Middle of a 12v compound build
 

So I am building a cheap set of compounds, hx35 over s475 I have the hot pipe holding the two together and on the manifold. Starting the intermediate pipe, going with 3 or 3.5 but I'm wondering for the guys who built their own, what was the radius for the 180 bend? Or does someone know a way to measure what I need? I'm thinking measure from the center of the 35 intake to the center line of the outlet of the 475 (in a parallel line) does that sound right? Just don't wanna order a mandrel 180 that when hooked to the 35 is touching the fender lol thanks!

When I built mine, I used 4" piping that had a 4" CLR. The pipe was 12" overall width on the 180 bend. They were mandrel bent 90's I got from a muffler shop.

Ok so if I'm thinking right, from the center line to center line of your 180, would be 8 inches? I measured from the center of my hx to the center of where it needs to be on the 475 and it was right around 5 inches. Of course different hot pipes will put the 475 in different spots requiring different radius.

What are you running for chargers? This is my first set of compounds and from what I see, 4 inch seems to be a little large unless running something with higher hp, and like a 66 over 480 or a 400 over 500 type deal. But I have no idea

I guess I was seeing, to keep all your piping the same size, so being the is pipes are 3, to stay with 3 on the intermediate.

I was running a GT3782R over a GT4202R. 4" is definitely larger than required, but 4" inlet and a 3.5" outlet made it easy with only one transition boot. And aesthetically (to me), 4" looks better.

With the ball bearing turbos, they also have water lines coming out the side of the CHRA. The interstage pipe had about 1/2" clearance to the water line coming out of the top charger. I posted pictures in the 'lets see your twins' pictures that is in the staging lanes, I believe.

the discharge on your primary is 3.5" so I would use 3.5" piping between primary and secondary. you are correct in assuming that 4" would not be necessary until much higher power levels.

Ok yes I wasn't sure what my discharge was going to be on the 475, I figured 3.5 because 3 inch slips right inside the flange. Haven't decided if I want to run a v band flange on my pipe with no boots down there or cut the flange off and weld on a straight with bump, in which I could do 3,3.5, or 4.

For anyone wondering about finding the measurements of a 180, I've learned that most 180s are sold by center line radius, which is from the beginning of the bend to the middle of the bend, to figure out how wide the whole unit is going to be, you double the center line radius. So most 3 inch 180s are 4.5 clr, which makes the 180 9 inches from the center of one leg to the center of the other leg.

You can get a v-band flange to a 3.5" slip joint to run a boot. Saves a bit of fabbing, especially if you can't weld aluminum. You could weld the flange solid to the interstage pipe, but then alignment becomes much more of an issue. I've had my twins at over 100 psi, and the primary would usually be about half of that, and boots on both ends never gave me any issue.

I used all 3.5" on mine and welded an o-ringed v-band flange to my S475 outlet. It's not necessary but it does look nice and it's one less boot to deal with. 3.5" also works great to squash and fit in a T6 flange. More than one way to skin a cat on compounds for sure...

Hotpipe is done, however I'm still on the intermediate. Well actually I'm on vacation in Hawaii, but thinking about what I have to do when I get home lol. For anyone with compounds could I get you to measure something for me? Gman99, you have I think the set up I want to do with the flange welded to the pipe. The measurement I'm after is from the center of one leg to the center of the other leg on the "U" bend. The one I'm looking at buying is a 5.5 clr, which would make it a 11 inch center to center on the legs, which seems a bit big but I'm 4k miles away from my trucks so I can't measure :( hoping to order the crap so it's there when I get home! Thanks in advance!

And I'm doing 3.5" pipe as well

My pipe is 3.5". Two 90's with 3.5" clr. Makes center to center on the u bend 7"


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Yep, same specs I used.

http://i1292.photobucket.com/albums/...pswn4mrswh.jpg

Gman99, thanks for the pic, looks like you used a 180, not 2 90s, but assuming you did a 3.5 pipe with a 3.5clr on the 180? Just got back from Hawaii and had to pull a Nv4500 swap kit I sold, time to get back into these compounds though! Thanks!