Turboing when a manifold isn't available?

Just wondering peoples opinions as to what the best solution to my problem might be.

I'm working towards turbocharging my Mazda b2600 engine, but despite my best efforts, there doesn't appear to be a turbo manifold available that will fit.

My first thought after reading the ls breaking point thread the other day was to just use the stock exhaust manifold with a j pipe or similar, seemed that a slightly remote turbo was no real enemy to power and given that I'm not trying to chase massive figures would probably work out OK.

Next was possibly chop and modify the existing manifold, but being cast iron, that doesn't seem like it will be all that Feasible?

Alternatively, I've thought about trying to find an eBay manifold with similar runner size and spacing and looping off the flange and making a new flange to suit the b2600 head.

Last option would be to just bite the bullet and fab up a log manifold from scratch...

Anyway, that's my thoughts, what says the hive?

We chopped and welded a stock cast manifold on a Toyota V6 T100 years ago to install a T3 turbo. Yes, that's all singular - the other side was left alone. Stock clutch, rising rate fuel pressure regulator, 91 octane fuel. There are so many reasons why it was a bad idea, but we used the truck as a tow vehicle for years. Never did have a mechanical problem, although it should have. I've been impressed with Toyota trucks ever since.

Anyhow, I guess my point is - do you have a spare engine? If I did it now, I'd probably weld up my own log manifold from scratch.

J pipe or order/salvage a flange off your manifold and use weld els to make whatever manifold you want. Which depends on you and where you think is best to put the turbo.

I have thought about buying a cheap header, cutting the collectoroff, and wwelding a turbo flange on. Dunno if that would work though.

Just go to the junk yard and grab a spare. Can either hack that up or design your own based on that.

wait didnt the B2600 have a Mitsubishi engine? the same engine in the Mitsubishi Starion which came with a turbo. I may be wrong though lol

Somebody post up a picture of the manifold on the Texas A&M Miata from the Challenge. It was welded up from schedule 40 weld elbows and tees with a water jet cut flange. A really pretty welding job it was.

In reply to Keith Tanner:

Well that's some very anecdotally good evidence that maybe butchering a stock manifold isn't the worst idea.

By spare do you mean manifold or engine?

In reply to chiodos:

Well a j pipe will put the turbo into a good position pretty easily, being rhd I don't have a brake booster or steering column to contend with. If I was going to the extent of weld elbows then I'll just make a log Mani from scratch.

In reply to Dusterbd13:

Same thought crossed my mind, but the only headers I can get have pretty long runners and would require a lot of work to the point that from scratch fab would be almost the same amount of work. But something I'll look into further, especially if I can get some cheap used headers.

In reply to clutchsmoke:

From what Keith said, that's actually starting to look like an attractive idea. The stock manifold has a pretty good open collector which would probably be sufficient for what I'm doing.

In reply to echoechoecho:

Unfortunately no, the early ones did, but then Mazda made their own and aside from the displacement and presence of balance shafts, they share very little between them.

Just do the exact opposite of this.

The guys on fordsix tend to all use a j pipe. If i wanted to keep my i6 thats the easy button.

Knurled wrote: Just do the exact opposite of this.

I was going to comment how ugly that is, but you know what? BOOOOST! So it doesn't matter

expensive but maybe an option?

This might help:

http://www.jgstools.com/turbo/index2.html

If they don't have an exhaust flange to fit your motor, just order the universal kit and make your own flange from a header or have one cut from an exhaust gasket.

Another option: ditch the Mazda G6 2.6L for a F2T and summon the dark arts of the F2T mafia

https://classicmotorsports.com/forum/grm/what-if-i-wanted-a-cheap-stupid-fast-truck/89919/page1/

If you end up welding the cast manifold, my best luck has been by preheating the cast part(throw it on a charcoal grill or over a fire pit), then burning it in as HOT as you can, then cover it in a welding blanket and/or in a large bucket full of sand and cover with more sand. Then sit overnight.

In reply to Knurled:

Oh cmon man, that's beautiful....

In reply to MrJoshua:

I wish it was that simple, that'll be the early Mitsubishi manifold.

In reply to Stefan (Not Bruce):

Thanks for that, I'll contact them and see what options are available to me. Though including shipping and exchange rate it may be easier to just buy some weld fittings and get some flanges cut.

And yeah, an f2t isn't out of the question, I already have an f2t turbo manifold at home and the truck is currently running an fe....

In reply to flatlander937:

Thanks, that's some good advice, I'm guessing that's basically a home version of degassing yeah?

Welding cast?

Stick welder with high nickel rod.

Preheat part, like really hot.

Put the part in sand afterwards with no exposure to air so it cools slowly.

http://www.lincolnelectric.com/en-us/support/welding-how-to/Pages/welding-cast-iron-detail.aspx

I'll see if I can dig up pictures of our particular butchery. The truck did survive in part because it was driven with mechanical empathy. But yeah, welding cast involves a lot of careful heating and cooling to avoid cracking. Last time I did it, we used a torch instead of a MIG to do the welding IIRC.