Fiat 124 Exhaust Installation

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Fiat 124 Exhaust Installation

Postby Ryan @ GWR » Thu May 11, 2017 1:38 pm

2017+ Fiat 124 RoadsterSport Exhaust Installation Instructions
Good-Win Racing LLC Copyright 2016

These instructions cover the following RoadsterSport Fiat 124 items:
Muffler Delete, Midpipe & Cross-over pipe

Text only for now, will be updating with photos over time.

Difficulty on a scale of 1-5 (where 1 is beginner plug and play install and 5 is an engine swap)
Muffler: 1 (Just got your first set of tools? This is a good project to get your feet wet with)
Midpipe & Cross-over pipe: 3 (Requires working by “feel” & some specialty tools)

Tools Needed:
Soap & water in spray bottle
Socket set (10mm, 12mm, 13mm, 14mm, 15mm)
Bolt penetrant spray
⅞” Oxygen sensor wrench with flex head
Small flathead screwdriver
5 /8” open ended wrench
11/16” open ended wrench

Installation steps:
Full exhaust combo (Muffler delete, Midpipe, Cross-over pipe): Follow all steps 1-38
Muffler delete ONLY: Steps 1, 5, 6, 7, 27, 28, 35

The rear brake should be set and the car in gear and the car should then be safely raised and supported on a lift or with jack stands on a level solid surface (never work under a car held up by only a jack!!!).

1. Remove the plastic cover on the underside of the car just ahead of the rear right tire. There are 3 bolts and one plastic clip. 10mm socket for the bolts and a small flathead screwdriver for the clip.

RS Fiat Exhaust Install (11).jpg

2. Remove the X shaped brace from the bottom of the car. 4 bolts, use 12mm socket.

RS Fiat Exhaust Install (17).jpg

3. Remove the cross-brace from the bottom of the car. 4 bolts, use 12mm socket.

RS Fiat Exhaust Install (47).jpg

4. Remove the engine cover from the underside of the front subframe/engine. 9 bolts, use 12mm socket.

RS Fiat Exhaust Install (6).jpg

5. Spray rust penetrant on the four midpipe bolts: the two that join the muffler to midpipe and the two that join the midpipe to cross-over pipe. We recommend letting the penetrant sink in for at least 30 minutes.

RS Fiat Exhaust Install (39).jpg

6. Remove the two bolts shown above that join the muffler to the midpipe. Use 14mm socket.

7. Spray soapy water on the four rubber bushings that suspend the muffler from the hangers on the car. Then remove the rubber bushings from the muffler’s hanger rods. Leave the bushings attached to the car. We like to use a specialty tool for removal as shown in the photo, but with the soap and water to lubricate things you can remove these by hand.

RS Fiat Exhaust Install (26).jpg

RS Fiat Exhaust Install (38).jpg

It can help to have a second person hold the muffler up to prevent it from falling while you remove the last bushings. With all four bushings removed from the muffler, remove the muffler.

RS Fiat Exhaust Install (9).jpg

8. Spray soapy water on the single rubbing bushing that suspends the rear of the midpipe. Then remove the bushing from the midpipe. Leave the bushing attached to the car.

RS Fiat Exhaust Install (7).jpg

9. Remove the two nuts and springs that join the front of the midpipe to the cross-over pipe. Use a 14mm socket. Then remove the midpipe from the car.

RS Fiat Exhaust Install (28).jpg

10. Going back to the studs which you just removed the nuts and springs from, now remove the studs from the cross-over pipe’s flange. The studs have a short section with a hex for a wrench/socket. Use a 13mm socket.

RS Fiat Exhaust Install (32).jpg

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11. Spray rust penetrant on the base of the oxygen sensor as well as on the 2 studs that join the top of the cross-over pipe to the downpipe. These are all tucked up against the side of the engine below the turbo and it is a tight space.

RS Fiat Exhaust Install (37B).jpg

12. Loosen the nut for the bracket that holds the tail end of the cross-over pipe. Use a 13mm socket. Do not remove the nut yet.

RS Fiat Exhaust Install (3B).jpg

13. Now disconnect the oxygen sensor’s wiring from the car. The wiring is fixed in a few places. The first location is via a small bracket attached to the downpipe. Remove the nut here with a 10mm socket or wrench, whatever you can fit in that space.

RS Fiat Exhaust Install (37C).jpg

14. The next locations are hidden by the plastic wheel well liner in the front left wheel well. The majority of the liner can be left in place, only the lower rear portion needs to be released so you can pull the liner away to reveal the wiring. There are 3 plastic clips holding the liner to the car at the bottom/rear of the front left wheel well. Remove these by using a small flathead screwdriver to pop out the center portion of the clip, and once the center is out the outer portion can then be removed.

RS Fiat Exhaust Install (21B).jpg

15. Pry the lower back portion of the wheel well liner back to find the oxygen sensor wiring’s connector and 2 plastic clips holding the wiring in place. Disconnect the connector and remove the two plastic clips.

RS Fiat Exhaust Install (20B).jpg

16. The final location where the oxygen sensor wires are fixed is on a bracket attached to the left engine mount. The plastic clip itself is nearly impossible to reach, so skip that and instead remove the metal bracket from the engine mount. There is one bolt, use a 10mm socket.

RS Fiat Exhaust Install (35B).jpg

17. With the oxygen sensor’s wiring fully disconnected, now remove the oxygen sensor from the cross-over pipe. Use a ⅞” flex-head oxygen sensor wrench.

RS Fiat Exhaust Install (42).jpg

18. Remove the two nuts that join the top of the cross-over pipe to the downpipe with a 12mm socket. These are the two that you sprayed rust penetrant on in step 11. Because these are tucked high up next to the engine we’ve found it easiest to do with a very long socket extension or series of extensions so that the wrench handle is lower than the underside of the car.

RS Fiat Exhaust Install (15).jpg

19. Remove the bolt from the cross-over pipe bracket that you loosened previously in step 12.

20. Remove the cross-over pipe.

RS Fiat Exhaust Install (33).jpg

21. Installing the new cross-over pipe:

RS Fiat Exhaust Install (4).jpg

Fit the new cross-over pipe in place and loosely install the two nuts at the top and the bolt to the bracket. Then torque all three to 18-20 ft lbs.

RS Fiat Exhaust Install (44).jpg

22. Install the oxygen sensor in the cross-over pipe by feeding it through the front left wheel well. Fix the wiring in place in the same locations you removed it: one metal bracket to the downpipe (10mm socke), one metal bracket to the engine mount (10mm), and two plastic clips to metal brackets.

RS Fiat Exhaust Install (13).jpg

23. Connect the oxygen sensor’s wiring connector.

24. Install the supplied gasket on the outlet of the cross-over pipe. It's a snug fit. This usually takes a few taps with a mallet.

RS Fiat Exhaust Install (22).jpg

25. Thread the factory studs that were removed from the old cross-pipe into the flange on the new cross-over pipe’s outlet. Use a 13mm deep socket.

26. Install the front half of the midpipe on to the studs, then install the springs and nuts on to the studs and tighten the nuts down a bit to put tension on the springs. Leave this portion of the midpipe hanging for the moment.

RS Fiat Exhaust Install (43).jpg

RS Fiat Exhaust Install (34).jpg

27. Moving away from the midpipe, now install the rear "muffler delete":

RS Fiat Exhaust Install (29).jpg

Spray soapy water on the rubber hangers and install the larger portion of the muffler delete on to the passenger side hangers first.

RS Fiat Exhaust Install (2).jpg

28. Slip the included clamp on the smaller half of the muffler delete and then install that portion on to the driver’s side rubber hangers. With both halves now hanging, slide the clamp so that it is about half and half on each pipe. Lightly tighten the clamp with a 15mm socket.

RS Fiat Exhaust Install (19).jpg

29. Moving back to the midpipe. Slide the included slip joint clamp on to the front section of the midpipe with the flange pointed towards the passenger side of the car and the bolts oriented vertically.

RS Fiat Exhaust Install (41).jpg

30. Spray the blue polyurethane exhaust hanger with soap and water and then install the rear section of the midpipe by first attaching it to that poly hanger and then securing the rear flange to the front of the muffler delete. Use the supplied gasket and nuts/bolts at this junction. Use ⅝” and 11/16” wrenches/sockets to tighten. When tightening these bolts it can help to have someone hold the midpipe in place for you. Tighten to 25 ft-lbs.

RS Fiat Exhaust Install (50).jpg

RS Fiat Exhaust Install (36).jpg

31. Moving to the joint between the two midpipe halves, slide the clamp half way over each end, push the two pipes together as much as possible and tighten the clamp bolts with a 15mm socket to 30 ft lbs.

RS Fiat Exhaust Install (31).jpg

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32A. Tail pipe end alignment: tilting the tips

The slip joints in the system allow for lots of adjustment of the end tail pipe position. This is a good thing, but also makes it possible for you to get the alignment wrong if you don't take the time to adjust the alignment. First, check that the tips are pointed at the same angle by standing behind the car and comparing visually. If they are not, you can rotate the left side tip up or down within the slip joint clamp that you have not yet fully tightened. Once satisfied with the alignment, tighten the clamp bolts with a 15mm socket to 30 ft lbs.

32B: Tail pipe end alignment: midpipe effect on tip position

The midpipe length is adjustable within the slip joint between the two halves. Adjusted too short, the midpipe will pull on the rear muffler delete section resulting in the left tip being sucked in further than the right tip. If the midpipe is adjusted too long, it will likewise push on the rear muffler delete section causing the left tip to stick out further than the right tip. Stand behind the car to ensure that they appear even, and adjust the midpipe length within the slip joint if necessary.

33. Once you are satisfied with the tip alignment, ensure both slip joints are torqued down and then finally tighten the nuts on the springs/studs at the midpipe to cross-over pipe connection.

34. Reinstall the plastic cover ahead of the rear right tire with the 3 bolts and one plastic clip.

RS Fiat Exhaust Install (5).jpg

35. Check for leaks in the exhaust system by starting the car and while it is running feel with your hands around the joints. If you do not feel air escaping, everything is sealed well. Be careful, the exhaust will warm up quickly.

RS Fiat Exhaust Install (1).jpg

36. Once satisfied that there are no leaks, reinstall the X brace under the car. Check to ensure there is clearance between the brace and the midpipe. If necessary, you can adjust the clearance by loosening the slip joint clamp and pressing up on the midpipe while retightening it. If clearance is still an issue, you may need to shim the brace down by placing washers between the brace and the chassis.

RS Fiat Exhaust Install (49).jpg

37. Reinstall the cross brace under the car.

38. Reinstall the lower engine cover underneath the engine.

You're done. Enjoy!

RS Fiat Exhaust Install (8).jpg
RS Fiat Exhaust Install (29).jpg
Ryan @ GWR
Posts: 320
Joined: Fri Oct 17, 2014 11:37 pm

Re: Fiat 124 Exhaust Installation

Postby Brian » Fri Jun 16, 2017 9:59 am

Great job by Ryan!

My additional trouble shooting tips. WE have given a ton of adjustment, too much adjustment for those who do not take the time to play with the slip joints. Two slip joints in the system, plan some fiddle time with each to get it all right. The midpipe slip joint is the most important, and part of the KEY to getting tip alignment right at the back. Why? Start with understanding that the exhaust system is not actually running down the middle of this car, because the driveline runs down the middle. The exhaust system is run down the passenger side of the car, some inches off the center. Now let's add the fact that the midpipe is adjustable for length at the slip joint. Add this all up and it means setting midpipe length can rotate the rear muffler delete one direction or the other. If midpipe is adjusted too short, it pulls in the passenger side tip. If midpipe is adjusted too long, it tends to push out the passenger's side tip and rotate driver's side tip too far inward.

Getting midpipe length 'just right' can be a challenge on jack stands and many will need to get the car on a lift so they can play with length to get it right. Customers who just hang it on the car and bolt it down might get lucky and get it right by accident, but most folks are going to need to look at it and think about what they need to do with the length to get the rear muffler delete section lined up correctly. One tip here is lube up the midpipe joint with soap/water so you can slide it back and forth easily and get it adjusted to hang neatly in alignment with the rear muffler setup. Pay attention to clocking position of rear section of midpipe, if flange angle does not line up neatly with muffler flange angle, that's usually a goof on clocking position of midpipe rear section. Turn that rear midpipe section clockwise or counterclockwise and slide it in and out of front section until you can pinch the flange of midpipe to flange of muffler with just two fingers and they neatly align. Resist the urge to jack the flanges into position if alignment is not good when you pinch the flanges together with your fingers, because jacking flanges despite bad angle alignment can rotate the rear muffler setup one direction or the other and make final tip alignment difficult.

Once midpipe length is right, muffler delete slip joint is used to fine tune driver's side tip position to match height of passenger side tip. Once again here it is important to understand that slip joints are your friend in the adjustment process, if you shove that slip joint 100 percent closed it will make driver's side too short and that will pull driver's side tips under the car. You need gap for slip joint to work! Again, lube up that joint a little with soap/water and make nuts/bolts finger tight and you can have some fun adjusting gap inside the clamp and clocking position of rear driver's side tip section so you can match position of passenger side tips. Note that even the order in which you torque the two bolts at the flange to midpipe will make some change in how that passenger side tip hangs. So, get the passenger tip even in the hole, then work on driver's side using the slip joint in muffler delete, adjust how it sits in the rubber hangers as needed, then alternate use of wrench on the two bolts for flange to midpipe a few turns at a time on each bolt to get even sandwich of the gasket. You may not be happy with how it hangs on the first attempt, it might take two or three rounds of having it loose and adjusting how it hangs on the rubber hangers and then slip joint position before it all finishes up the way you want it.

Brian Goodwin
Good-Win Racing
Site Admin
Posts: 8799
Joined: Tue Feb 15, 2005 11:44 am
Location: San Diego CA

Re: Fiat 124 Exhaust Installation

Postby Ryan @ GWR » Thu Jun 29, 2017 12:59 pm

Photos have been added!
Ryan @ GWR
Posts: 320
Joined: Fri Oct 17, 2014 11:37 pm

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