Anybody tried to fit a straight cat test pipe without the 1.5" drop?
Anybody tried to fit a straight cat test pipe without the 1.5" drop?
Some of you might remember my post last summer about the melted bag of peanut M&Ms on the floor of the passenger side, and my wife's toasty feet. Also, my MPGs have really tanked over the past several months. Been thinking about installing a cat test pipe to see if a plugged cat is the problem.
However, I can't find a local shop with a 4" die to bend the 1 1/2" kink , although they can swage (pooch) the end to fit the down tube. Will a straight-shot work? I notice the commercially available ones have the kink.
Would like to avoid dropping $100 + shipping on a nice stainless commercial test pipe, since I can make one (aluminized) without the kink for under $30. Especially where it's a temporary install, as I have emissions to worry about in a few months
However, I can't find a local shop with a 4" die to bend the 1 1/2" kink , although they can swage (pooch) the end to fit the down tube. Will a straight-shot work? I notice the commercially available ones have the kink.
Would like to avoid dropping $100 + shipping on a nice stainless commercial test pipe, since I can make one (aluminized) without the kink for under $30. Especially where it's a temporary install, as I have emissions to worry about in a few months
Some of you might remember my post last summer about the melted bag of peanut M&Ms on the floor of the passenger side, and my wife's toasty feet. Also, my MPGs have really tanked over the past several months. Been thinking about installing a cat test pipe to see if a plugged cat is the problem.
However, I can't find a local shop with a 4" die to bend the 1 1/2" kink , although they can swage (pooch) the end to fit the down tube. Will a straight-shot work? I notice the commercially available ones have the kink.
Would like to avoid dropping $100 + shipping on a nice stainless commercial test pipe, since I can make one (aluminized) without the kink for under $30. Especially where it's a temporary install, as I have emissions to worry about in a few months
However, I can't find a local shop with a 4" die to bend the 1 1/2" kink , although they can swage (pooch) the end to fit the down tube. Will a straight-shot work? I notice the commercially available ones have the kink.
Would like to avoid dropping $100 + shipping on a nice stainless commercial test pipe, since I can make one (aluminized) without the kink for under $30. Especially where it's a temporary install, as I have emissions to worry about in a few months

Short Term solution (very)
Do you wish to test to see if the cat is the problem, then maybe just remove the cat and do not put anything in place of it? You may rile a few neighbors but it should give you and answer quickly about the cat.
I did this procedure with a '89 Ford F-250 which had a 5.8L gasser and determined very quickly the cat was the problem. I ordered a replacement and rode my bicycle or used my wife's vehicle for 5 days until I received the new one.
L8r,..........dogger
I did this procedure with a '89 Ford F-250 which had a 5.8L gasser and determined very quickly the cat was the problem. I ordered a replacement and rode my bicycle or used my wife's vehicle for 5 days until I received the new one.
L8r,..........dogger
Update, I just ended up prying my wallet open and paying the $100 for the MBRP test pipe. I guess I can sell it later.
I immediately noticed better throttle response (especially on the low end) & smoother idle. That tells me something was up with the cat, but haven't run enough miles yet to check the mpgs.
Downsides are the exhaust is nauseatingly stinky and now I smoke people out when it kicks down. Some of you are chuckling and thinking "what downside?", but I like to think of myself a responsible diesel truck owner.
But at least it's not any louder.
That said, I do have emissions to worry about- can anyone recommend a aftermarket high-flow cat? Cheap?
I immediately noticed better throttle response (especially on the low end) & smoother idle. That tells me something was up with the cat, but haven't run enough miles yet to check the mpgs.
Downsides are the exhaust is nauseatingly stinky and now I smoke people out when it kicks down. Some of you are chuckling and thinking "what downside?", but I like to think of myself a responsible diesel truck owner.
But at least it's not any louder.That said, I do have emissions to worry about- can anyone recommend a aftermarket high-flow cat? Cheap?
Why not just gut out the old cat so it appears to be intact? I doubt they will know the difference. I know we just passed the law that we don't need to deq anything over 6k lbs., might want to check on that. Best of luck.
Trending Topics
I bought a test pipe with the help of the above post Larry Ellis (Top). I have past my yearly safety check with no problems. My truck doesn't smell any different than what a diesel should smell like. The only time I get any black smoke is when I put my truck in Tow/ Haul mode and purposely gun it above 2,000 rpm's to get a tail-gater off my tail! In fact with my Cat removed it's a lot quieter that when I had my split open Cat still on my truck (which made my inside cab pretty hot in the summer and it was really loud as well). My rear pipe hangs down much lower than before but at least it doesn't blacken my back bumper any more.
Thanks guys, appreciate the advice.
I may gut it but with the offset I think it would be difficult (but prudent) to insert a liner through the cat to keep the flow from being disturbed by the gutted chamber. Got nothing to lose by trying though...
My kids asked me the other day why the corner of my rear bumper was suddenly always black
.
I may gut it but with the offset I think it would be difficult (but prudent) to insert a liner through the cat to keep the flow from being disturbed by the gutted chamber. Got nothing to lose by trying though...
My kids asked me the other day why the corner of my rear bumper was suddenly always black
.
Sorry I'm late
.
On the 03 I had, I welded in a straight 4" "test" pipe. "Swaged" the down pipe end with a 12# mini sledge. Best $40 I spent on that truck.
Used to be able to get a 47 state 4" Magna Flo cat for $250
.On the 03 I had, I welded in a straight 4" "test" pipe. "Swaged" the down pipe end with a 12# mini sledge. Best $40 I spent on that truck.
Used to be able to get a 47 state 4" Magna Flo cat for $250
Thread
Thread Starter
Forum
Replies
Last Post
JaimeG
3rd Gen High Performance and Accessories (5.9L Only)
2
Mar 26, 2009 06:58 AM
PEAKSTRYDE
Suggestions, Comments and Site Questions
1
Oct 11, 2007 04:20 PM
Jordan5687
Performance and Accessories 2nd gen only
2
Feb 14, 2007 05:00 PM
natlchamp2k4
Performance and Accessories 2nd gen only
10
Dec 6, 2005 09:38 PM




