I myself was thinking that #8 is going to hit that cage bar
but the movement out where the collector goes though the little hole it has, will be a problem maybe too.......
CK5
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'72 K5 - Greg's @MightAsWellK5 Build
- Thread starter Greg72
- Start date
This is the build description. I will improve this later. (GB)
but the movement out where the collector goes though the little hole it has, will be a problem maybe too.......
2015.07.02 - UPDATE! - HEADER IS NOW 15% COMPLETE...!!!! 
Let me add a new tip to my previous list....
Rule #5: Never brag about how much tire clearance you've got around the headers.
What a shame. I got the 4th tube installed last night and the headers were looking totally bitchin'
I was really enjoying my victory, so I decided to bolt the wheel back on and jack the front axle off the ground so I could steer the tires full-left and full-right. (Remember, the suspension is also at "Full Bump" right now...the struts are completely bottomed-out)
Swung the tire around and got this:
THAT SUCKS!!!
The tire hits the lower outside tube (#4 Primary) but looks like it would clear just about everything else if it were removed. So basically the tire needs about 2" more room (the diameter of the primary tube) to hit the steering stops.... and probably a bit more in reserve for when the driver's side tire is drooping-out and causing the PS tire to "lay over" at the top.
My 5Lb Bag already has about 10Lbs of stuff in it, and there really aren't any simply ways to move that one tube without creating a visual mess of the area.
The collector was pushed as close to the framerail as possible when I first tacked it into place. There is a torsion/cab support assembly that runs down through that area, and into the #1 Cab Support bolt area..... you can see it here:
(Laying on the floor looking straight up at the exhaust. Front of the truck is at the top, back of the truck is at the bottom of photo)
So I decided to re-write some of the 1972 zoning laws and used the powers of eminent domain (spotweld cutter and Sawzall) to claim that area for the greater good of the exhaust collective.
Honestly, it wasn't contributing much lately anyway.... the majority of that long torsional support had already been chopped out from underneath, and only a small section containing the cab support mount and cowl support brace was left intact. Bascially, I just wrote myself another "I.O.U." for some floor/cowl bracing.... but that was going to have to happen anyway.
The end-result was this. Check out all that luxurious "extra" space we've got now!!!
I'd guess there's around 4" of extra space available now, and hopefully this will allow me to keep MOST of my current header design intact, and just shorten up a few tubes to pull the whole thing in tighter to the framerail.
The other benefit is that since the support bracket for the #1 cab support is removed also, there is an even larger "pass through" hole for the collector now. It might end up being OVAL instead of round, but it should definitely have plenty of room..... and hopefully enough clearance so that it doesn't bang around when the engine rocks on the motor mounts.
We'll see.
-G
Let me add a new tip to my previous list....
Rule #5: Never brag about how much tire clearance you've got around the headers.
What a shame. I got the 4th tube installed last night and the headers were looking totally bitchin'
I was really enjoying my victory, so I decided to bolt the wheel back on and jack the front axle off the ground so I could steer the tires full-left and full-right. (Remember, the suspension is also at "Full Bump" right now...the struts are completely bottomed-out)
Swung the tire around and got this:
THAT SUCKS!!!
The tire hits the lower outside tube (#4 Primary) but looks like it would clear just about everything else if it were removed. So basically the tire needs about 2" more room (the diameter of the primary tube) to hit the steering stops.... and probably a bit more in reserve for when the driver's side tire is drooping-out and causing the PS tire to "lay over" at the top.
My 5Lb Bag already has about 10Lbs of stuff in it, and there really aren't any simply ways to move that one tube without creating a visual mess of the area.
The collector was pushed as close to the framerail as possible when I first tacked it into place. There is a torsion/cab support assembly that runs down through that area, and into the #1 Cab Support bolt area..... you can see it here:
(Laying on the floor looking straight up at the exhaust. Front of the truck is at the top, back of the truck is at the bottom of photo)
So I decided to re-write some of the 1972 zoning laws and used the powers of eminent domain (spotweld cutter and Sawzall) to claim that area for the greater good of the exhaust collective.
Honestly, it wasn't contributing much lately anyway.... the majority of that long torsional support had already been chopped out from underneath, and only a small section containing the cab support mount and cowl support brace was left intact. Bascially, I just wrote myself another "I.O.U." for some floor/cowl bracing.... but that was going to have to happen anyway.
The end-result was this. Check out all that luxurious "extra" space we've got now!!!
I'd guess there's around 4" of extra space available now, and hopefully this will allow me to keep MOST of my current header design intact, and just shorten up a few tubes to pull the whole thing in tighter to the framerail.
The other benefit is that since the support bracket for the #1 cab support is removed also, there is an even larger "pass through" hole for the collector now. It might end up being OVAL instead of round, but it should definitely have plenty of room..... and hopefully enough clearance so that it doesn't bang around when the engine rocks on the motor mounts.
We'll see.
-G
It is too bad there isn't more trucks like yours out there.. Most people would have given up. The sheer level of dedication you show towards your end goal is simple amazing. Keep it up!
You don't want any backpressure, which is why I cringe when people use that term. Too large of primaries may lose velocity and hurt performance but you definitely do not want any backpressure. With that said I think he is fine with a 3" collector and dual exhaust for that engine as well, I agree with you. 3.5" wouldn't hurt anything but it probably won't gain much either.
I think he should stick with his 4:1 with duals, better than 8:1 in my opinion, unless he is going to go with at least a 4.25" pipe on the single. That would be the equivelant ID area of dual 3". 8 to 1 could be very restrictive too close to the hot engine exhaust if its not done correctly. The further away the exhaust travels and cools from the head, the less critical the flow is.
If you think space is tight now.... imagine trying to find room somewhere underneath the truck to merge the exhaust into some kind of 8-1 configuration!!!
I can't even sneak a simple "X" or "H" style balance pipe into this truck.....ain't no WAY I'm going to be able to do anything fancier than a simple dual-exhaust setup. Odds are close to 100% that I'm going to have to dump them out the sides (near the rear tires) too.... there doesn't seem to be any place available for me to get the exhaust pipes inside the framerail as I move further back....
-G
I think you will be perfectly happy with your true dual 3" Greg. I run dual 3" and it woke the engine way up vs the smaller pipes I had on it originally from the small block. Sounds better too, it sounds deeper tone and less "poppy" sounding. Short tailpipes will make it sound even deeper tone, you will like it.
Now if you even plan to stroke that thing to a 540, then a dual 3.5" might be an option.
Now if you even plan to stroke that thing to a 540, then a dual 3.5" might be an option.
I think you will be perfectly happy with your true dual 3" Greg. I run dual 3" and it woke the engine way up vs the smaller pipes I had on it originally from the small block. Sounds better too, it sounds deeper tone and less "poppy" sounding. Short tailpipes will make it sound even deeper tone, you will like it.
Now if you even plan to stroke that thing to a 540, then a dual 3.5" might be an option.
Got any video clips of that motor running under load? I'd love to hear it.
-G
Most of the video I have under load is sand drag races with other engines mixed in as well, not very good sound quality. My BIL just got a new go-pro, maybe I can get some more videos when we go back later this summer.
You're right, I shouldn't of used that terminology.
I'd run a 3" collector, maybe run one that was a touch longer as well typically those pull the curve down.
Greg, shame on the headers and tire wanting to re joice in marriage, I was going to suggest coming up with everything and dropping it down the firewall, but in lookin at it, tire still would of made contact.
Looking good so far, I building a exhaust system for a tvr this week, it's all 2" stainless from the header back... Hahah cutest little exhaust I've ever done!
Been on vacation a couple of weeks and am catching up here. Isn't this done yet?
Never posted in this thread, but have been watching it for awhile.
I saw this posted on pirate and thought I'd drop it in for some inspiration.
I saw this posted on pirate and thought I'd drop it in for some inspiration.
Never posted in this thread, but have been watching it for awhile.
I saw this posted on pirate and thought I'd drop it in for some inspiration.
Doc Octopus makes headers now?
-- A
Sonofa..... Beat me to it...
K20Chevrolet
1/2 ton status
Greg, for the heat isue, Lizzard skin makes some nice spray on insulation for both sound and heat. That might ba en option, at least on the inside of the floar board, to help keep the heat out!
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bp71k5
3/4 ton status
Looking like the lego tube pieces are turning out to be a good idea. That would have stunk to welded up a bunch of tubes and find that out.
Brian,
No doubt!
I am glad that I spent the 10 hours or so that it took to cut all those segments and sleeves.... It gave me some valuable practice working with exhaust bends so it doesn't bother me that I spent so many hours on it. One way or the other, I was going to have to pay that tuition.
Being able to rotate each segment individually and change the end-point of the primary tube in 3D space was every bit as satisfying as I imagined it would be.... And given how messed-up the clearances are now, I get another chance to have all that "fun" again!
-G
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