Header issue:

[elorenzof]

I have a newly built 383 stroker rectangle exhaust port SBC in a 1970 c10 4x2

I would of kept the rams horn exhaust manifolds however i was told that with a 383 the exhaust diameter of 2" off the manifold is not sufficient for breathability.

So I purchased Hedman mid length headers and installed. Right Side exhaust leak. ( I had aready taken it (towed) to a muffler shop to get the exhaust completed.)

I used the exhaust gaskets from the Felpro Engine gasket kit, i was told by a friend they are junk.

Three attempts to solve this header leak i FINALLY look at the header itself and the header is not welded correctly! The flange is at a "slant and there is almost no raised port around cylinder # 2 to mate against the cylinder head. They are dart 2 heads and i see no issues whatsoever with the cylinder head ports at all. So i got real expensive thick copper gaskets and tried again and its still leaking. So i went to Ramjet Speedway here in phoenix and purchased another set of headers. (this has been a two year build and i dont even know where my receipt is for the original headers i purchased.) The 2nd set of headers is just as bad or worse. Now the exhaust leak is WORSE.

How do i solve this? Does anyone have a suggestion for rectangle port mid length headers? I know i will have to re-dood my exhaust at the header junction but geez i just wanna drive this new truck.

At this time expensive headers sounds better than not driving the truck at all.

anyone?

[72c20customcamper]

Hard to believe that two sets of headers are defective . I used Hedman SS 62010 shorties on the 72 with a Blueprint 350 no issue . I would contact Hedman if you feel there’s a defect . Why did you use a different brand heard gasket ? The ones I purchased came with gasket and bolts .

I just purchased full tube Hooker SS for my 68 since I’m ordering a BP 383 for it . Was told the shorties do rob some hp as apposed to full length


Edit: well just read the fine print on Holleys site says they don’t fit raised port heads so I’ll be sending them back

[elorenzof]

I saw the Hedman SS 62010 - however the ports are oval (or round) and my exhaust ports are rectangle. Stupid question, can i use those? I was under the impression i HAD to use Rectangle port headers as my cylinder head ports are rectangle. (see pic) Also, the pic of these headers shows the mating part to the head as completely smooth. I'll upload a pic on Monday (The truck is at work) of mine and you'll see what i mean. Thank you for your response.

[72c20customcamper]

Originally Posted by elorenzof

I saw the Hedman SS 62010 - however the ports are oval (or round) and my exhaust ports are rectangle. Stupid question, can i use those? I was under the impression i HAD to use Rectangle port headers as my cylinder head ports are rectangle. (see pic) Also, the pic of these headers shows the mating part to the head as completely smooth. I'll upload a pic on Monday (The truck is at work) of mine and you'll see what i mean. Thank you for your response.

You don’t necessarily have to use round on round or square on square . Guys use factory ram horns on the blueprint round ports . I would think as long as the header and gasket make good contact with the head it should be fine .

I know the oring bead you’re talking about on the headers . If it’s missing on the one flange I would contact Hedman . They were great when I had a slight problem with a header bolt not going in . The dimple on the pipe wasn’t correct . They gave me a return number to have them sent back to Summit to exchange . But I managed to put a dimple in it with a piece of round bar and a hammer

[Cali72K20]

Here are a pair of lower cost options, both have 2.5" collectors.

https://www.roadstersupply.com/category-s/277.htm

I have a set from speedway motors and they rectangle ported.

[RichardJ]

Most header leaking problems I have seen were caused by over-tightening.

[jjzepplin]

I used Percy's multi layer aluminum and they seal awesome. Though it could be that I also file the header so that the entire flange is good and flat. I then cut the flange between the outer exhaust ports and the middle two.

[sloGMC]

i have long-tube hedman hedders on AFR heads, so i can't help you for mid-length hedders selection.

as for gaskets, after going through other manufacturers, I ended up with RemFlex compressed graphite gaskets and "stage 8" bolts with lock tabs. They are still leak-free after 4+ years and 14k miles, so I think they're doing well.

[OL SKOOL]

Go online Sanderson headers they claim no gaskets needed. I just purchased a set used but never ran mid length ceramic coated. I'm old and have had lots of different header combinations through the years. I'm really impressed with the thickness of the mounting flanges and perfect fit. I haven't ran it yet to see if they will leak. I would check everything over real good with what you have. I have to agree with the other gentleman that 2 sets of headers would leak is strange. Good luck i know aggravating looks like a beautiful truck.

[jjzepplin]

I used to live in Oakland California and I put high performance engines in cars and trucks. When we ran into an issue where headers were not made for the application, we took the cars to Sanderson's and they would fab up a pair. They say you don't need gaskets but that is only if your heads are perfect and you won't drive it much. They do some fine work though, at least they did.

[72c20customcamper]

Sanderson recommends a thin bead of Permatex black high temp silicone around the bead . I am looking at these CC10BP-158 made for Blue Print heads . Only thing I don’t like is they aren’t available in stainless steel.

[68isgreat]

Originally Posted by 72c20customcamper

Sanderson recommends a thin bead of Permatex black high temp silicone around the bead . I am looking at these CC10BP-158 made for Blue Print heads . Only thing I don’t like is they aren’t available in stainless steel.

I didn't know you could put silicone on exhaust in general. I would imagine you could try this on any kind of manifold or header. Good to know!