Well, we had a busy day yesterday installing all these upgrades. I had my father-in-law help me, my wife was busy taking the pics. Overall it wasn't bad. We were a solid 5 hours doing everything. We had only a couple of snags, but that was expected with a job this big. First thing I did was pull the fuses, (L99). We got car up and supported by car ramps at the front and jack stands at the rear, plus wood block for extra safety. I used a creeper for all the work under the car, but I would say the height was minimum for comfort. If you plan to do this in your drive/garage, (which is easily accomplished), I would try to get it at least 6" higher. I cut the pipes just before each muffler to get them out easier. I cut the pipes in a spot that would allow the factory system to be reassembled with butt band clamps if ever needed. Once cut, the mufflers pop right out. Be sure to spray all the rubber hangers with some WD40 or something. Both mufflers had water in them and the drain holes were plugged. Removed the cross bracket and undid the clamps at the cats and wiggled the rest of the system out, layed it on my chest and rolled it out the back. We had the system on the ground in 20 mins. Next came disconnecting the O2 sensors from the cats. This ended up being one the biggest PITA of the whole project! There is a secondary lock that has to be pulled out in order to release the lock of the connector body itself. The secondary lock needs to be squeezed to remove as it also has barbs on it. I tried to save them, and get them out the proper way, but no luck. I ended up snipping these little locks with some side cutters. No damage was done to the wires or main connector bodies or main locks. I removed the engine cover and intake system. Working one side at a time I removed the spark plug wires and the plugs too. We had air tools, I was able to get to all the exhaust manifold bolts with the air ratchet. With me up top and Doug on the ground, I unbolted the manifolds and he carried them out through the bottom. Lots of room. We had one O2 sensor harness hang up in the frame, so keep and eye for that. I took all the plugs and checked the gaps. All were bang on at 0.040". I applied anti-seize to the threads and flange area and put them aside. JBA 1812s set comes with new bolts. The factory bolts are a better quality. The JBA flange is the same thickness as the factory manifold so I reused the factory bolts. The factory bolts already had some thread locker on them. I applied some anti-seize to these bolts as well. I didn't get new manifold gaskets, but I did get new cat flange gaskets. I don't like reusing gaskets. The JBA's came with new gaskets for the head mount, that is why I didn't get new manifold gaskets. The gaskets that came with the headers were damaged in the box. I am not impressed with these at all! I think the gaskets they include are just junk! They were just loose in the box and I am surprised they weren't more damaged. I ended up having to reuse the factory gaskets. JBA raises the port flange around each exhaust port to get a better seal to the head. I would have liked to see this area a bit wider because when you use OEM gaskets the sealing surface coverage isn't across the whole width of the port on the header. We swapped the headers on the ground to the cats and slide them back up from the bottom. We started with the passenger side. The drivers side, JBA's will not fit from the bottom with the steering shaft inplace. We had to take it out, separate it and put the header in from the top, which does fit ok. Torqued all the factory bolts on the header to 18 ftlbs. The flange on the cats were tightened just till they were tight with air ratchet and wrench. You can see the flange close up as the gasket crushes down. The studs came out of the cats when removing the nuts. I also anti-seized them during reassembly. Put the plugs back in, and torqued them to 10 ftlbs or so. I applied some new dielectric grease to the plugs and coil connector and reconnected the wires. Push till you hear the "click". The MBRP system was pretty much straight forward. This the system specifically designed for the L99s. We just followed the instructions. That part went pretty smooth. After that we install the Roto Fab CAI. That has been discussed her many times before, but I will say it was easy and fun to put in. Once all together we fired it up, (sounded great) let all the oil and stuff burn off, we had a break, let it cool down and rechecked everything. Got the car down off the stands and went for road test. WOW, you can really hear all the cylinders roaring under load better, nice low rubble. I would say off the line it was about the same as before, but acceleration from 30km/h to 120+ is better! Nice tone at cruising speed, but once you floor it, wow, this sucker comes to life! MBRP did a great job masking the AFM. No drone, sound about the same as before, just a bit louder. No one should really have a problem with it. The exhaust sound in the cab is about the same level as the road noise. No problem with a conversation or listening to the radio!
Stock revs
After revs
Road test
Try to get the car about 6" higher than this for the best room.
We just cut this with Saws all.
I let it rest on my chest and rolled out!
Mufflers were full of water.
O2 sensor connector.
Air ratcheting the manifold bolts out.
Manifolds slide right down.
In this picture you can see the top O2 sensor harness is snagged on the frame. We were careful. No damage was done.
It took an extra 5 mins to get this side out because the one O2 harness got hung up. I knew the manifold was snagged on something but I couldn't see at the time. It pays to be patient and not get too rammy!
Here is the JBA header with the raised ports that press against the heads. I think these raised ports should be been wider to get more sealing surface with the OEM gaskets.
Here is the gasket JBA sends with the headers. You can see the damage this one suffered in transit. Ultimately I blame JBA because these were packaged just loosely in the box. The are a mult-layered type gasket, soft, felt like aluminum. Overall they felt cheap and junky. Maybe I am wrong. I think the OEMs are a great gasket! This is my review, so I can say what I want, LOL!
I just squeeze the drivers side header around the A/C line to get it in.
Here we go with the MBRP system. This is the new resonator section that replaced the stock one.
We just set up a few stands to support these sections while we bolted up the new MBRP cross bracket.
On the drivers side, the rear OEM spark plug wire can't be used because the new pipe is in the way. Here is a picture of how I think it was suppose to be routed. The JBA instructions kinda sucked. They didn't mention this at all. No pictures or anything! It is routed around from behind the header. Lots of clearance.
Thanks for reading!