bert4332

Definitely share your fix to the 525 header problem!!!

TWIN-SPINS

the newer style does not,,,does not ,,,have the outer tube welder to the flange,,

PARADOX

I don't have a "fix", just some things that will help based on discussions with a lot of people, and companies.
I will elaborate on this later, but to reduce problems at the 1/4" gap, have a good welder weld some beads between the flange and the other tube. 6-8 at each gap/tube. Basically you will thicken the "inner" tube. Less movement, less cracks, more mass, better heat distribution.
This will add "mass" to that area and make it stiffer/stronger.
Just need to be careful don't burn through the tube.
In short the idea is to connect the other tube to the flange also.
Connect the top of the headers with a bar at top of the header. Like a tie rod. This will reduce vibrations and side to side movement. The weakest point is at the smallest area and thinnest. THE GAP.

Dave M

That's what I thought. But Paradox said that CMI says that the 1/4" gap is the problem. Wouldn't that would mean that the "newer" sytle is prone to cracks too?

Well, it is what it is......I will just keep a real close eye on mine and hope for the best.

PARADOX

Dave
Read it again. Newer style is NOT WELDED TO FLANGE = 1/4" +- gap.
I did not referenced what CMI said. Others did. CMI did NOT SAY they have ANY problems.

Dave M

OK, got it, newer = 1/4" gap.

The procedure you described includes adding material to the area of the gap. The GAP is the weak point

So, the newer style is prone to cracking issues too.

JMPH

is this related mostly to the 525's

Baja_man

Mainly 525....more so with staggard 525's....but NOT limited too just those.

PARADOX

Noooo... Not limited.. Don't know where did you get this or why you even commenting when you don't know.
Many CMI headers have problems. 496's, 500's ,525's, 600, 700. and even others. 525's are one of the most sold. Thus, most referenced.

bob_t

I thought this "gap" is what CMI called their "cool collar" design that was supposed to be the best thing since sliced bread in the world of water cooled marine tube headers ... rendering those designs without it inferior and obsolete? The direct welded tubes like the old E-Top style are better, now? Are the one's with the "gap" cracking predominantly interally or externally at that junction from one tube to two tubes? I guess I'm confused now.