A header question with a twist

[MikeB]

Hey Tim, thanks for your response. The reason I brought up 4WD is I think those trucks had the engine mounted in the rear position. The space between the frame rails widens the farther back you go, meaning more header clearance.

[YellowK5]

I just put a set of Headmans on my 71 C20 350 small block with automatic. engine in the forward position. They are close but fit well. Had them Jet hot ceramic coated

[MikeB]

Originally Posted by YellowK5

I just put a set of Headmans on my 71 C20 350 small block with automatic. engine in the forward position. They are close but fit well. Had them Jet hot ceramic coated

What part number are the headers, and what did the coating cost?

I have always heard that Jet Hot is one of the best.

[YellowK5]

I need to check the number ..the coating was 150 but we get lots of it done at our shop so I get a good deal

[MikeB]

Just went to Jet Hot's website for a quote. It was $433.90 for long tubes.

['68OrangeSunshine]

I looked at the Jet Hot brochure and was impressed, but didn't have the long cash to make that happen. I found a product in the Eastman catalog that was an airbrush-on, bake-it-yourself ceramic coating. It was pretty reasonable.
I shot the stuff inside and out. When my Mom upgraded to a ceramic-top kitchen stove, I saved the old [but still perfectly good] Hotpoint. Rigging a temporary 220 outlet in the backyard, I baked my Heddman 69230 Hedders at 500* F for 2 hours. [IIRC.] I think Black was the only available color then.
The Hedders came out pretty nice.

Then I made a fatal error and decided to put DEI header wrap all over the Hedders. I was unaware that doing so voided my Heddman warranty. Advantages were: an almost Cadillac-like hush to motor noise; lower underhood temps; and a NASCAR-cool look.
I assumed that shooting the coating on both inside and out, and that Arizona's notorious lack of humidity would allow the ''mummy-wrapped'' Hedders to function indefinitely.
I was mistaken.
Nature took 7 years to finally blow out my mummy-wrapped headers, but it did.
The hassle of putting on replacement #69230 headers was compounded by Heddman's use of the same P/N for fitment on a '68-'72 SBC in a K/1500 frame w/Manual [Z-bar/Clutch] on a new generation of header style with ball/socket collectors -- so my original 3-bolt flat 3'' gasket collectors had to be sawed off and ball sockets welded on by Midas guys at shop rates.

The new headers, I have not coated yet. I put them on with the factory paint to let it burn off.

On the L6 292 in my '68 C/10 Stepside, I put a set of Clifford ''Viper'' 3-into-2 headers in 1978. I painted them with VHT. They ran on that motor for 25 years. I rebuilt another 292 and was back on the road in 2005. My machinist hot tanked and bead blasted the Clifford headers. He said they were fine. I repainted them with VHT and they're still good and running on my current 292.

['68OrangeSunshine]

Here are shots of the blown-out hedders:

[YellowK5]

Header wrap is great for killing exhaust pipes...tempers the hell out of them

[MikeB]

Originally Posted by '68OrangeSunshine

On the L6 292 in my '68 C/10 Stepside, I put a set of Clifford ''Viper'' 3-into-2 headers in 1978. I painted them with VHT. They ran on that motor for 25 years. I rebuilt another 292 and was back on the road in 2005. My machinist hot tanked and bead blasted the Clifford headers. He said they were fine. I repainted them with VHT and they're still good and running on my current 292.

That's remarkable! Back in the 90s I sandblasted the original 2-inch rams horns and painted them with cast iron color VHT. The truck sat outside in the rain a snow most of the time, but that VHT held up well for 6-8 years or so. When they started showing hair line cracks, I replaced them with some Dormans, which for some reason I didn't paint.

Now I see where VHT Flameproof is a silica ceramic coating with a what I think is even a higher temperature spec than what I used. Apparently header tubes get a lot hotter than cast iron manifolds, but the the latest stuff might be worth a try.

[MikeB]

Got an e-mail from Jet Hot asking me some more questions. Here are the numbers from the latest quote:

H2L-1300P-Long 30-50" 2 Piece Header-Polish $433.40
UPS GROUND SHIPPING $101.20
INSURANCE $2000(Signature is Required Upon Delivery) $17.60
Payment terms Subtotal: $552.20
Total: $552.20 (USD)


On the plus side is their lifetime warranty, although I'd have to pay freight both ways.

[YellowK5]

Here the header installed. part #69640

[MikeB]

Man, that's close! What year is your truck?

I just remembered that back in the day my truck had Dart Iron Eagle heads when I installed the Hedman Elite headers. The exhaust ports on those heads were raised a little and the gasket surfaces projected 3/8" or so outwards. So the engine was essentially 3/4" wider than stock. In fact I even had to rework some brackets and change spacer sizes so the A/C compressor and alternator would clear the valve covers.

That said, I would have still needed to notch the driver's side frame rail with stock heads.

[YellowK5]

It is tight but noting hits!..the mufflers are a bit quite but it does have a nice rumble tone..Not bad for crate motor installed in 1988

[MikeB]

Got the Doug's 371Y. First thing I noticed was their name tag was welded on sloppily. Not a very good advertisement for their products! But to their credit, Hedman did send me a new driver side header.

In the meantime I did a test install on the passenger side header. While it does clear the frame rail, the collector is only a finger's width away from the TH350 trans, and it is aimed right at the crossmember, which means a sharp up or down pipe bend will be required. Hard to understand why it fits this way with so much room down there.

I'll install the new driver side just to see how it fits, and crawl under the truck to see how bad the passenger side is but I'm already leaning towards Hedman #62010 That PJ recommends. That way I get to control where the down pipe fits relative to the trans and crossmember.

I do have to say these Doug's headers have very nice port finishes, and the included gaskets fit both the headers and cylinder head ports very well. Gaskets are good quality, not cheesy paper like some. Flange bolts are just the right length and have a 3/8" hex head. Some you can get to with a socket, others with an open end wrench.

[xr4tic]

Do they hang below the frame at all?

Are you able to take any measurements? I'm looking for:
- Distance from center of flange to inside of frame rail (side to side measurement)
- End of flange to front cab mount bolt (fore/aft measurement)

I've got a Summit frame brace kit that I'll be installing this winter and want to make sure it will clear.

[MikeB]

Just noticed I said Hedman sent me a new header. Obviously I meant Pertronix/Doug's.

[MikeB]

Some more observations here after I crawled under the truck:

Take a look at the photos. Not only does the collector point right at the trans cross member, it's also inboard way too much, about 1" from the TH350. It needs to be around 1" lower and 2-3/4" to 3" outboard to take advantage of the pipe clearance GM engineered into the cross member (as shown above the old exhaust pipe).

Yes, I could use a tight S-bend, but that would affect flow, and it would hang down too low. Also, the collector would still be so close to the trans that I'd have to move it out of the way (sacrificing gaskets) to drop the trans, or even the converter cover.

As a buddy of mine said, "Huge fail." These are going back to Summit! Next up will be the Hedman 62010 stainless headers made in the USA. With them, I should be able to have a shop bend some down pipes to my spec.

[MikeB]

Using a $50 Summit Racing promo code, I just ordered the stainless Hedman headers #62010 like PJ has.

I'll connect them to the exhaust pipes using flex tube, and then have a muffler shop do it properly. Turns out there's one in the area that does mandrel bends.

['68OrangeSunshine]

Using the flex pipe saves you the noise and hassle of running open pipes.
I replaced some Headman headers a couple years ago. Even though I was carefull to order the exact same P/N, Headman ''improved'' their design, and the collector connection was changed from a flat 3'' - 3 Bolt/nut set up to a fancy Ball-and-Socket design, so I had to cut off the collector end at the exhaust pipes and drive 8 miles down to a Midas shop where their guys welded the fancy B/S ends on.
My 350 sounded like a taxiing B-25. I wore my flight line ''Ears''.
A city cop got on my tail for the last couple blocks, but he peeled off after I stopped and signalled a left into the muffler shop.
I tried the flex pipes on the 454 in my '67 Suburban K/10 full time, but they would burn out periodically, and I'd have to crawl under anmd replace them.

[MikeB]

When I was a kid, I drove my 57 Chevy with open headers to a muffler shop around 15 miles away. Did it early on a Saturday morning when traffic was light, but even under light throttle, I probably woke up everyone in my neighborhood!

[HalfBrit]

Originally Posted by MikeB

When I was a kid, I drove my 57 Chevy with open headers to a muffler shop around 15 miles away. Did it early on a Saturday morning when traffic was light, but even under light throttle, I probably woke up everyone in my neighborhood!

The struggle is real, lol. The first engine swap, in my '70 C10, involved driving (with open headers) 20 miles to work, then 30 miles to the exhaust shop. The looks on the highway were priceless
BTW, I apologize. In my earlier response I neglected to mention the aftermarket trans crossmember, that allowed me to use the 371Y, as opposed to your stock one.

[MikeB]

Originally Posted by HalfBrit

I apologize. In my earlier response I neglected to mention the aftermarket trans crossmember, that allowed me to use the 371Y, as opposed to your stock one.

Got info on that crossmember?

[LNP]

Originally Posted by pjmoreland

They also make them in other materials and coatings.

The 69020 are the same headers as the 62010 the only difference is they are not stainless steel. Those are the ones I'm gunna use. I'll just ceramic coat them.

[MikeB]

Originally Posted by LNP

The 69020 are the same headers as the 62010 the only difference is they are not stainless steel. Those are the ones I'm gunna use. I'll just ceramic coat them.

What will total cost be? And who will coat them?

[HalfBrit]

Originally Posted by MikeB

Got info on that crossmember?

Here's the link to the crossmember I'm using.
https://www.dirtydingo.com/shop/prod...oducts_id=1795