The Steeda front STB on my 2010 is 4130 chromolly..and I believe its aprx 1", or 1.125". It has 2 bends on each side, 4 in total. Steeda also makes another stb, with only 1 bend on each side. Both of em fit over top of either a M90 or tvs-2300 blower on the 2010 car... and the 2300 blower on the 11+ cars...with loads of room for the hood closed.
The local race shop that builds all the tubing chassis's for sprint cars and roll cages for sprint + stock cars..have no kinks in anything... but they are using bigger diam tubing...like 1 5/8" and bigger. They use both 4130 and also DOM tubing.
One trick that works well when bending tubing, is to 1st pack it with either sand....or rocksalt. Zero kinks everytime. The rocksalt /sand is easily removed when all done. Walker2GT put a light + go-pro camera in the eng bay..then closed the hood on his 2010.... to verify hood to stb clearance. You may want to do that 1st..with a real short steel ruler, to verify exact distance you have between blower and hood....then design around that. BTW, the stb's will clear the VMP-1900 blower per vmp.
Another option is to use steeda or similar eng mounts. They allow for a 0-.25-.5-.75" eng drop. I used the .25" drop. My stb was just touching the airtube b4 the new eng mounts installed. I think on the FRPP big whipple kits for the GT-500's, they come with the blower kit. I believe you can only go so low with the emg mounts....till you have issues with the LT's hitting the steering shaft. I have zero clearance issues on my 2010 with JBA LT's + .25" eng drop.
IF you can get a custom STB made, that's good. The big advantage of the steeda stb is its adjustable length at both ends. It also has spherical's on each end. The stb can have it's transverse bolt removed from either end..so the stb swings up, out of the way. Or it can be removed altogether. It uses all 4 x studs on each shock tower... instead of just two. And no slotted holes either. The thick steeda mounts are a snug fit around the 4 x studs. The beauty is... they don't have to be touched when you want to pivot the stb at either end. Of course, due to tolerances between cars.and spacing between shock towers, the length on the steeda stbs has to be adjustable.
To make a custom stb easier.... you could always have a round plate welded to the 4130 at each end..with 4 x slightly slotted holes. If you measured dead on b4hand, you could just have the 8 x holes drilled /punched dead on..so its a perfect fit...for your car.
