what turbo headers for a 318?

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Caco2120

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So im contemplating a mild twin turbo setup on my scamp. Cheap ebay t3/4 hybrids. My motor is a 74 318 that I imagine is all of 8.5 to 1 compression. I plan on using a fitech or sniper from pace, and only running 7 or 8 psi. I imagine the teen will live just fine as long as its not wrung out or pushed beyond that. And heaven forbid she goes....not like its a virgin 340...

But I digress. something I see almost no offerings on is turbo headers. I know mopars can switch left to right, but dont seem they can flip vertically.

I see magnum truck shorties, and I see sbc turbo headers. I imagine cutting off the sbc flange, and re welding a mopar flange is probably just as Easy as having to take a magnum header that is pointing downward and weld on a t3 flange and figure out how to point them upward...anyways. thoughts on the lesser of evils header wise?
 
Does the car have power steering?
Currently. But im under the assumption the box and pump need to go. another ebay option...how good or bad are the reman $250 Manual boxes. Lol a $600 flaming river ain't happening.
 
These.

tmp_3593-Screenshot_2016-10-14-19-43-141631773945.png
 
Im thinking the sbc headers are probably the most realistic. I have a set of sbm junk headers I can steal flanges from. Thoughts?
The block headers I think would have no clearance, unless flanges were cut and swapped to flip vertical.

The mags would point down if flipped...maybe they would work for a single gt45 and a merge pipe...but I really dont want a single
 
My set up was built using the headman block huggers and the just made a pipe off the flange on the header, runs between the mount and block and up to turbo. In this section go to page 6 and look at mad dart build. I bought the car off him but you can see how he built the set up aka my set up.
 
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My set up was built using the headman block huggers and the just made a pipe off the flange on the header, runs between the mount and block and up to turbo. In this section go to page 6 and look at mad dart build. I bought the car off him but you can see how he built the set up aka my set up.
thanks!
I started going through the 70 page build thread... and for some reason the pics are all click links. I wish they just displayed.

So you have block hugger center dumps, and essentially they just route forward via normal exhaust pipe, but u have a gt45 flange mounted to the ends? I dont have a tubing bender. So if I can just swap flanges, I think I can take the bulk of the hot side fabrication out of the equation. Then I can bolt on a simple t3/4 90 degree downpipe, and have enough exhaust on it to at least get it on a trailer to have a shop do the turbo back. thats my thoughts anyways? how much bracing do you need to support the weight of the turbo? Brackets off the block?
 
You can buy the bends and cut and weld, and yes the flange was welded to the pipe, he made some braces off the heads to support the turbo. 02 sensor after turbo, atleast I think 12inches away from the outlet. You can always try the swap of the flanges, or swap the rear exit headers and have some elbowsort made or percision turbo might make one with the flange, you can always brace off the frame engine anywhere you like, if you look into the elbow it would just need a vent band flange welded the to header to connect to the eblow, something like this

$_1.JPG
 
Im thinking the sbc headers are probably the most realistic. I have a set of sbm junk headers I can steal flanges from. Thoughts?
The block headers I think would have no clearance, unless flanges were cut and swapped to flip vertical.

The mags would point down if flipped...maybe they would work for a single gt45 and a merge pipe...but I really dont want a single
I like your idea of the SBC headers. Is the port spacing the same as SBM? It would definitely give you more options. The Dakota headers will not fit the passenger side when reversed. One of the tubes will hit the fender well. Drivers side should clear with manual steering.

Best of luck with your project.
 
You can buy the bends and cut and weld, and yes the flange was welded to the pipe, he made some braces off the heads to support the turbo. 02 sensor after turbo, atleast I think 12inches away from the outlet. You can always try the swap of the flanges, or swap the rear exit headers and have some elbowsort made or percision turbo might make one with the flange, you can always brace off the frame engine anywhere you like, if you look into the elbow it would just need a vent band flange welded the to header to connect to the eblow, something like this

View attachment 1714980149

Thats for an external wastegate correct? most of the little hybrids have integrated wastegate. but I get youŕ point.
 
I like your idea of the SBC headers. Is the port spacing the same as SBM? It would definitely give you more options. The Dakota headers will not fit the passenger side when reversed. One of the tubes will hit the fender well. Drivers side should clear with manual steering.

Best of luck with your project.

Yes, I have found several people that have swapped flanges from sbc to sbm on other builds. usually hot rod guys that bought swap meet headers. so they must be close enough. I think this is the simplest route.
this is going to be a fun project! never turbo'd anything before as blow through carbs were always a mystery to me. but with the fitech or sniper..."how hard can it be" lol. I figure it makes enough sense to try. since they come on softer...the 904, 8.25, and oe converter aren't an instant concern like if I was just building a 450 hp engine. 8 psi shouldn't kill something with low factory compression....famous last words anyways :) lol
 
Check out my build. Single GT45, E85 and the Fitech unit, mostly stock 5.9.
I think you can avoid some hotside fabrication headaches going with twins, but it will present challenges on the downpipe side. You could go super simple and just dump the downpipes in the fenderwells.
 
Check out my build. Single GT45, E85 and the Fitech unit, mostly stock 5.9.
I think you can avoid some hotside fabrication headaches going with twins, but it will present challenges on the downpipe side. You could go super simple and just dump the downpipes in the fenderwells.

That was my thoughts on small twins also. Two into one intercooler simplifies even more fab on that side at least also.

I figure worst case on the hot side, I can run them under the k, and pretty much be a traditional "header back" once you get past the firewall. I have a buddy with monster 2.125 tubes with a sb. one tube through the fender. I imagine if those fit I can fit a single 2.5 downpipe somewhere out the rear.

Only goofy thing I see with the sbc headers is they appear to point the turbo east/east opposed to north/south. So a cone filter would point inward/outward. Opposed to forward. If im looking at it right.
 
Check out my build. Single GT45, E85 and the Fitech unit, mostly stock 5.9.
I think you can avoid some hotside fabrication headaches going with twins, but it will present challenges on the downpipe side. You could go super simple and just dump the downpipes in the fenderwells.

I checked your build out thanks. which ebay bov are you using?
 
If possible get a godspeed one, those are what I have as well and mad dart tested them and they help psi awesome
 
Mostly just sound, on blow off. You can YouTube blow off and see which sound you like better. I had a hks race ssqv on my built srt4 and loved the sound of it. The first one look like a greddy piece but is a knock off. Just don't recirculate it sounds better to atmosphere. My current build has twin tial looking ones but I believe are godspeed as well.

50mm-bov.jpg
 
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Mostly just sound, on blow off. You can YouTube blow off and see which sound you like better. I had a hks race ssqv on my built srt4 and loved the sound of it. The first one look like a greddy piece but is a knock off. Just don't recirculate it sounds better to atmosphere. My current build has twin tial looking ones but I believe are godspeed as well.

View attachment 1714980422
Thank you! I truthfully didnt know the difference. must be the import (shu-shu-shu-shu) vs the V8 (shhhhh-pow, shhhhh-pow) hahah
 
Thank you! I truthfully didnt know the difference. must be the import (shu-shu-shu-shu) vs the V8 (shhhhh-pow, shhhhh-pow) hahah
i just pictured the noises in my head.lol and thats some funny stuff ;)
 
My buddy and me are planning on putting twin turbos on his '88 Dodge D150 pick-up. Here is a pic of the small block Chevy headers we are planning to use. $130.00. I will get the info on these if anyone is interested.
20161016_205010.jpg
 
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