything? I'm getting ready to do some more work on it in the engine bay, and a new exhaust will be swapped in, but I'd like to plan out something so that the exhaust isn't getting beaten up on the street. I'm not going to raise the car, so please don't suggest that. Thanks in advance! Here's the problem: Quote Link to comment Share on other sites More sharing options...
AkumaNoZeta Posted October 5, 2012 Share Posted October 5, 2012 The plan I had was to split the exhaust into two smaller pipes coming out the back (for my car I'm planning 3" splitting into 2 1.75") and having one going on either side of the diff like the twice pipes. Quote Link to comment Share on other sites More sharing options...
motomanmike Posted October 5, 2012 Share Posted October 5, 2012 Wow, that guy in your signature friended me on FB awhile back. I havn't even thought about buying anything from them but I won't now. I'm guessing you got burned pretty bad. As for the exhaust, i'm sure you can tuck it up above but it would have to be pretty precise and may require a flex pipe up towards the motor to minimize any possible movement. Good luck. I'm curious myself. That car is LOW man. Quote Link to comment Share on other sites More sharing options...
Kuro Posted October 5, 2012 Author Share Posted October 5, 2012 (edited) motomanmike, I have one shop look at it and they thought the only way is using ovals, I'm going to another shop (the guys that did my coilovers) so they can take a look, but I wanted to see what others may have already done. We can talk on the side about THAT guy in my siggy, I'm not angry anymore, but I can say that the flares on my car are custom (cause they only started out as BAMF flares but were reworked), even though he wants to believe they are BAMF. Grim, not a bad idea, but I have my tank in the way. I'm not swapping that out (not yet at least - but if I did, something would still be under the chassis not inside the trunk). Edited October 5, 2012 by Kuro Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted October 5, 2012 Share Posted October 5, 2012 What size is that exh.? 3" ? I think going oval is a good idea. TimZ used it, along with exiting in front of rear wheels. Do a search for his pics. I need to address my 4" exh. to. In this older pic, it was sitting higher Quote Link to comment Share on other sites More sharing options...
Kuro Posted October 5, 2012 Author Share Posted October 5, 2012 What size is that exh.? 3" ? I think going oval is a good idea. TimZ used it, along with exiting in front of rear wheels. Do a search for his pics. I need to address my 4" exh. to. In this older pic, it was sitting higher Nicely tucked, did it come down since that picture? Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted October 5, 2012 Share Posted October 5, 2012 Nicely tucked, did it come down since that picture? Car is 2" lower. What size is your exhaust? Quote Link to comment Share on other sites More sharing options...
Kuro Posted October 5, 2012 Author Share Posted October 5, 2012 Car is 2" lower. What size is your exhaust? 2.5", I will stay at that size for the new exhaust also. Quote Link to comment Share on other sites More sharing options...
Six_Shooter Posted October 5, 2012 Share Posted October 5, 2012 2.5" should have no problem being tucked up and have lots of ground clearance, even on a very lowered car. I have 3" on mine with a mild drop, and it's no lower than where the stock exhaust was for ground clearance, because I tucked it real tight against the diff. Before lowering: Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 5, 2012 Share Posted October 5, 2012 I'm running 3" exhaust and I just have it tucked as close to the differential as Six_Shooter stated above. In his second to last picture if you view the differential there, a little knuckle or tab or whatever you want to call it extends off the diff. Grind it off. It's not needed. Let's to tuck it up just a tad bit more and you don't have an annoying banging noise if your exhaust moves a little bit. Also if your exhaust rubs it too long there will be a hole there. Notice the marks from it in Six_Shooter's pictures. Another thing that allowed me to tuck my exhaust up really high was the fact that I've got an RT diff mount and I took the factory diff mount that holds the control arms up, and section the middle out and boxed in the ends that hold the control arm up, that way they are still strong and do their job, but the diff mount is out of the way. Some will say I've sacrificed chassis strength. In my opinion the RT mount is adding any support I may have removed from the chassis right above, most likely more than I removed seeing as how its made of thicker steel. As far as clearance this gave me, when it comes down to it it only gave me more clearance in the transmission tunnel because I've got the exhaust higher in there. Really though that is where it was needed because that is where speed bumps and other things are most likely to hit the exhaust. Seeing as how the wheels are right in line with the spot that you're having troubles with, it will be going up as the wheels do on speed bumps. Beyond that I would agree in saying either oval or square/flat tubing would be the only other way to get around that, short of cutting holes in the floor and running the exhaust inside the car and over that, which just sounds insane unless you're building a race car. Quote Link to comment Share on other sites More sharing options...
Six_Shooter Posted October 5, 2012 Share Posted October 5, 2012 Actually, I clearanced my exhaust by using a hammer and creating a divot in the tube. It did clear before that, but was close enough that on engine shut down, and sometimes start up it would tap against the diff. Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 6, 2012 Share Posted October 6, 2012 Actually, I clearanced my exhaust by using a hammer and creating a divot in the tube. It did clear before that, but was close enough that on engine shut down, and sometimes start up it would tap against the diff. I see, mine would do it if it was idling cold start. I don't have any cold start equipment. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 6, 2012 Share Posted October 6, 2012 The stock 432Z tucks twin 60mm pipes through those crossmember humps on a 240Z... The exhaust is NOT the lowpoint using the factory hangers back by the differential. The grinding of the differential is a good trick for larger singles, as is the idea to take two 280Z front diff crossmembers in order to run twin 2.5" pipes without hitting anything (or for that matter twin 3".... The key to not hitting is hanging it properly so it stays where it's supposed to stay, and having the pipes bent correctly so they don't stick down below frame. On my old 1970's era Greddy/Trust Goju System (twin 50mm pipes, mirroring the stock 432 setup) the stack of differential weights hung off the front diffy mount crossmember to null vibrations is all scarred up, but the pipes are up higher than that, unscathed. The stock hangers are used in the back. No knocking, bumping, or scraping. Pay attention when hanging it, hang it properly so it isn't moving, and you will be golden! Good Luck. Quote Link to comment Share on other sites More sharing options...
TimZ Posted October 6, 2012 Share Posted October 6, 2012 What size is that exh.? 3" ? I think going oval is a good idea. TimZ used it, along with exiting in front of rear wheels. Do a search for his pics. Here's what I did to avoid the problem completely. This was a 4" downpipe to twin 3" ovals on either side. You should should be able to fit a 2.5" oval easily in this manner. Quote Link to comment Share on other sites More sharing options...
johnc Posted October 6, 2012 Share Posted October 6, 2012 The only issue with an exit in front of the axle is trailer loading. The pipes are at the exact point where the car is lowest at the breakover point on the trailer. A beaver tail trailer helps as does 8' ramps. A 2.5" exhaust should fit up nice and tight and not cause any scraping issues. There are no "tricks" needed. Just find a competent shop that can install the exhaust properly. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 6, 2012 Share Posted October 6, 2012 Yeah.... Quote Link to comment Share on other sites More sharing options...
Kuro Posted October 8, 2012 Author Share Posted October 8, 2012 Ok here's another pic, I'll see what the other shop can do. I think the oval tubes might be a good way to go though. Quote Link to comment Share on other sites More sharing options...
Six_Shooter Posted October 9, 2012 Share Posted October 9, 2012 You should be able to get that tube up another inch and a half or so, and be almost level with the bottom of the diff. I'm not sure an oval pipe would make any difference in that area, due to limited width of space between the control arm retainer and the diff. Cutting off the little protrusion from the diff, as already suggested, could gain you a little width. Quote Link to comment Share on other sites More sharing options...
ModernS30 Posted October 9, 2012 Share Posted October 9, 2012 In my opinion there's almost two inches of room to move the exhaust up. You've just got a poorly made exhaust. It isn't hung very well. Quote Link to comment Share on other sites More sharing options...
Gavin Posted October 9, 2012 Share Posted October 9, 2012 Im super low and using 2.5". It is my low point and with a flex pipe and good mounts its served me well. For me leaving the rear compression damping high on the street has made a much bigger difference than height. A seemingly level manhole cover might lightly scrape my exhaust, but it very rarely will bottom out from compression on a flat surface. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.