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Out of shear cussedness I bought it from Parts.com for the same price, which doesn't say if they actually have it but it'll be up to 5 days AFTER they ship it out. So I'm expecting mid May and hope to be pleasantly surprised.
I've had good luck with Parts.com (so far), everything I've ordered has been in-stock and arrived on time.
Found this in the classified. Looking at the other posts and it's current condition, it looks like they did nothing to fix the car while they owned it. Still has a faulty drivers front o2...
OK, so here we go. Old stuff is OUT. Took several heat cycles as parts came off to get the hardware hot enough to come loose. Only broke the two mid pipe clamp bolts. Mid pipe didn't want to come off the cat pipes and a couple wires behind the gas tank got yanked by the hanger while shaking everything vigorously. Took a short nap under the car once it was out in celebration.
Getting the cat pipes off sucked. Lots of lube, several 2 minute heat cycles and plenty of stink once finished. Used about 16" worth of extensions and a 14 mm 6 point deep well socket along with a short length of pipe on the ratchet. The torque on the extension resulted in violence each time the nut moved. The hangers bolted to the bell housing and held the cat pipes up while the manifold nuts were removed. Then I cut the straps with a whiz wheel. Once the cats were out of the way, the brackets came off with a 13 mm socket and wrench. I did need to remove the ground clamp on one side as Jaguar did the o2 sensor mounts bass ackwards. The sensor connectors plug into a bracket that is bolted to the tranny and the chassis wiring plugs into it, opposite of logic.
Notice how small the replacement cat is in comparison to the OEM one. Kind of kicking myself for not buying at least one more J bend and length of straight pipe. I didn't appreciate how much more pipe I'd need.
Finally since we are on another page, the shot of the new bits. Bottom shows the idea behind the exhaust pipe. Resonator being used as a muffler and a straight pipe that needs a butterfly valve installed.
I'm going top work front to back, get the o2's out, cut the flanges off the old cats and see what fitment I can get. Front resonator is going away in exchange for an X pipe. Back in the day Dr. Gas used to have dimension for DIY X pipes but he pulled them from his site. If memory serves, 30-40% of pipe area should be put into the X opening or 3.8 square inches for a 2.25" pipe. I usually eyeball the oval and compare it to the round pipe. Pretty small crossover for this little stuff.
I will say that once the mid pipe was gone, the engine sounded right nasty with gutted cats. More to come once I wash off the crud. This is when it gets fun.
OK, done for the night. Had to take the o2 sensor plugs apart to get a closed end wrench on so they would come out and not strip. Drivers side up stream o2 is a no name replacement. Cut the dead stuff off the pipes in prep for fitment.
OK, done for the night. Had to take the o2 sensor plugs apart to get a closed end wrench on so they would come out and not strip. Drivers side up stream o2 is a no name replacement. Cut the dead stuff off the pipes in prep for fitment.
So there's 2 sensors on each cat? (One green wire, and one blue, in the earlier picture.) Thought maybe I was seeing something else.
I love threads like this. Can't wait for the final result.
My back can't either. Had to get an old man pad for the cold concrete yesterday. I'll be in and out from under the car 50 times today.
Originally Posted by ajzride
Any chance we get a video clip of it running with no exhaust, just for giggles?
I have a GoPro and thought about it but most YouTube videos of exhaust aren't good representatives of what it really sounds like. Just the mid pipe sounded like a 70's buick with a blown muffler, Glug, Glug, Glug at idle with a faster tempo the harder the go pedal was pushed. No mids and it reminded me of a quieter Nascar engine with a nice rasp when you'd whacked the throttle. It only took a minute to heat up the engine is really low on coolant until I get the replacement hose installed.
Originally Posted by kj07xk
So there's 2 sensors on each cat? (One green wire, and one blue, in the earlier picture.) Thought maybe I was seeing something else.
Yeah, I thought the upstream one went into the head pipe, not the cat so I only bought 2 bungs. I'll need to salvage two from the dead cats. The downstream one is in the middle of the cat. The cats have a pre bed and main bed and the OBDii mid bed sensor (blue) looks for some change from the upstream one (green) to satisfy that the emissions are working. I guess they don't care or can't read the final result from the main bed. The upstream one has a couple holes (a lot less than prior generations) and the down stream one looks normal with a bunch of holes. The passenger side green one rattles so I suspect it's fubar inside. I'm still getting codes for the drivers so possibly I have a chassis wiring problem (or the no name sensor crapped out).
About ten times under the car so far. The flange stubs from the old cat pipes were too short so I found this length of old exhaust behind the shed. Cut the two lengths out of it.
That allowed me to drop the cats low enough that I won't need to fight the pipe up too them. Pics are with the camera laying on the floor.
Finally welded together. lots of tacking, then fitting, mark the new fit and final weld. red circles mark the upstream o2 locations. That next once the pipe cools off. Welding .030 stainless wire with straight argon isn't working out well on the small 110 welder. Might have to fire up the big one.
Last update for the day, I'm whopped. As said before, I needed to mount o2 bungs in the pipes. Since it's only 2.25" pipe and it needs all the flow it can get to support 420 hp I chose to mount the o2's in the transition part of the cats. The bungs I got from Summit didn't have a shoulder so they wouldn't fall into the hole so I turned them on the lathe, the drilled / die ground the holes in the cats to fit.
Once welded I still needed to go back through them with a 18 x 1.5mm tap to chase the holes. Picked that up a NAPA a couple years ago when we went EFI 350 in my dad's cabin cruiser.
No other pics until it was done. The little welder finally got tossed aside and the Miller 210 took over with regular wire. Overall I did struggle more than I'd like but the fit up turned out well.
I still need to remove the broken bolts from the clamps but that'll wait for another day.
You might wonder why I chose to fit the cat pipes up to the front of the mid pipe? I needed the clamp sections parallel to help get them apart. They are pretty close and dropped once the manifold nuts were loosened. I'm also going to use the form of the existing front end as a template for the X pipe. That should be tomorrow's project. I was going to make the muffler assy. but I think I'm going to keep moving from front to rear.
I did take a short break and ran out to Autozone to order two new Denso upstream o2's. Those and a can of red caliper paint set me back $250 but I hope that will take care of the last two engine codes.
OK, spent a couple hours this morning getting stuff cleaned up, the welding bench cleaned up and laying out the exhaust tunnel of the car. CL is tunnel and exhaust center line. The outside hockey stick is the outer wall. The 45` line is the ideal X pipe start angle. It'll allow me to have a 90` bend with the cross over port.
Used some aluminum blocks to lay out the center line for where the cut the J bends. There is some stress and distortion in the pipe from the forming process but these still flow gobs more than crinkly bent exhaust shop stuff.
Should end up like this. I'll fab the X and then graft it into the OEM mid pipe. 15 7/8" is the center line width of the clamps. I may weld some straps at the clamp end before cutting or I may do the fitment on the car. I'd much rather do it on the bench but it needs to fit the car. Ugh...
That's interesting, looks like 2.5" pipe which I'd expect on a 5.0 liter engine. I did notice the other night that in my drawing on the table top that I did not allow room to uncouple the exhaust. Going to need to cut and move the bends back towards the clamp flanges on the mid pipes. I'll be back on it later this week. Twelve hour work days cuts into fun time.
That's interesting, looks like 2.5" pipe which I'd expect on a 5.0 liter engine. I did notice the other night that in my drawing on the table top that I did not allow room to uncouple the exhaust. Going to need to cut and move the bends back towards the clamp flanges on the mid pipes. I'll be back on it later this week. Twelve hour work days cuts into fun time.
Looking at your fab. work I wonder why you didn't consider an H pipe instead of fab'ing up the X pipe. It looks like the H would fit in right where the 2 pipes went into the resonator.
Looking at your fab. work I wonder why you didn't consider an H pipe instead of fab'ing up the X pipe. It looks like the H would fit in right where the 2 pipes went into the resonator.
The difference is in how they work. The Grumpies site has more info but basically with the small port between each bank on an X pipe each exhaust pulse gets split into both pipes. This allows an undersized / HP 2.25" exhaust to flow much more. Most commercial X pipes are just a cross and they don't manipulate the pulse so it goes down both paths. That's the 'secret' of Dr Gas's X pipe. My exhaust is effectively only four feet long from the manifold to the X.
An H pipe just balances the pulses from side to side without allowing more flow from bank to bank. The pulses are just too quick and the time delay means they run into a pulse from the other bank that's coming towards them. The audible characteristics also favor the X. The X pipe pulls hardest at @ 3200-3600 rpm and sounds strongest at the same time. An H pipe pulls at 2500 rpm and tended to drone. I hate drone and hope to have a quiet at cruise raspy racing sounding exhaust note. I'm not sure how the little resonators are going to effect the sound at cruise though (feel they are too short).
The difference is in how they work. The Grumpies site has more info but basically with the small port between each bank on an X pipe each exhaust pulse gets split into both pipes. This allows an undersized / HP 2.25" exhaust to flow much more. Most commercial X pipes are just a cross and they don't manipulate the pulse so it goes down both paths. That's the 'secret' of Dr Gas's X pipe. My exhaust is effectively only four feet long from the manifold to the X.
An H pipe just balances the pulses from side to side without allowing more flow from bank to bank. The pulses are just too quick and the time delay means they run into a pulse from the other bank that's coming towards them. The audible characteristics also favor the X. The X pipe pulls hardest at @ 3200-3600 rpm and sounds strongest at the same time. An H pipe pulls at 2500 rpm and tended to drone. I hate drone and hope to have a quiet at cruise raspy racing sounding exhaust note. I'm not sure how the little resonators are going to effect the sound at cruise though (feel they are too short).
I was led to believe the HP benefit of the X pipe were in the higher rpm band where it would pull out the exhaust . Somewhere in the 5K rpm range . The H pipe on the other hand was a benefit in the lower rpm range and improve evening out the balance/flow. The noise on my 5.0L at 4K rpm is outrageous as the butterfly valves open around then. We'll wait for your system to sound out. Enjoy.
I was led to believe the HP benefit of the X pipe were in the higher rpm band where it would pull out the exhaust . Somewhere in the 5K rpm range . The H pipe on the other hand was a benefit in the lower rpm range and improve evening out the balance/flow. The noise on my 5.0L at 4K rpm is outrageous as the butterfly valves open around then. We'll wait for your system to sound out. Enjoy.
It does, but more so because the X allows both downstream pipes to carry the exhaust. By it's construction and firing order a V8 loads the banks unevenly. So as a series of pulses hit the restriction load in one bank the X allows some of the overpressure to flow into the (relatively) low pressure bank. Another virtue with the pulses is as the pass the port they'll pull a negative pressure pulse onto the other bank similar to the venturi effect but different. Supposedly you can tune the pipes so they'll boost at whatever RPM you need them. That's way beyond my experience though. The 'Two stroke handbook' is a really good reference about how exhaust pulses work.
In other news, last night I installed the new front o2's and today the coolant hose showed up while I was taking a nap after installing a couple little gears at work today:
So, hose or exhaust? Stood the hood up so far and realized I need to remove the top cross member to access the coolant pump.
03-31-2017, 10:50 AM
PROGRESS
