The solid mild 1/2" flange on my last header warped pretty bad.

 

during welding or after the fact?

 

Yep...you know what you're talking about. I didn't mention that a lot of those manifolds are cast, and they neither have the same material (cast vs. stainless), nor do they have the additional distance to the collector, that your pipes do. So, yours won't be susceptible to cracking like the cast ones. I have seen split flanges on headers (mine's one example), but as you've shown, it isn't a necessity.

I like the cooling block idea. I'm going to adopt that for my weld setups. Thanks for the links.

Did you ever read that document called Maximum Boost? You might find it interesting. I think the guy who wrote it was a designer for F1 cars.

Oh, have you considered a spool valve for that puppy of yours? I ran across another thread where a guy installed one, and me being a newbie to the turbo gas engine world, I thought it seemed a great idea. Your thoughts?

Excellent thread you've provided. Thank you very much for your time and input!

John

 

after the fact. It was fine for a while at a low power level, but when I cranked up the juice that's when I have problems. Lot of extra heat when running really high power. Cast isn't necessarily bad, the reason most mild headers fail is because of the welds not really the material. A casting is much stronger by nature because of the lack of welds..

 

Thats really odd. I've never had a 1/2" flange warp after the fact.

From what I've seen mild cracking has more to do with the fact that it isn't properly stress relieved after welding and overall material break down.

Heat cycling will kill any material and I've seen mild go to crap pretty quick. The heat, carbon and combustion emissions do a number on anything. You'll also accelerate that process tremendously by using header wrap. i know a lot of guys use it to keep heat in and increase spool. It does a number on tubular headers for sure.

I'm sure that comment will start a **** storm lol

 

I read maximum boost a long time ago. It's ok to get started, but it shouldn't be taken as gospel. A lot has changed in the last 10 years that contradict some of what he writes about.

It's funny you ask about the spool valves. I saw another member made his own and I had another member ask me about it a few days ago. They can work great, but can be very finiky, similar to the extronic exhaust cut outs. Great idea in theory, but sometimes can have issues in practice.

Here's my take on quick spool valves:

If you're going to buy a quick spool valve, sound performance are the guys to buy it from. They did extensive research with those valves and use exotic materials for the mechanical components.

Originally when those valves came out there were handful of guys trying to make them work, but SP were the only guys to make them work reliably on gas motors. They were initially developed for diesel engines, which you can get away with less quality parts due to diesel burning so clean. Gas engines carbon emissions get gunky which can make the valves stick. You won't figure this out until later on after you use it. There was also the problem with leaking through the shaft seals.

I've never personally run one, but my buddies have with success. you can't run them on divided manifolds which is why i've never tried one. Almost all of the manifolds/setups i've done since they've been out have been divided or the turbos are already small enough to where they get quick spool and don't need it.

I'd say give it a try if you're worried about spool. Remember that they add an 3/4" worth of spacing and there is a large actuator that you have to have room for. The other member that PM'd me about this wants to use it on a BW box unit which comes with a 92mm 1.32 a/r divided back side. Those turbos are pretty cheap and work good, so having the valve on there to compensate for such a big hot side makes sense. I'm interested to see what it does, but i imagine it will help out a lot.

It is also another system that you need to maintain. I typically try to keep things as simple as possible for the goal at hand. In most cases, i wouldn't size a turbo big enough to need one. You'd want to set the turbo as small as possible to attain the goal you're going for.

I also hear "room to grow" grow quite a bit. I would venture that most don't ever grow past initial thoughts and by the time you do, if you do, spending another $1500 on a bigger turbo isn't the end of the world. Most guys are putting 75mm+ turbos on their trucks/cars which will easily support 800~1000whp. In order to support that kind of power you're spending a ton of cash on everything else, so the extra money to get the right turbine wheel & housing shouldn't matter. realistically, most won't make that much power let alone want to upgrade to something that would support it.

I'm thinking I want less power. My initial goal was for 1000whp, but I think I'd be very happy with 700whp. I might go with a smaller turbo in the future.

 

Mine has warped before. I had the log manifold flange on my old kit milled twice.

 

I will say that out of any configuration, logs are prone to cracks. That's interesting you guys are seeing warpage after the fact.

 

I think me and jake pushed more power through them than most. More power means a lot more heat.

 

or bad tune lol..... j/k

There could be a lot of reasons why they warp. It's pretty intense that a 1/2" steel flange on a head that is 200ish can warp while being securely fastened.