New manifold build, comments?
 

hello
i am making a new manifold and below are some pictures of the fabrication. i am open for suggestions and comments what do you all think of this.

http://img257.imageshack.us/img257/7...0115wq2.th.jpg
http://img257.imageshack.us/img257/1...0117qr3.th.jpg
http://img257.imageshack.us/img257/5...0119vd8.th.jpg
http://img257.imageshack.us/img257/9572/img00116yv6.jpg
By musanovic, shot with BlackBerry 8100 Series at 2008-02-24

by the way it is not done yet. sent it to the shop to get tig welded before putting on the collector for External wastegate.

The main suggestion was going to be get it tig welded, good that you're getting that done. You also have a pretty large gap between runner 4 and the flange outside of that it should flow pretty well. What about turbo placement, are you going to cut the collector so that it angles the turbo or do you plan to make it a vertical top mount?

turbo is going to be top mounted and is going to be angled towards the engine. the collector is going to take car of the angling part. i want to put the wastegate on the collector so it will vent all the gases from all 4 runners. the gap on runner 4 is going to be fixed during welding. it's not easy to make everything fit as it seams. glad you like it.

the collector looks pretty fugly.....but it also looks like 2-3x better than either of your over the counter options. Should do really well.

collector is not on yet it is going to be put on after the initial welding is done.

I always wanted to know: All people that makes their own manifold, do they bend the beginning of the tubes that are welded to the flange so it makes an oval hole like the flange or do they just weld the tubes round as they are? And what is the dia and sch of the tubes?

Thanks

I like. Where in NC are you?

Greensboro

i made my tubes oval with the vise that you see the manifold on. its tough but after a little heating it goes easy. diameter on the inside is 1.6 inch. and it is schedule 40 stainless steel.

Nice work man. Where did you get the flange, or did you make your own?

I was going to ask that as well. Why does it have the 2 large extra holes?

most likely to allow for thermal expansion.

That's what I was assuming, though it would be better to do that across the entire manifold and two or three cuts between the runners with the band saw would accomplish that as good or better than the holes.

don't forget the external wastegate port - now's the time :bigtu:

It seems like 2 and 3 is longer than 1 and 4, you might want to consider making them equal lenght, seems pretty easy.
Have you done any pulse calculations or is it placement and space that mandates its size?

its ver difficult to make a top mount equal length while retainging AC and PS, there is not much room there to do as you please
so IOW space is the mandate then, yeah...
this looks very much like what i have in mind, just upside down...

the external wastegate port will be on the actuall collector that will get welded on after the pipes have all been welded together
he did tell me that once its all TIGd he wants to trim down the ends of runners 1&4 to make it more level and then the collector comes on

overall i think its a very good design and it should work very well, great turbo and WG placement (and good room for DP routing-quoting musanovic here)
great work

it is a stock flange of a stock header

just like whaamx5 said room is the worst enemy. i just don't like the trade off of not having PS and AC. if it was a track car it would be all different but i do enjoy the cold air. lol.

Looks great. Horray for DIY. good job. I wouldn't worry about equal length, not worth the grief. Pulse calculations? hmmmmmmmmmmm

I personally also make the tubes oval at the head flange, but others don't, and there are flanges out there (JGS, Lovefab???) that are machined oval-to-round with c'bores to make it easier & smoother to do round pipes.

i was able to make the pipes fit together a little better when i made them oval. airflow seams really good at the flange when pipes are oval compared to round. if you can do it why not. right?

ps. what are pulse calculations? i have no ideal how to do them if they exist.