Where do Ebay mani's crack?

[joegamma1]

OK, I have an ebay exhaust mani, it looks good but we all know it'll crack probably sooner than later.
BUT, I can brace the crap out of it, I can tig it at work if someone can tell me where they've seen em crack.
I do not want guesses!
If you've seen one crack or cracked let me know where it cracked, I've already come up with some ideas but i want some input from those of you with first hand experience either owning one or seeing the aftermath of someone elses.

 

[KazooGS-T]

I've seen them crack both on the flange to the head and on the runners themselves.

The cracking from the runners is probably due to weight on the manifold. So brace underneath the manifold where the turbo flange is and brace the runners on the head flange.

Also, occasionally the welds themselves will crack.

 

[joegamma1]

Hope its not a lost cause.
I have plans to brace from the head flange to the turbo flange as well as each induvidual runner at the head(although there's already a small piece welded to the top of each one).
I can take it back to work if it does crack at the welds, but i dont want to have to do it every week.

 

[willydsm]

If you are worried about an ebay manifold then dont get one, IMO i wouldn't get one from ebay. save the extra money and get one from a reputable shop.

 

[Doubleot]

If I was you I'd just try and sell it. Its really not worth the hassel of having to take it off and weld again month after month. Just my .02cents
Port your stock one and it will make your turbo spool a little better.

 

[jjrock5]

Get yourself a FP mani and call it a day.

 

[99gst_racer]

My roommate rocked an eBay manifold and 16G for 3000 miles last year with no issues. It may be of lesser quality, but they won't all fail.

I agree that the FP manifold would be a much better option, but that suggestion also doesn't answer any questions.

Tubular manifold are most suceptible to crack where two pieces meet at 90* and where that joint supports weight. IE: around the runners at the head flange and around the turbo flange near the collector. But that's also not to say that it cannot crack anywhere. Just brace it from flange to flange on the underside and hope for the best.

 

[JusMX141]

A Pacesetter tubular manifold on my buddy's 2G lasted 8 months and right around 3k before the #4 runner completely broke away from the collector. No warranty repair or replacement by Pacesetter, so that was over $200 down the drain.

Replaced the Pacesetter with a tubular eBay header (DNP knockoff) when the 16G was upgraded to a 20G. I remember that we needed to grind one of the manifold studs VERY short in order to get the #3 runner to clear. This header offered better access to the two rear bolts than the Pacesetter, but ths header also cracked after about 8 months and around the same mileage as the Pacesetter. This time the crack was around the front of the turbo flange instead of where the runners meet the collector.

In the end he wound up with a ported Evo III cast manifold, which is crack-free and still on the car to this day.

 

[Bender]

Just redo all the welds. You will then have a Punishment Racing "budget manifold".

 

[joegamma1]

If you are worried about an ebay manifold then dont get one, IMO i wouldn't get one from ebay. save the extra money and get one from a reputable shop.

Good idea, please reread the first 7 words in my initial post.

Doubleot; I just dont feel comfortable selling a part that we all know isnt going to work in present form. I would feel like I'd be screwing someone over, so I'd rather at least try to make it work for myself and who knows I may discover the key to making this type of el cheapo mani usable for others, in the process. I dont have much in it, so if it turns out that it fails than it's ok, at least I'll have the experience to pass on to others.

My intentions were to use the stock mani, but after taking off the heat shield and discovering two cracks that look like they are going to continue to crack the 3 inches to meet, I figured i'd try this, but I'll probably just end up buying another stocker in the classifieds.

jjrock5; doesnt really answer my question, but thanks.

Just redo all the welds. You will then have a Punishment Racing "budget manifold".

Thank you, I did consider that, I'll ask another welder what he thinks, Although it has been my experience that the actual welds dont break(except for impurities in the metal or improper technique) but the metal right next to a weld is slightly weakend when heated for the welding. But the welds do look like have good penitration so it my not be wise to re-heat the metal again.

 

[tkelly27]

I say try it. You don't really have much to loose. I have a pacesetter sitting in my garage. I could never get it to seal up properly to run it long enough. Still has most of the paint on it.

If you have a brace supporting the weight of the turbo the only real loads should be thermal, which shouldn't crack a weld of similar metals.

OH! A big one people forget, support the down pipe and make sure you have a flex section. You can get away with it on a cast manifold, but that's a huge moment arm hanging off your turbo. The down pipe should be able to support the turbo by itself when it is attached to the block with the flex section there to take up engine torsion.

 

[joegamma1]

OH! A big one people forget, support the down pipe and make sure you have a flex section. You can get away with it on a cast manifold, but that's a huge moment arm hanging off your turbo. The down pipe should be able to support the turbo by itself when it is attached to the block with the flex section there to take up engine torsion.

That is true, i am installing a 3" down pipe and was thinking of doing away with the factory dp bracket just below the turbo, but i think I'll keep it and adapt it to fit the 3". Thanks for reminding me.

 

[joegamma1]

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OK, this is what I came up with. It may not show in the pics but i also braced the top of the runners to the head flange with 3/4" square pieces just like the bottom was originally.
My welder also found 3 pinholes that would have been a real b!t(h to find after the mani was heated a few times.