(S//NP)Mandrel tubing source

[CTX-SLPR]

Howdy,

So I'm in need of some piping for the custom intake I'm going to build for my Bonneville LSR motor. I need 2in mandrel bent, 18-16ga mild steel pipe, mid to large radius bends are fine. Plan is to take U-bends and chop them up with a band saw into 45 and 90 sections that are needed. It always seems cheaper to buy U's and chop them up and with a bandsaw this time I should be able to get clean and precise cuts vs. what I got on my exhaust with a chop saw.

So far looked at:

https://www.summitracing.com

https://www.spdexhaust.com

https://www.wolfaircraft.com

https://www.mandrel-bends.com

Columbia River (Mandrel-Bends.com) looks to be the cheapest and on an intake I'm not terribly worried about the reputation for them to be "thin on the outside wall" that I've read about from people on the turboBuick board for building exhausts.
As to why steel for the intake... Mainly because I can weld it myself, it's cheaper, and easier to make modifications on it. If I had a TIG, I'd make it in Al.

Thanks,

[Monk]

Have you tried these guys?

http://www.schoenfeldheaders.com/

We used their kit for the headers on the 409.

[CTX-SLPR]

$0.25 cheaper than Columbia River and in a wider radius too.

Knew it was worth asking!

[DanStokes]

Might be worth looking at Speedway Motors. I think it's speedwaymotors.com but you can Google if that's wrong. They have TONS of stuff.

Dan

[SuperBuickGuy]

I use Mandrel-bends for all of my tubing purchases because they're very quick shipping, and once you're on their mailing list - they have great scratch and dent deals.

[Barry Donovan]

Might be worth looking at Speedway Motors. I think it's speedwaymotors.com but you can Google if that's wrong. They have TONS of stuff.

Dan

I just got their catalog.. wow. Never got that one before. My stainless j bends were "vibrant", maybe type the brand and see what cheaps up.

here is link to the source, but I did not click my way to process.

[cantvalve16]

SPD puts out a nice product and they ship quick.

[Beagle]

2" tubing is huge for an intake on a 3.0 liter ...You might want to add some smaller stuff to your list. BOSSMAN might have some input for this, but my thinking is your gonna lose power in any usable RPM range. Boost may overcome some of that, but my thought on boost is build the best NA motor you can then add boost. I'm not saying don't do it by any means, just thinking out loud. Good luck!

[Orange65]

You might take a look at these guys. I haven't compared prices recently, but I still have these guys bookmarked from building my headers earlier this year.

http://www.verociousmotorsports.com/Shop-by-Category/Mild-Steel-Mandrel-Bends/180-Degree-Mild-Steel-Mandrel-Bends

[Monk]

2" tubing is huge for an intake on a 3.0 liter ...You might want to add some smaller stuff to your list. BOSSMAN might have some input for this, but my thinking is your gonna lose power in any usable RPM range. Boost may overcome some of that, but my thought on boost is build the best NA motor you can then add boost. I'm not saying don't do it by any means, just thinking out loud. Good luck!

Step headers maybe?

[CTX-SLPR]

Step headers maybe?

Monk,

This is the intake, headers are already admittedly too big to help reduce back pressure at high RPM. In either case a soft bottom end doesn't seem like a bad thing based on things I've read from current Bonneville racers and watching in car videos from Roadkill and other racers.
I've been debating back and forth on the tubing size for the intake. The 2in is based on the port size in the intake gaskets most commonly used on performance Buick V6 applications. It's very close in perimeter to 2in tubing's circumference. I have been thinking about going down to 1 7/8in tubing and using the extra space to fit the twin injectors into the port.

[Monk]

Monk,

This is the intake, headers are already admittedly too big to help reduce back pressure at high RPM. In either case a soft bottom end doesn't seem like a bad thing based on things I've read from current Bonneville racers and watching in car videos from Roadkill and other racers.
I've been debating back and forth on the tubing size for the intake. The 2in is based on the port size in the intake gaskets most commonly used on performance Buick V6 applications. It's very close in perimeter to 2in tubing's circumference. I have been thinking about going down to 1 7/8in tubing and using the extra space to fit the twin injectors into the port.

Gotcha........

[Barry Donovan]

schedule 40 aluminum "1.5 inch nps".. 1.9 inch O.D.

that is where I am ending on my own 2.65 inch stroke. Read it all as two inch, but actual numbers are different. The velocity kept on a thicker gauge etc etc. alot of trial and error.

Just rambling, that is what the net is for.

[NewEnglandRaceFan]

Monk,

This is the intake, headers are already admittedly too big to help reduce back pressure at high RPM. In either case a soft bottom end doesn't seem like a bad thing based on things I've read from current Bonneville racers and watching in car videos from Roadkill and other racers.
I've been debating back and forth on the tubing size for the intake. The 2in is based on the port size in the intake gaskets most commonly used on performance Buick V6 applications. It's very close in perimeter to 2in tubing's circumference. I have been thinking about going down to 1 7/8in tubing and using the extra space to fit the twin injectors into the port.

might be worth it to make a two piece intake, and one lower half with the 2" and another with the 1 7/8th
I'd think, and could be wrong, but I'd think it be better to make the lower end "soft" with turbo size or low rpm bleed off than with oversized intake ports , and ware you are jamming the air through the ports you don't really need the extra volume, you need air speed and it sized as close to the intake valve dia - stem I'd think would be the e ticket or the ports i.d. (in the heads)at it's smallest spot..
like I said at the start I could be totally off,