Cheaper Headers Alternative - 4.0L & 4.2L S/C ???
#22
Under the first ruling, some aftermarket manufacturers developed "shorty headers" to keep the cats in the same OEM location (close to exhaust ports as possible). These shorty headers are now illegal in California. Shorty headers produced reduced gains compared to long-tube headers, say in the area of 10 hp. The shorties resemble the tuned OEM manifolds shown above.
I know that several tuners have tried to reason with CARB arguing that the efficiencies of long-tube headers cause lower overall emissions long-term than shorties. In my personal experience CARB is very rigid, non-technical and theological in its rulings.
I know that several tuners have tried to reason with CARB arguing that the efficiencies of long-tube headers cause lower overall emissions long-term than shorties. In my personal experience CARB is very rigid, non-technical and theological in its rulings.
I have been looking/researching for Jaguar headers. Came across one mfg in UK (forget the name) advertising in Jaguar World, but could not access their web site. They were asking silly money for headers, which looked like simple shorties.
In the '05 era (not that long ago) many headers were still steel with coatings like JetHot. These coatings are very durable, but the market has changed a bit and customers are demanding stainless steel headers. SS is much harder to work, and some vendors have farmed out their header mfg to SS specialists, like American Racing Headers (AFR).
American Racing Headers is well-established and has a good reputation for quality/performance. Some months ago I emailed AFR asking if they were interested in producing headers for Jaguar post '07 XK/XKR. They replied asking production numbers. I guessed at well over 75,000 world wide. To date no further comment/interest from AFR.
I wondered if anyone produced headers for the American Ford Thunderbird '02-'04, which used the Jaguar-designed motor. I found one source: 02-04 Ford Thunderbird Headers from Stainless Works at Andy's Auto Sport. I am uncertain whether or not Jaguar and Ford used the same basic cylinder heads. One would logically compare exhaust manifold gaskets to confirm this. Not long ago Stainless Works was showing the T-Bird header on its site, but now they seem involved only with custom applications. Stainless Headers Mfg., Inc. fabricates custom headers in stainless and mild steel. I suspect the market for T-Bird headers was miniscule.
I have not contacted Stainless Works to date. They are located in Fargo, North Dakota, far from any major city. At this time I am personally a bit cool on the subject, realizing that improvements to a cat forward exhaust would be a major pioneer project for me. I'm still in a research mode.
In the '05 era (not that long ago) many headers were still steel with coatings like JetHot. These coatings are very durable, but the market has changed a bit and customers are demanding stainless steel headers. SS is much harder to work, and some vendors have farmed out their header mfg to SS specialists, like American Racing Headers (AFR).
American Racing Headers is well-established and has a good reputation for quality/performance. Some months ago I emailed AFR asking if they were interested in producing headers for Jaguar post '07 XK/XKR. They replied asking production numbers. I guessed at well over 75,000 world wide. To date no further comment/interest from AFR.
I wondered if anyone produced headers for the American Ford Thunderbird '02-'04, which used the Jaguar-designed motor. I found one source: 02-04 Ford Thunderbird Headers from Stainless Works at Andy's Auto Sport. I am uncertain whether or not Jaguar and Ford used the same basic cylinder heads. One would logically compare exhaust manifold gaskets to confirm this. Not long ago Stainless Works was showing the T-Bird header on its site, but now they seem involved only with custom applications. Stainless Headers Mfg., Inc. fabricates custom headers in stainless and mild steel. I suspect the market for T-Bird headers was miniscule.
I have not contacted Stainless Works to date. They are located in Fargo, North Dakota, far from any major city. At this time I am personally a bit cool on the subject, realizing that improvements to a cat forward exhaust would be a major pioneer project for me. I'm still in a research mode.
The following users liked this post:
Panthro (05-29-2016)
#23
Thanks, that correlates with the 4 to 1 headers made by Buckhead Imports which didn't show any gains (well only marginally on a heavily tuned car about 10/15 rwhp).
#24
So I haven't given up on this one...
The biggest issue from what I can tell is space, there just isn't much room to get the manifolds in there. Good example in this pic.
You can see how the stock manifolds sit right below the heads. If they "have" to be like that, then there isn't much hope...
BUT
Just for interests sake, these are the "design" of header that we would have to look at, kind of funny that a Chev GenIV LS2 would need the exact same branching as our AJ-V8's
Left side
Right side
Check out the branching, exactly the same as what we need.
These ones are made by Pacemaker (an Aussie company, not sure if made local or in China) for the Holden Commodore running a 6.0L N/A V8. They are short like that to keeps the cats in the factory position.
Sizes of the "Short Tri-y" in the pics above are are 1-3/4" primaries, 2" secondaries, 2-1/2" collector with flange. My gut feeling selection would be a 3" collector for the AJ-V8's looking for >600HP.
Pacemaker do make a "Long Tri-y" with the same primary & secondary sizes, but a 3" collector.
The long version with 3" collector. Also 1-3/4" primaries, 2" secondaries.
So obviously these don't fit our cars. But it's the right concept. If one could imagine the short version with a 3" collector, twist it & bend the shape to fit, would be the kind of design we will need.
Any comments on the sizing? I guess the first thing will be to get hold of a stock exhaust manifold gasket & check the port sizes. But my memory did serve me well, the "standard" size for 4-1 headers on the big capacity V8's in Oz is 1-7/8" primaries, to a 3" collector.
Looking for off the shelf bits to try & cobble something together, I came across Burns Stainless. They have pre-sized merge collectors, which were sized using thier Burns Stainless LLC - X-Design Exhaust Header Design Program the sizes don't quite match up when trying to put together a 4-2-1 header
Primary-Secondary......Secondary-Collector
1-1/2" to 2-1/8".........2-1/8" to 3"
1-5/8" to 2-1/4".........2-1/4" to 3-1/4"
1-7/8" to 2-5/8".........2-5/8" to 3-3/4"
Much bigger than the ones Down Under (I don't think that's ever been said before )
Another interesting link here How To Calculate Muffler Size and Exhaust Pipe Diameter | Exhaust Videos
We run twin systems, so how does it look for pipe size;
I'm going to assume flywheel HP is shown in the table e.g. my XJR runs a twin 2-1/4" system, and was making 400HP from the factory. Looks about right.
1-5/8" primaries should be good for 700HP, 1-3/4" might be a bit of an overkill. The Burns combo of 1-5/8" to 2-1/4" to 3-1/4" looks good. Just a matter of getting it to fit...
Will take time, but at least it's clean what direction to go in now.
The biggest issue from what I can tell is space, there just isn't much room to get the manifolds in there. Good example in this pic.
You can see how the stock manifolds sit right below the heads. If they "have" to be like that, then there isn't much hope...
BUT
Just for interests sake, these are the "design" of header that we would have to look at, kind of funny that a Chev GenIV LS2 would need the exact same branching as our AJ-V8's
Left side
Right side
Check out the branching, exactly the same as what we need.
These ones are made by Pacemaker (an Aussie company, not sure if made local or in China) for the Holden Commodore running a 6.0L N/A V8. They are short like that to keeps the cats in the factory position.
Sizes of the "Short Tri-y" in the pics above are are 1-3/4" primaries, 2" secondaries, 2-1/2" collector with flange. My gut feeling selection would be a 3" collector for the AJ-V8's looking for >600HP.
Pacemaker do make a "Long Tri-y" with the same primary & secondary sizes, but a 3" collector.
The long version with 3" collector. Also 1-3/4" primaries, 2" secondaries.
So obviously these don't fit our cars. But it's the right concept. If one could imagine the short version with a 3" collector, twist it & bend the shape to fit, would be the kind of design we will need.
Any comments on the sizing? I guess the first thing will be to get hold of a stock exhaust manifold gasket & check the port sizes. But my memory did serve me well, the "standard" size for 4-1 headers on the big capacity V8's in Oz is 1-7/8" primaries, to a 3" collector.
Looking for off the shelf bits to try & cobble something together, I came across Burns Stainless. They have pre-sized merge collectors, which were sized using thier Burns Stainless LLC - X-Design Exhaust Header Design Program the sizes don't quite match up when trying to put together a 4-2-1 header
Primary-Secondary......Secondary-Collector
1-1/2" to 2-1/8".........2-1/8" to 3"
1-5/8" to 2-1/4".........2-1/4" to 3-1/4"
1-7/8" to 2-5/8".........2-5/8" to 3-3/4"
Much bigger than the ones Down Under (I don't think that's ever been said before )
Another interesting link here How To Calculate Muffler Size and Exhaust Pipe Diameter | Exhaust Videos
We run twin systems, so how does it look for pipe size;
I'm going to assume flywheel HP is shown in the table e.g. my XJR runs a twin 2-1/4" system, and was making 400HP from the factory. Looks about right.
1-5/8" primaries should be good for 700HP, 1-3/4" might be a bit of an overkill. The Burns combo of 1-5/8" to 2-1/4" to 3-1/4" looks good. Just a matter of getting it to fit...
Will take time, but at least it's clean what direction to go in now.
#25
FERLITO Racing
hi,
hear the Jaguar XF-R 4.2 with hi-perf exhausts and hand made manifolds of Ferlito Racing Team!!
Really HOT!
https://www.facebook.com/video.php?v...42&pnref=story
I was at their workshop. their racing exhaust manifolds were developed along with new engine mounts that allow you to have more space to make manifolds.
you can also listen to the hiss of the supercharger (Eaton M112 series) with new crankshaft pulley 180mm
hear the Jaguar XF-R 4.2 with hi-perf exhausts and hand made manifolds of Ferlito Racing Team!!
Really HOT!
https://www.facebook.com/video.php?v...42&pnref=story
I was at their workshop. their racing exhaust manifolds were developed along with new engine mounts that allow you to have more space to make manifolds.
you can also listen to the hiss of the supercharger (Eaton M112 series) with new crankshaft pulley 180mm
Last edited by User 070620; 02-17-2015 at 08:08 AM.
#26
That sounded great. I have no experience with putting headers on the jaguar SC motors. I can tell you however with my v6 ford supercharged engines not much if any gain was noticed on the 3.8 motors with full length or shorty type headers produced by Kooks. Making 400 plus rwhp with a 2" exhaust manifold outlet...Swapping to headers with a 2.5"-3" outlet really not doing much. I would never have believed it if I hadn't seen it myself. I realized that with a NA motor you are dealing with scavenging and with an SC engine you really aren't however I thought the 2" outlet would have been mega restrictive. In the SC engines Its more about restriction than anything. Unfortunately I'm not willing to experiment with getting headers built for my xkr even having a contact to do so in NY. Maybe some extremely wealthy person with a love for this car...But I am thinking this would take many different variants to find the perfect compromise.
The following 2 users liked this post by XxSlowpokexX:
Panthro (05-29-2016),
User 070620 (02-18-2015)
#27
So I haven't given up on this one...
The biggest issue from what I can tell is space, there just isn't much room to get the manifolds in there. Good example in this pic.
You can see how the stock manifolds sit right below the heads. If they "have" to be like that, then there isn't much hope...
BUT
Just for interests sake, these are the "design" of header that we would have to look at, kind of funny that a Chev GenIV LS2 would need the exact same branching as our AJ-V8's
Left side
Right side
Check out the branching, exactly the same as what we need.
These ones are made by Pacemaker (an Aussie company, not sure if made local or in China) for the Holden Commodore running a 6.0L N/A V8. They are short like that to keeps the cats in the factory position.
Sizes of the "Short Tri-y" in the pics above are are 1-3/4" primaries, 2" secondaries, 2-1/2" collector with flange. My gut feeling selection would be a 3" collector for the AJ-V8's looking for >600HP.
Pacemaker do make a "Long Tri-y" with the same primary & secondary sizes, but a 3" collector.
The long version with 3" collector. Also 1-3/4" primaries, 2" secondaries.
So obviously these don't fit our cars. But it's the right concept. If one could imagine the short version with a 3" collector, twist it & bend the shape to fit, would be the kind of design we will need.
Any comments on the sizing? I guess the first thing will be to get hold of a stock exhaust manifold gasket & check the port sizes. But my memory did serve me well, the "standard" size for 4-1 headers on the big capacity V8's in Oz is 1-7/8" primaries, to a 3" collector.
Looking for off the shelf bits to try & cobble something together, I came across Burns Stainless. They have pre-sized merge collectors, which were sized using thier Burns Stainless LLC - X-Design Exhaust Header Design Program the sizes don't quite match up when trying to put together a 4-2-1 header
Primary-Secondary......Secondary-Collector
1-1/2" to 2-1/8".........2-1/8" to 3"
1-5/8" to 2-1/4".........2-1/4" to 3-1/4"
1-7/8" to 2-5/8".........2-5/8" to 3-3/4"
Much bigger than the ones Down Under (I don't think that's ever been said before )
Another interesting link here How To Calculate Muffler Size and Exhaust Pipe Diameter | Exhaust Videos
We run twin systems, so how does it look for pipe size;
I'm going to assume flywheel HP is shown in the table e.g. my XJR runs a twin 2-1/4" system, and was making 400HP from the factory. Looks about right.
1-5/8" primaries should be good for 700HP, 1-3/4" might be a bit of an overkill. The Burns combo of 1-5/8" to 2-1/4" to 3-1/4" looks good. Just a matter of getting it to fit...
Will take time, but at least it's clean what direction to go in now.
The biggest issue from what I can tell is space, there just isn't much room to get the manifolds in there. Good example in this pic.
You can see how the stock manifolds sit right below the heads. If they "have" to be like that, then there isn't much hope...
BUT
Just for interests sake, these are the "design" of header that we would have to look at, kind of funny that a Chev GenIV LS2 would need the exact same branching as our AJ-V8's
Left side
Right side
Check out the branching, exactly the same as what we need.
These ones are made by Pacemaker (an Aussie company, not sure if made local or in China) for the Holden Commodore running a 6.0L N/A V8. They are short like that to keeps the cats in the factory position.
Sizes of the "Short Tri-y" in the pics above are are 1-3/4" primaries, 2" secondaries, 2-1/2" collector with flange. My gut feeling selection would be a 3" collector for the AJ-V8's looking for >600HP.
Pacemaker do make a "Long Tri-y" with the same primary & secondary sizes, but a 3" collector.
The long version with 3" collector. Also 1-3/4" primaries, 2" secondaries.
So obviously these don't fit our cars. But it's the right concept. If one could imagine the short version with a 3" collector, twist it & bend the shape to fit, would be the kind of design we will need.
Any comments on the sizing? I guess the first thing will be to get hold of a stock exhaust manifold gasket & check the port sizes. But my memory did serve me well, the "standard" size for 4-1 headers on the big capacity V8's in Oz is 1-7/8" primaries, to a 3" collector.
Looking for off the shelf bits to try & cobble something together, I came across Burns Stainless. They have pre-sized merge collectors, which were sized using thier Burns Stainless LLC - X-Design Exhaust Header Design Program the sizes don't quite match up when trying to put together a 4-2-1 header
Primary-Secondary......Secondary-Collector
1-1/2" to 2-1/8".........2-1/8" to 3"
1-5/8" to 2-1/4".........2-1/4" to 3-1/4"
1-7/8" to 2-5/8".........2-5/8" to 3-3/4"
Much bigger than the ones Down Under (I don't think that's ever been said before )
Another interesting link here How To Calculate Muffler Size and Exhaust Pipe Diameter | Exhaust Videos
We run twin systems, so how does it look for pipe size;
I'm going to assume flywheel HP is shown in the table e.g. my XJR runs a twin 2-1/4" system, and was making 400HP from the factory. Looks about right.
1-5/8" primaries should be good for 700HP, 1-3/4" might be a bit of an overkill. The Burns combo of 1-5/8" to 2-1/4" to 3-1/4" looks good. Just a matter of getting it to fit...
Will take time, but at least it's clean what direction to go in now.
Recently I have become fascinated by how the exhaust manifold/header design can completely transform the sound of a car. I'm attracted to high pitched race car engine sounds in particular but baritone muscle cars sound pretty amazing too.
Changing the cat back system on Jag V8s has limited possibilities, it'll be louder with more bass or too loud and boomy. Even if there isn't a major power gain from fitting tubular exhaust manifold headers I still think it's worth the effort and cost for the enhanced sound quality.
Check out my YouTube playlist focused on high pitched engine sounds: https://youtube.com/playlist?list=PL...pfceLltusnYenh
This XJS V12 has equal length headers fitted, that's why is sounds like a Ferrari.
Burns Stainless provide advice for header design, you can fill in a form with your engine's spec and they'll get back to you with their recommended sizes and parts you'll need: https://burnsstainless.com/pages/race-engine-spec-form
Does anyone know where I can find all the AJV8 engine data they ask for?
It would be interesting to hear what they say.
https://www.jaguarforums.com/forum/x...terest-176950/
Caldoofy's system is one of two custom header designs I have seen since you made this post:
https://www.jaguarforums.com/forum/x...terest-176950/
It looks like there is just enough space for two parallel runners following a compact path, but if you want the high pitched, equal length sound it might be impossible within the cylinder head/ chassis zone, perhaps long tubes down to the end of the down tubes, might work, smaller diameter high flow cats look like they would fit after the bend without protruding below the floorpan.
With the popularity of 3D printers, it has become simpler to clip a bunch of 3D printed, measured plastic tube segments together to work out the optimum routing for the runners, it's a bit like Lego but each part features the tube length, bend radius, rotation increment marks and cut angle printed onto it. Expect to wait a few weeks of constant 3D printing until you collect enough segments.
https://www.thingiverse.com/thing:1649639
You can buy ready made parts like this but their price make the sets reserved for professional fabricators:
https://www.trick-tools.com/Icengine...ng-Systems-864
Last edited by SABARRAS; 02-27-2021 at 11:37 AM.
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