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Header question for all


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Mark, all:

 

Would less talent be needed to build the exhaust if the headers were made to clear the pan in the first place?

 

It seems as though those that would spend bigger money for full length headers (than block huggers) may also have a Canton pan with the kickouts. I think any long tube headers should be designed to fit the Canton pan.

 

If that's the case, I see no reason that the primaries should be any lower than the Canton Pan (7" from the oil pan rail). They may have to be a bit lower towards the aft end of the block, but the trans/bellhousing is low there anyway, and the pipes may need to go lower (not more than needed!) there.

 

Another fitment issue is the bellhousing. I'm using the Lakewood bellhousing, which is designed for the larger flywheel. It's a beast. Having the headers point past this (which I think is the largest) bellhousing and the largest auto trans (700R4?) is also a must.

 

No sense having these designed if they won't fit the largest majority of applications.

 

That being said, I think they should be designed for 1-7/8" primaries, and have another (easier to build) version with 1-3/4". 1-5/8" would be about as small as they should go, and 2" seems beyond what anyone needs. When you go past 1-3/4", many people feel you need to go to the 2-piece Hooker or Stahl head flanges. That can cause fitment issues, since it pushes the tube beginning out further from the head.

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Pete,

 

Those headers are the holy grail. If some one will build them, I'm in. Full length headers that would clear the canton pan and your type bell housing should work with anything else out there. Lets make it happen.

 

Mark

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I bought the 5205's uncoated and trial fitted the engine/tranny this weekend.

I'll take pictures of the clearance issues and post them tonight. Basically the header collectors need to be tweaked down and in a little. I have the Canton pan and I am planning on cutting the passenger wing down some and welding up the oil level sensor hole on the driver side. The header rests on the passenger wing and is right next to the oil level sensor plug. Then I will be taking the car to a friend's exhaust shop and heating and bending the headers to where I like them. Then I'll send them back to get re-coated. The steering shaft seems to clear, but not by much. For installation position reference... When I installed the motor, I did not slot the mounting holes and I am using the JTR engine mount brackets.

 

Jody

 

Here's a pic of the pan and headers from the front. The picture looks lower because of the picture angle.

front%20header-pan%20clearance.jpg

 

The driver side collector is very close to the T56 slave cyl bump.

collector-t56%20slave.jpg

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Thank You Pete! That is what I wanted to hear. I also have a Lakewood bellhousing and it IS a beast, as you said. I will end up cutting the bottom off and plating it. I really wish someone made a smaller bell housing for a 153 tooth, as I am sure you do too (and as safe of course).

Joshua

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Well I sacreficed one of my headers to Jim's project today since the right side header we ordered got a little TOO hot in the process of trying to fit it around and collapsing the pipe at the pan... That tubing is WAY THIN Jody so be careful when you guys heat up the pipes.

 

I agree that it should be built around the Lakewood and Canton pan.

 

Mike

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Mike, thanks for the heads up on the thin pipe. I don't think I need to move the collectors much. Heating 4 pipes well might take 2 torches to prevent a kinked pipe.

The passenger side faces the fuel/brake lines and the driver side faces the foot-well corner.

 

Jody

 

Here are a couple more pictures of the collector location.

pass%20collector.jpg

both%20collectors.jpg

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Just got off the phone yesterday with the guys working on Jims S&S header/ Canton RR Pan/ Lakewood Bellhousing combo... It is giving them FITS... the external Slave is interfering with the header fitment. The clutch for is interfering with the header fitment... Ton of frustration on their end in making all this work for the sake of HOW MUCH (?) extra HP. Damn I wish someone would make something like TIM made and SELL it in mass production... I'd have two sets sold YESTERDAY!

Mike

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Mike,

Maybe if you ask Bartman (who is now the proud owner of those headers), he can send them to an exhaust fabricator to have them copied. I'm sure that with the right bending equipment, they could be done much nicer and more compactly than I did them......

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After reading through all of the literature from 'Headers by "ED"' (I ordered his entire literature package and the CD), I'm guessing I'll need 1-7/8" primaries with 3 1/4" collectors. According to his literature, a V8 making 480-580 hp should use 1-7/8" primaries (at least 34" long) and anywhere from 3" to 3 1/2" collectors.

 

Oh yeah, let's not forget getting these designed so that all straight and angle plug variations will have plenty of clearance. It can be done, it just has to be considered in the design.

 

Another issue with the SBC is port shape and size. Lots of options there...I'm wondering if we should have them designed with the Stahl type flanges welded to the headers, and use the head mounted adapter flange to make up some of the difference in port shape and size.

 

I've VERY close to ordering a DIY header kit from Headers by ED. I figure if I get the version of the kit with the pipe stubs already welded to the flange, with the correct flange shape/size, and build them to the specs he suggests through his header design service, I could build a set that could be copied by some company. I'd probably build them by getting them all tacked together and take them to a TIG pro to have finish welded.

 

One thing is for sure. The 1-5/8" block hugger is NOT a header, it's a cheap and easy way to pipe the exhaust to the mufflers.

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Pete,

Thanks for the contact of "Headers by Ed". They certainly carry a lot exhaust parts. I almost fel on the floor though when I saw the price of their header kit. Wow are they expensive (at least it seems like it to me). The header flanges that come stock are 1/4" also unless you upgrade.

Would it be better to buy a premade header (Possibly Hedman, Hooker, etc) and modify them. I am thinking about cutting the headers apart to recover the flange with prewelded stubs. Then most of the tubing can probably be reused also. Same with the collectors. I am sure that the need to purchase additional J and U bends will arise, but maybe by only purchasing one of two, it will work.

I put my Hedman Chevy Truck headers in my engine bay (with the engine mounted of course) and it looks like they are very cose to fitting. It appears that the interference problem is with the collector/one tube to T/C rod mount (of course). Maybe the collector can be rotated with a little cutting, rewelding and made to fit. The Hedmans were only ~$120. Seems like for ~$200-250, the work would be minimized (over a full header kit with unwelded stubs) as would the cost. Maybe the results are not what you are looking for though...

Just some thoughts,

Joshua

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Joshua, that would certainly be alot cheaper - using the hedman headers and hacking.

 

I guess I've been won over a bit by Ed Henneman's literature, etc. Being an anal retentive mechanical engineer, I find what Ed has to say about headers really resonates with me. His view is that most headers are just plumbing to get the exhaust to the mufflers. He makes a vaild point that spending many thousands of dollars on building an engine from the point of air and fuel entry to the exhaust ports seems a bit silly if you are leaving performance on the table (or even making it worse than manifolds might give you) by not designing a header for the task. Or at least using one that is has a decent design.

 

Then again, it's not like I have the time to build a set of custom headers to be able to get my 406 on the road by the ZCCA convention...

 

BTW, what size or the primaries and collectors on the truck headers?

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My solution to the Canton Oil pan and S&S headers.

After stripping most of the paint off of the oil pan... I cut the oil pan wing down on the passenger side and cut the oil level sensor off on the driver side. The inner oil control flap is still completely functional. Then instead of heating and bending the headers, ( since Mike Kelly collapsed a header heating it to bend it ) I cut both collector flanges at an angle, spun the flange around and rewelded it on pointing in the right direction.

 

079.jpg

 

080.jpg

 

After re-welding the header flange.

081.jpg

 

Jody

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Pete,

I understand what it is like to be an anal ME. Others around me usually don't though. Alwell.

I have done some research on headers in the past, and the result was basically that many people don't agree on what optimal is. I just want a good clean way to the exhaust from my heads to the mufflers. Without significant work and dyno testing I feel like I may leave a few horses behind, but that is the price I am willing to pay. Yes, I have a lot of money in my engine, and would like to get out as much as I can, but I also realize that there are tradeoffs. Personally, I would rather mine left 5 Hp behind and looks great instead. That is just me though. I would love to see an excellently designed header though!

My truck headers primaries are 1 5/8" I believe. They are for an 81 Chevy 4x4 SBC. I used them on my 400 when I had the ruck with 2 1/2" dual to flowmasters. While maybe not optimal, they were a lot better than the stock iron manifolds.

I am looking at using 1 5/8" or 1 3/4" for my headers. The diameter should affect Torque a little, and of course top end HP. I would rather have better lower end torque though, plus these should be easier to route and possibly look better. I also plan to use 2 1/2" for the rest of the system, possibly 2 into 1 behind the tranny. I will have to work on that setup though.

Jody,

Those look great! Looks like they fit real nice. Do you have to take the engine out to install them, or can you get them in with everything mounted? Also, how much lower than the frame rails do they hang? Do you think that the clearance will be a problem?

Joshua

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Oh, Pete, I meant to also add that I think you can get some flowtech (holley brand, cheap line) headers for the SBC for ~$90 from Autozone. I have never used them, but maybe that would be a good start for the flanges and collector?

Joshua

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Jody' date='

Those look great! Looks like they fit real nice. Do you have to take the engine out to install them, or can you get them in with everything mounted? Also, how much lower than the frame rails do they hang? Do you think that the clearance will be a problem?

Joshua[/quote']

 

Joshua,

Since I am in the test fitting stage, there is nothing but the motor and hollow transmission (spare T56 case) in the car. I lifted the motor off the mounts about 2" and both headers drop in easily. I doubt that they'd go in otherwise. (but I really didn't try)

As far as clearance, I don't plan on lowering the car much, but the low spot of the exhaust is going to be the front of the collectors. I have not put the car on the ground yet with the engine weight. I'll probably do that this week and adjust the coil-overs. I have cut-outs on both sides of my transmission mount for duals so the rest of the exhaust will tuck up fine.

 

Jody

 

066.jpg

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I don't recall mine sitting that low. Jody, Are you using the spacer between the front cross member and the chassis (JTR pieces)?

 

Jolane, I think that with any motor that is going to flow above 400HP, you really need increased volume and primaries below 1 3/4 will hurt power significantly across the range. I'd Love to get some 1 7/8th headers, but the only way I see that happening is to buy a kit or pay someone to fabricate them...

 

Oh well...The joy of stuffing a Chevy into a Datsun, No?

 

Jody, I was getting ready to start cutting my pan up... Glad you posted pics... I now see what I need to do!

Mike

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Mike,

 

I am using the body spacer (stock JTR ). Once I get the car on the ground I'll re-evaluate the height. If too low, maybe I'll go with a little larger spacer and raise the motor a little.

It's a shame to know that they may still drag.

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I'm not using the spacer between the engine crossmember and frame rails - I removed them to get a better angle on the transmission output shaft. Leaving them out raises the engine mounts relative to the body, so it makes the output shaft angle a bit more pointed down going front to back, better matching the differential pinion angle (after making adjustments to that too).

 

1-5/8" long tubes are going to start killing top end power above 400hp, according the the Headers by Ed advice. I want 1-7/8" as well, and will probably end up making a set, next winter if not sooner.

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