If you want to be sure that your manifold won't crack, chamfer the pipes that are gonna be welded to the flange. Because even if you weld very hot, TIG is not the champion in penetration. The welds can seems damn good but have no penetration. Where I work, from 3/16 and past, we chamfer every pieces that we weld.

when tig welding 304ss to mild steel, it is best to use 309L filler. i also weld the inside of the joint as well as the outside on all flange to pipe joints (head, turbo and wg).

schedule 40 is too heavy imo, i use schedule 10 for manifolds, plus they are cheaper.

as far as warping goes, even when bolted down, you are going to get some mild warp in the head flange, it is pretty much unavoidable. but if you heat cycle the manifold a couple times on the car and re-tighten the head studs in the proper sequence while it is still hot, it will flatten out. i've done this with 1/2" flanges that were warped 1/8" and by the end of the summer it was glass flat.

I just received 2 BP flanges from Mr. Weirtech. Very nice pieces. Better quality than the ETD flange and MUCH cheaper. I haven't started welding to it yet but there should be no problems.

I have used sch. 40 1.5" weld ells from mcmcaster (I can pick them up will-call so no shipping) on all my manifolds mostly because the ID matches the port size almost exactly. Plus it makes a nice solid manifold and I've never had any cracking issues; I don't saw in between primaries on the head flange.

I have never tried schedule 10, but maybe on one of my next manifolds I will. The larger ID shouldn't hurt. It would take less time to build, that's for sure.

Nice looking manifold Wier.

This is all good to hear, I am glad you proffesionals are joining in to advise.
Dark dude, chamfer means to grind down at an angle the ends of the pipes where they meet, right? Kind of like weldels come when you buy them...? I assume that is it.

Aaron, only reason i wanted sch40 is because that's what my friend used and that mani is bulletproof. If you really feel that sch10 is sufficient enough and that i should not worry about it cracking with a bottom mount turbo, then that's what I will use as I do trust your judgement. Right now is the time I need as much input as i can get as D-Day is approaching.

Tim, I found that 1.5" weldels from Acestainless are really 1.610" ID or something close to that, is this the case with the McMaster ones as well? Or is this maybe the norm?

i think most if not all of the ace stainless stuff is schedule 10... i am going to see if i can get a good source for elbows locally and start offering them, although i don't think i'll be able to sell them as cheap as ace.

if you are more comfortable with schedule 40, go for it. i've repaired a ramhorn manifold that was made with 10... i won't mention company names though, but i've never had problems with my own. i haven't had any manifolds crack where i used schedule 10, although i did have a wg pipe coming off the collector crack at the joint because i used a different stainless tube instead of the matching sched10 stuff.

imo, for short runner manifolds it isn't going to make much of a difference in the material that you use... it is more with the bigger and longer runner manifolds when weight comes into play and vibration due to lack of proper bracing is when you start to see cracks.

My runners will not be nearly as long as the ones in the mani you are building, my only concern was because I will have a bottom mount, I don't know if that will make a difference or not.

Ace has sch40, in the 1.5" diameter.

If you're really worried about it, you can make a quick and dirty adjustable heim support (or cheap nonadjustable) to keep some of the weight off. I would make a plate that bolted through 3 valvecover bolt holes so you don't strain just one and run the heim to that plate. Parts from mcmaster for the heim adjustment would be cheap. I think they're around $10 a piece there maybe more like $7 if i can find the part number.

Good to know that compatibility isn't an issue, and thanks for the tip on filler rod. Looks like stainless els and mild flanges FTW.

Yep Zabaz it's that!

Yeah I was going to do that, for better penetration just wasn't sure that's waht you meant.
I can't effin wait to start the damn thing.

Just ordered my flanges from weirtech. Good prices and good price on shipping!

Parts shipped two hours later with tracking info! Customer service at it's best!

thats my car :)

maybe i'll ditch the etd for that manifold, looks great

yeah, marlon, your dp is done, i'm just doing the wg/dumptube. sorry for taking some time to do the mock up... surprisingly it didn't take me all that long to do. the wg is going to be tight in the new location, but it will fit. i can't remember if you wanted me to do that charge piping section or not. i remember talking about it, but couldn't remember if it was something you wanted done now, or after you got it back on the road. lmk, aaron.

pm sent
in a couple of weeks ill killing my friends sti :)

It would be sweet to just be able to buy a manifold made from weld els for a 1.6 that looks like a BEGI S4 and allows the use of a T25 or one of its many variants with a Nissan RWD SR20 turbine outlet pipe, which is commercially available for dirt cheap. And with a compressor inlet position that lets the power steering and A/C stay in place. Mr. Wier?

Two more manifold questions:

Are fittings available to weld in the manifold for the EGR tube fitting? IIRC, the 94-97 was a male thread on the mani and the 99 is a female, otherwise I would hack one off of a 94-97 stock mani.

Second, can someone give me a general dimension for a flange-to-flange distance and centerline of exhaust port to centerline of turbo flange port for a BEGI/FM cast manifold? Because I have a BEGI downpipe, I'd like to best replicate these dimensions to help ensure everything will bolt up without having to mod the downpipe.

10+k and still goin strong.

http://www.aemfic.com/images/turbo/mani1.jpg

http://www.aemfic.com/images/turbo/manifold1.jpg

http://www.aemfic.com/images/turbo/manifold2.jpg

http://www.aemfic.com/images/turbo/turbomounted.jpg

Stein, can't tell you distance, but the best way to do it, if you have to, is to mount your turbo to DP and secure it in place (like let it hang off of something, like a stick maybe) and then build the mani up to that

Yeah, I considered that, but took the car out of service. Not a biggie, because it is a third car, but it would have been nice to build everything in advance and go from there. Once the turbo arrives, along with the flanges, I'll take a look at everything.