Performance Robbing V-10
#41
06-28-2011, 09:10 PM
Wanted to update the results and also answer Jimy' question:
On my truck I don't have after CAT O2 sensors. I have a single 2 1/4" exhaust down pipes that run all the way down past the Transfer Case. The OEM CAT's are 2 1/4" in and out! Anyway the CAT's are side by side and enter the OEM muffler as a dual in 2 1/4" and a single center 3" out going to the tail pipe.
The muffler (Magnaflow) I bought was a 2 1/2 dual in and a 3 1/2" single center out. This was the wrong muffler! Magnaflow does not make the correct direct replacement muffler for this set up, however I made it work........LMFAO
What I did was cut between the CAT and the muffler right on the clamp/hanger. I cut each outside off the hanger so just the inside bolt hole on the hanger remained. I then got a 2 1/4" ID X 2 1/2 OD coupler and smashed it into the muffler end to make it work then cut 1/2 of each end off to make a perfect fit. It took a Big Fu$king Hammer (BFH) and a sawzall, added a 2 1/4" clamp and a 2 1/2" clamp on each side to make it work. On the back side, the tail pipe was actually 3" and the was muffler 3 1/2", this I found out was a great combination because I'll have a 4" tail section made.
The internal is a straight through design (which is the best...IMHO) and combines together into a 3 1/2" outlet, but internally the Y pipe is made! They did the best job by offsetting the top to bottom weld to create a cyclone type junction!Anyway, I simply had a muffler shop weld me up a coupler from muffler side 3 1/2" ID to a 3" OD to slip over the old system with a total length of about 8". Now just a heads up, 3 1/2" exhaust is a b!tch to find! Nobody bends it/has it and nobody cares! You are better going to a 4" exhaust and I will have one made later!
I gutted the CAT's and hooked it all up, all I can say is I'm happy with throttle response and power, with no CEL's.....LOL.....They weren't very dirty or plugged but you could see about 1/3 blockage. I still have the air pump hooked up so I need to disconnect it or gut it. You can defiantly feel a difference, but not enough! I think maybe next year I might pull the motor out, bore it .030 over, install a larger cam, smooth the heads, possible flat top pistons, and put her back together.
The truck does stink like an older truck enough to make me think it's gotta running rich (besides the bad fuel mileage), so I ordered a new set of Desno O2 sensors (Factory) and I am awaiting the results. Anyway it was like 86 F outside when I measured the resistance on the air charge sensor against the coolant temp sensor as they are the same values 8,150 and 8,195 and as you can see I got basically the same reading at 10,000 ohm's.
I'll update after the O2 sensors are installed.
BTW<------ www.rockauto.com had the best deal on Desno O2 sensors I could find.
*UPDATE*
Got the 2 Desno sensors from www.rockauto.com for $61.50 shipped and installed. Truck is running a hell of a lot better. Still have some issues with that dead spot but I'm still working on it. Just towed my 5000 lbs boat 150 miles and got 10 mpg's so that's a little better......LOL
On my truck I don't have after CAT O2 sensors. I have a single 2 1/4" exhaust down pipes that run all the way down past the Transfer Case. The OEM CAT's are 2 1/4" in and out! Anyway the CAT's are side by side and enter the OEM muffler as a dual in 2 1/4" and a single center 3" out going to the tail pipe.
The muffler (Magnaflow) I bought was a 2 1/2 dual in and a 3 1/2" single center out. This was the wrong muffler! Magnaflow does not make the correct direct replacement muffler for this set up, however I made it work........LMFAO
What I did was cut between the CAT and the muffler right on the clamp/hanger. I cut each outside off the hanger so just the inside bolt hole on the hanger remained. I then got a 2 1/4" ID X 2 1/2 OD coupler and smashed it into the muffler end to make it work then cut 1/2 of each end off to make a perfect fit. It took a Big Fu$king Hammer (BFH) and a sawzall, added a 2 1/4" clamp and a 2 1/2" clamp on each side to make it work. On the back side, the tail pipe was actually 3" and the was muffler 3 1/2", this I found out was a great combination because I'll have a 4" tail section made.
The internal is a straight through design (which is the best...IMHO) and combines together into a 3 1/2" outlet, but internally the Y pipe is made! They did the best job by offsetting the top to bottom weld to create a cyclone type junction!Anyway, I simply had a muffler shop weld me up a coupler from muffler side 3 1/2" ID to a 3" OD to slip over the old system with a total length of about 8". Now just a heads up, 3 1/2" exhaust is a b!tch to find! Nobody bends it/has it and nobody cares! You are better going to a 4" exhaust and I will have one made later!
I gutted the CAT's and hooked it all up, all I can say is I'm happy with throttle response and power, with no CEL's.....LOL.....They weren't very dirty or plugged but you could see about 1/3 blockage. I still have the air pump hooked up so I need to disconnect it or gut it. You can defiantly feel a difference, but not enough! I think maybe next year I might pull the motor out, bore it .030 over, install a larger cam, smooth the heads, possible flat top pistons, and put her back together.
The truck does stink like an older truck enough to make me think it's gotta running rich (besides the bad fuel mileage), so I ordered a new set of Desno O2 sensors (Factory) and I am awaiting the results. Anyway it was like 86 F outside when I measured the resistance on the air charge sensor against the coolant temp sensor as they are the same values 8,150 and 8,195 and as you can see I got basically the same reading at 10,000 ohm's.
I'll update after the O2 sensors are installed.
BTW<------ www.rockauto.com had the best deal on Desno O2 sensors I could find.
*UPDATE*
Got the 2 Desno sensors from www.rockauto.com for $61.50 shipped and installed. Truck is running a hell of a lot better. Still have some issues with that dead spot but I'm still working on it. Just towed my 5000 lbs boat 150 miles and got 10 mpg's so that's a little better......LOL
Last edited by hydrashocker; 07-05-2011 at 01:04 PM.