....so I'm thinking about making my own cold air intake for my daily 86 WS6 TA. Its got the 5.0 TPI motor with some upgrades(see sig) and hooker headers that are on their way. I have a temporary PVC 3" intake with a K&N filter on there now, but thats only until I fab up my stainless 3 or 3.5" intake. A few questions....what wall thickness should I get for this setup? I would be getting it from a local steel/aluminum supplier....and also how do I go about polishing stainless steel so that it comes out shiny like chrome? I've never polished anything in my life before, thats why I'm asking. And i'm also indecisive about the 3.5"....would 3" be enough for would 3.5" be more beneficial? Some help and information would be grealty appreciated. Thanks everyone.

 

3" is enough when it comes down to mandrel bends.
If you are going to crush bend it, go with the 3.5".

 

Not exactly sure what cursh bending is or mandrel beds are and where I can get it done. I heard with stainless, you cant really bend it b/c it will kink. What i want to do is have a 90 degree bend where it goes into the rubber boot in the front of the throttle body....from there, it should go under the two radiator hoses on the passenger side...where i will attach the MAFS via rubber boot and clamps. Then i attach the air filter. I still need some advice on:

*Wall thickness of the stainless tubing
*How to polish stainless tubing
*What i should do to make my 90 degree angle

Thanks guys/gals.

 

Oh. Well if you are connecting different sections of tubing with silicone/rubber boots, than I would go with 3.5" - It may seem like overkill to some, but the extra diameter will alleviate the turbulence at each connection. As far as thickness goes, you don't need much. To get an idea, go take a look at Autozone's "import cold air intake" tubes...

FYI: A crush bend is a standard bend where the actual diameter of the tubing shrinks. For example, a crush bent 3" diameter tube is only 2.6" at the bend. A mandrel bend is a special bend where the diameter of the tubing is constant. For example, a mandrel bent 3" diameter tube is still 3" at the bend.

I don't know much* about polishing.








*I dont know anything about polishing whatsoever

 

Thanks for the explanations about the bending. Your explanations were very helpful. I will need a mandrel bend then on the 90 degree part. I understand that the wall thickness should be the same as those crappy intakes you buy at autzone for hondas and such, but i need to know specifically the size/measurement for what i need to do, b/c the supplier needs to know this as well....for example: 11/32nds, etc. If anyone out there has that information, and also about polishing, that would be great. Thanks.

 

I used 3" mild steel mandrel bent tubing from http://www.westcoastbending.com online. I believe the walls are .065, but I'm not sure since it's been almost two years since I ordered the bends. I ordered 20 bends at $10 each back then. Use their "request a quote" form and they'll get back to you.







If all you're doing is making one pipe for yourself, get the aluminized steel mandrel bent pipes from J.C. Whitney. They're fairly cheap and have tons of things in stock. Even though most of their car products are cheap P.O.S. crap, the pipes are good.

 

Bnoon..

Thanks for the link and the advice. I will be checking them out today, and see what I can come up with.

 

Ok, i checked out their site...some decent info there. I plan to however go with the local distributor of aluminum/steel/stainless steel...the prices here arent bad. I would just like to verify that to .065 wall thickness would be a good thickness to go wtih, as I believe its not a good idea to go too thin or too thick....thinner makes it less strong, and too thick makes it too dense which = heavy. I will need one 90 degree mandrel bend. I have no idea about wall thicknesses, thats why i'm asking and double checking. So if someone could please verify the wall thickness of .065 or whatever is the most reccomended for stanless steel 3" tubing. Also, i need some adivce on polishing stainless steel. Thanks a bunch.

 

No problem, buddy! That's why these boards exist - transfer of knowledge and advice is a beautiful thing!

Bnoon - THAT IS AN AWESOME POWDERCOATING ON YOUR TPI SETUP! Looks fantastic!!

 

Anyone else have some info on a good/reccomended wall thickness for this setup and polishing advice?

 

Polishing is easy. If you have ever waxed or buffed your car, its the same principle. Welding supply stores have lots of polishing stuff. They sell it to Fab shops to polish all that fancy stainless stuff they build for log trucks and such.

 

I just remembered that I know a guy who has a shop that could show me how to do it...so thats taken care of. Now i just need wall thickness reccomendations if anyones got them. Thankx.

 

TTT

 

Wall thickness is very, very UNcritical. Just use mandrel bent pipes and you'll be A.O.K.

 

I just dont want it to be too thick, so I can flow more air. Also, I have to tell my supplier what wall thickness I'm looking for...because they will ask me and I will be like Who can do mandrel bending? Can a muffler shop do that?

 

Get the premade mandrel bends or you'll spend twice as much getting it done at a shop. Only a select few can do mandrel bends... all others use the nasty crush bends.

 

I think i know someone who will do my mandrel bend for cheap. By the way bnoon.....your 86 Trans Am looks EXACTLY like mine....silver paint, red stripe, grey ground effects, t-tops, WS6 package

So i was looking in my JC Whitney Catalog today....and found 3" diameter T304 stainless steel tailpipe tubing. Thats 3" O.D.....which is 16-guage. For a 3-foot length of this stuff, its $44 bucks. I'd have to also polish it myself. Just was wondering if this stuff would work well for my cold air intake that I want to build? Thanks.

 

That will do the trick, bud.


...as long as you're getting mandrel bending cheap (nice!).


3" mandrel bending and an open element filter in cool air should see you a good gain throughout the powerband. However, it is an 86 and has the infamous peanut cam I suspect. If it does, you won't see as much a gain compared to the better LB9 cam.

 

It DID have the peanut cam...(I think-had whatever the stock '86 TPI motos came with)....but I upgraded the cam to a Crane Cam CompuCam....its in my sig. When I did that mod, it definetly helped alot by adding it to the mix. I only need one mandrel bend, and this guy bends stainless steel all day long and can make anything I want....so it should work out alright

 

Glad to hear it!

 

Heheheh, it's gloss black paint on the CAI! I will be having powder coated goodies on the LT1/305 engine I'm building though. I just ordered the powder today in fact... Gloss red will make it look more like the LT4 engine (as well as having Corvette plastic engine covers) and the red will also go well with the stock stripes on the car.