Intake fab pics

[risen]

I've been wanting to build an upper intake replacement for my car for a while and since I'm doing the exhaust header soon, now was the time. I ordered all the parts about a month ago and this weekend finally got all the parts cut and tig'd up (my brothers did the welding, I'm not that good... yet). Here's some pics. All the parts are from Ross machine racing except for lower part of flange. Upper to lower flange is 1/2" 5083 alum we had kicking around. I only had my phone to take pics with and it died before we were done, so I don't have pics of the flange welded on right now. It still doesn't have sides on it, because I'm waiting to see how the turbo sits over the tranny to decide on where/how the TB will be mounted (remote or on the plenum).

I can summarize the things I learned the hard way if anyone's looking to do this and wishes to maybe improve on what I did this time around.

[jackerman]

looks good

[GLHNSLHT2]

going on an 8v? Those "velocity stacks" are spendy, what size did you end up getting?

Oh are you bolting that onto the top of a 2 piece lower?

[risen]

going on an 8v? Those "velocity stacks" are spendy, what size did you end up getting?

Oh are you bolting that onto the top of a 2 piece lower?

I figured no one had done the velocity stacks before on an 8v (from what I could find) so I'd try it. I got the 1.75" but I'd definitely go 2.00" next time, 1.75 is just a bit smaller than the gasket on the lower of the 2pc, so the bottom of the flange will have to be ported out a bit to match the 2 pc lower. I've still got more of the mailbox tube and flange material, but I'd need to buy 4 more stacks to do another one which ,as you mentioned, is a bit expensive and I doubt I'd get the wife to go for it a 2nd time :) . I noticed the radius exiting the log on the upper 2pc is smaller than even the 1.75 stacks so I'm hoping velocity gain will more than make up for what little bit of volume I may have lost.

How did you guys machine the ones you made to accept the down pipes from the plenum? Drill press? Bridgeport?

[Juggy]

2" woulda been nice!! the size of the gasket is 1.920"

[risen]

2" woulda been nice!! the size of the gasket is 1.920"

The spare lower I have is still smaller than the gasket and just about 1.75". I think I'm just going to port the upper to match the lower. That way I don't have the runners grow and shrink too many times.

[GLHNSLHT2]

How did you guys machine the ones you made to accept the down pipes from the plenum? Drill press? Bridgeport?

1.3 million dollar Horizontal CNC machine. Got the dimensions from the stock gasket, programmed them in, made some jaws that hold the plenum material and hit the "GO" button! :) Ok so I stood at the machine and made sure it wasn't going to crash the 1st time through of course. I threaded the plenum and run socket head cap screws (allen bolts) up through the lower piece into it. Still have to have a cut off allen socket to have enough clearance between the turbo and the lower intake to be able to take it on and off while in the car. But it's doable. I just did it last week when I yanked the motor so I wouldn't scratch the nice wrinkle black off it.

[risen]

1.3 million dollar Horizontal CNC machine. Got the dimensions from the stock gasket, programmed them in, made some jaws that hold the plenum material and hit the "GO" button! :) Ok so I stood at the machine and made sure it wasn't going to crash the 1st time through of course. I threaded the plenum and run socket head cap screws (allen bolts) up through the lower piece into it. Still have to have a cut off allen socket to have enough clearance between the turbo and the lower intake to be able to take it on and off while in the car. But it's doable. I just did it last week when I yanked the motor so I wouldn't scratch the nice wrinkle black off it.

Ok, so that's a bit better than the holesaw on a drill press set to 250 rpm with a couple quarts of 10-w40 that we used. :hail: My brother has a buttload of helicoils that we're going to tap into the flange plate to make sure that I don't totally wreck it when I go in there and over-tighten it. The plan is to put my turbo over the tranny so getting it on and off shouldn't be a problem. But I'm waiting till thats done to see how I want to handle the throttle body.

You haven't done any with the velocity stacks yet, have you? And what size down pipe did you cut the holes for?

[GLHNSLHT2]

http://www.pnw-sdac.org/gallery/main.php?g2_itemId=3587 Some pics there. I cut a 45 degree chamfer into the floor. So they start at 2.42" and when they pass through the floor they're 1.920" which is gasket size and what we open the lower runners too.

[OmniLuvr]

impressive, though i was hoping that the flange was going to mount to the head. ive been thinkin about turbo over tranny also, and its gonna be a holset, so im thinkin of running t-body on the pass side to give me plenty of room (no power steering pump). i want the hy with the 90 degree outlet so i can mount the turbo with the inlet facing the front of the car (maybe a slight 30 degree angle towards drivers side?) then the compressor outlet will face the front of the omni, and the downpipe will face firewall.

[risen]

impressive, though i was hoping that the flange was going to mount to the head. ive been thinkin about turbo over tranny also, and its gonna be a holset, so im thinkin of running t-body on the pass side to give me plenty of room (no power steering pump). i want the hy with the 90 degree outlet so i can mount the turbo with the inlet facing the front of the car (maybe a slight 30 degree angle towards drivers side?) then the compressor outlet will face the front of the omni, and the downpipe will face firewall.

The problem with putting the intake straight onto the head is that, from my understanding of it, if you make the plenum the same size the whole distance, the cylinder farthest away from the throttle body will get more air than the one nearest it. I'm pretty sure that's the reason people neck them down on the end. I'm also going to use some of the room saved by the 2 piece lower for my exhaust.

I have seen intakes where the entrance is smack in the middle of the plenum (3.0L BMW I6,for instance) , but I can't even fathom what effects that would have on the center 2 ports if done to our cars. There's a thread somewhere around here where a intake for a 2.4L was built and a cad program was used to map the flow and design the intake. I have access to microstation, but I have no clue how to use it and I don't think it has the license for the air/liquid flow :(.

[risen]

http://www.pnw-sdac.org/gallery/main.php?g2_itemId=3587 Some pics there. I cut a 45 degree chamfer into the floor. So they start at 2.42" and when they pass through the floor they're 1.920" which is gasket size and what we open the lower runners too.

Ahh. I remember looking at those. Do you have any back-to-back tests between that and a factory upper? Maybe we can talk about how much you'd charge to machine some of the mailbox tube I have so I can try and do some back-to-back tests (probably not until the fall at the earliest).

[OmniLuvr]

what i meant to say is, it looks awsome! what are you putting it in?

[risen]

Lol, thanks. It's going in my CSX.

[cordes]

The problem with putting the intake straight onto the head is that, from my understanding of it, if you make the plenum the same size the whole distance, the cylinder farthest away from the throttle body will get more air than the one nearest it. I'm pretty sure that's the reason people neck them down on the end. I'm also going to use some of the room saved by the 2 piece lower for my exhaust.

I have seen intakes where the entrance is smack in the middle of the plenum (3.0L BMW I6,for instance) , but I can't even fathom what effects that would have on the center 2 ports if done to our cars. There's a thread somewhere around here where a intake for a 2.4L was built and a cad program was used to map the flow and design the intake. I have access to microstation, but I have no clue how to use it and I don't think it has the license for the air/liquid flow :(.

You might want to look around a bit on that. IIRC 8valves posted up that the intakes which slope in toward the farthest cyls. don't work so well on really high HP cars, but they mask some efficiency problems on cars that haven't been really worked over. It's been a while so I'm sure you will have to dig for it, but I wouldn't worry about making it have that slope personally.

[risen]

You might want to look around a bit on that. IIRC 8valves posted up that the intakes which slope in toward the farthest cyls. don't work so well on really high HP cars, but they mask some efficiency problems on cars that haven't been really worked over. It's been a while so I'm sure you will have to dig for it, but I wouldn't worry about making it have that slope personally.

Hmmm, good to know. Although, my car is not going to be in the really high HP range so I'd probably not have to worry about it hampering me all that much if I did it. Then, there's the question of whose high-HP range we're talking about, I doubt my high-HP range is even 1/3 of the hp the stuff 8valves deals with (not to mention that I'm not 1/50th the fabricator). Maybe next time I'll do full intake fabrication with 2.25" velocity stacks and all.

In the end it is probably more than what I'll need to achieve my goals. It was more done to allow me to move the turbo out over the tranny since I now have a fair amount of adjustment for the TB placement. Plus it was a cool project and I've become a (ever so slightly) better fab'er.

[OmniLuvr]

looks like your on the right track with your fab skillz