critique my DIY custom headers
#1
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critique my DIY custom headers
I've been working on my fox swap and am designing my own headers to fit the chassis. I'm designing/building my own headers because none of the engine swap headers are going to work due to the relocation of the engine as far back and as down low in the chassis as possible. Also, I just like building stuff.
In order to do a bunch of header design iterations without wasting alot of money on mandrel bends, I just went and made 3D CAD models of the necessary components in Solidworks. All the bends are on a 3" center line radius and are 1 7/8" diameter. The collector is a 4 into 1 with a 5" long merge with Cone Engineering star, 2.5" diameter at the venturi 4" long reverse cone to a 3" collector. The overall collector length after the merge can be however long it needs to be, although since I will be running a 3" exhaust and a 3" collector, the length of the collector probably becomes irrelevant.
The closest in length I could get the primaries were:
primary 2 = 32.8 inches
primary 4 = 30.5 inches
primary 6 = 31 inches
primary 8 = 27.8 inches
My greatest concern is that my primaries are going to be too close the the starter and will fry the starter. I've got just under 1/2" of clearance from the starter motor to the primaries, and just under 1/2" of clearance from the primaries to the solenoid.
How close do the "standard" fbody headers come to the starter and solenoid? Thanks.
There are more pictures in my build thread if you are interested:
https://ls1tech.com/forums/conversio...l#post17932731
In order to do a bunch of header design iterations without wasting alot of money on mandrel bends, I just went and made 3D CAD models of the necessary components in Solidworks. All the bends are on a 3" center line radius and are 1 7/8" diameter. The collector is a 4 into 1 with a 5" long merge with Cone Engineering star, 2.5" diameter at the venturi 4" long reverse cone to a 3" collector. The overall collector length after the merge can be however long it needs to be, although since I will be running a 3" exhaust and a 3" collector, the length of the collector probably becomes irrelevant.
The closest in length I could get the primaries were:
primary 2 = 32.8 inches
primary 4 = 30.5 inches
primary 6 = 31 inches
primary 8 = 27.8 inches
My greatest concern is that my primaries are going to be too close the the starter and will fry the starter. I've got just under 1/2" of clearance from the starter motor to the primaries, and just under 1/2" of clearance from the primaries to the solenoid.
How close do the "standard" fbody headers come to the starter and solenoid? Thanks.
There are more pictures in my build thread if you are interested:
https://ls1tech.com/forums/conversio...l#post17932731
Last edited by usdmholden; 01-07-2014 at 08:42 AM.
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I also plan on getting them coated, but it's alot easier to make a change to routing now before I start cutting and welding, should it be necessary.
Thanks
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How do the primaries lengths and number of bends compare to others?
I've done a bunch of research comparing the LG Corvette headers, 1 3/4 vs 1 7/8, and primary lengths and collector design, since they appear to work pretty well and have been reviewed a whole bunch. However I can't tell how long a typical fbody header is compared to a Corvette header, or how much difference there is from shortest tube to longest tube on any of them.
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It is different than the various CAD models available for the LS starters, so I had to build my own accurate model of it to make sure the headers cleared.
What starter is on the left? Thanks.
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#9
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I would try and make them so you can get the starter out without taking the header off.
With my 2 to 2.125 I am not close to the starter but I have to remove 1 tube to get it out of the car.
The heat shield is only going to help not prevent issues with the header that tight.
Tim
With my 2 to 2.125 I am not close to the starter but I have to remove 1 tube to get it out of the car.
The heat shield is only going to help not prevent issues with the header that tight.
Tim
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I would try and make them so you can get the starter out without taking the header off.
With my 2 to 2.125 I am not close to the starter but I have to remove 1 tube to get it out of the car.
The heat shield is only going to help not prevent issues with the header that tight.
Tim
With my 2 to 2.125 I am not close to the starter but I have to remove 1 tube to get it out of the car.
The heat shield is only going to help not prevent issues with the header that tight.
Tim
There should not be any heat rising off the header and hitting the starter, the only heat from the header to the starter should be radiating sideways, rather than rising onto the bottom of the starter. Not sure if this makes sense.
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The T56 and bellhousing also came from grabcad, but originated on ls1tech. However, I doubt some of its accuracy. The T56 on grabcad came with other parts in the same STEP file, and when I compared the other parts to measurements from the*same* physical part, they were far off, so I doubt the T56 and bellhousing models. Once I am done measuring and plotting the driver's side of the chassis, I am going to pull the drivetrain again and re-do my T56 and bell housing model so I can correct any design problems before I actually build the headers. There is the possibility that I am comparing one part to a different part, the effort to build the model was large.
There is also a Corvette LS6 edrawings model from the actual GM CAD files floating around which I took measurements from (relative to crank center line, block face, bell housing face, etc) and built my own Solidworks LS1/LS6 parts. I also referenced an actual LS1 long block on the stand to compare the LS6 edrawings model to reality. I did this before I found the LS3 GM model. After finding the GM LS3 model, I pretty much just use it, because it's fully detailed, and the external physical features are nearly interchangeable.
I believe this is the GM model with some customization:
http://grabcad.com/library/chevy-ls3-6-2l-1
Not really dimensionally accurate on several components (starter, oil pan, water pump) but perhaps they are different components than I compared them to (LS3 vs LS6 vs LS1):
http://grabcad.com/library/ls3-t56-e...smission-model
https://ls1tech.com/forums/conversio...l-started.html
The LS6 edrawings model used to be here, but now it's gone? I have a copy.
http://www.spectrum5racing.com/Proje.../ultimals6.htm
#13
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I went through building my own headers not too long ago (last summer). I ended up using a PowerMaster 9509 starter to have enough space for the 1 7/8" headers. It's about 1/2" shorter than the factory starter and you can clock them to any position. Might buy you some extra space.
Even with the smaller starter, there is very little clearance to the headers. I've got it wrapped up pretty well and the headers are coated. No heat issues so far.
Also, where are you getting your pipe from?
Even with the smaller starter, there is very little clearance to the headers. I've got it wrapped up pretty well and the headers are coated. No heat issues so far.
Also, where are you getting your pipe from?
Last edited by MX6.0; 01-08-2014 at 09:19 AM.
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I went through building my own headers not too long ago (last summer). I ended up using a PowerMaster 9509 starter to have enough space for the 1 7/8" headers. It's about 1/2" shorter than the factory starter and you can clock them to any position. Might buy you some extra space.
Even with the smaller starter, there is very little clearance to the headers. I've got it wrapped up pretty well and the headers are coated. No heat issues so far.
Also, where are you getting your pipe from?
Even with the smaller starter, there is very little clearance to the headers. I've got it wrapped up pretty well and the headers are coated. No heat issues so far.
Also, where are you getting your pipe from?
I bought the 1 7/8" deluxe builder kit from Megs / Cone Engineering. It probably has more bends than I need:
p/n TU-HBK-1875-MS-2
http://www.coneeng.com/pdf/Header%20...ends%20PDF.pdf
Collector kit:
p/n CK-CL4-188-MS
http://www.coneeng.com/pdf/4-1%20Col...Kits%20PDF.pdf
#15
What do you figure your ground clearance will be with these headers? Very interested, as I am building a 63 mercury meteor with a maximum motorsports sn95 front suspension. Thought about making my own headers, but I am going to try a test fit with some cheap used 1 3/4 F body headers that I picked up. The motor will be as far back and down as possible in my car as well, and I am concerned about ground and steering shaft clearance.
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What do you figure your ground clearance will be with these headers? Very interested, as I am building a 63 mercury meteor with a maximum motorsports sn95 front suspension. Thought about making my own headers, but I am going to try a test fit with some cheap used 1 3/4 F body headers that I picked up. The motor will be as far back and down as possible in my car as well, and I am concerned about ground and steering shaft clearance.
Measuring in the CAD system, the bottom of the lowest primary will sit about .9" below the bottom surface of the fbody oil pan. The lowest point of the header is the vband clamp, and it is 1.2" below the lowest point of the oil pan bottom surface.
HOWEVER, if the engine were level, the bottom surface of the oil pan sits at least an inch above the lowest bottom of the cross tube on the MM k member, which means the primaries are about .1" above the lowest point of the k member, and the bottom of the vband clamp is .2" below the lowest point on the k member.
Since the engine is not level, The vband clamp is about 1.2" below the bottom of the MM subframe connectors, which means my subframe connectors are effectively at the same height as the bottom of the fbody oil pan. If I go to header clamps then I think the header clamps will sit about .875 below the bottom of the subframe connector. For reference, the lowest point on the T56 is about .5" below the bottom of the subframe connectors. Which means the headers will only be about 3/8" lower than the drivetrain.
Also, in my model there is only about .2" clearance between the back of the block and the firewall, and I hammered the firewall back on the passenger side by at least .75" before I made the CAD model. In real life, there is more clearance on the pass side because the firewall pulls away from the engine towards the center where the trans tunnel is. My floor pan model is worst case scenario.
There are pictures of the oil pan and floorpan in my build thread. In the build thread I replaced the fbody oil pan with a Holley 302-2 because I wrecked the fbody oil pan.
Take into account your firewall in the Mercury is going to be alot different than the firewall in the fox Mustang as well as the steering shaft.
Also, the motor mount stands on the MM 4.6L k member (what I am using) are very large compared to other k members. The #1 and #2 primary tubes will have to move back at a large angle to clear the MM k member. You can see it in the jpeg I attached.
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