Making a custom lower intake

V6Sprout

Registered User
I am gonna try and make a lower intake to fit the SC roots blower to split port heads. The split port heads came ont he 99+ mustangs and 97+ F150's. The spilt port runner design netted 40 HP gain on the N/A V6 mustang motor. I have seen these heads net a 75 HP gain on a supercharged motor. So I am curious to see how they will affect power on the roots blown motor. I am basically gonna copy the original single port lower but have the end flanges have the openings for the split prt heads instead. Morana started one a year or two ago but never finished. I finally got some split port heads and intake to work with. Here are some pics.

The Fuel rail shoudl not be a problem as I will use the F150 rail reverse mounted. Just gotta get the blower high enough to clear it. I cut up the F150 intake to see what it looks like inside. The cooling channels are different, on the single port they run straight across the front of the lower intake, but on the spilt port heads they run down the center of the lower and across at teh front and back. On my intake I will just ahve it run across the front, as the rear opening are blocked by the gasket anyways and the coolant will just heat the intake anyways. If the stock SC lower has it just across the front then this one will be fine.

First I cut the flanges off the lower so I can use them as templates for making new ones.. After this I will make a lower plate for the intake, then fab up the cooling channels and then thermostat housing section, then the top level for hte blower to sit on and the rear opening for hte air to come in. Here are the pics.

Flanges cut off and intake split down the center

f150_lower_cut_in_pieces.jpg


Flanges

stock_intake_flanges.jpg


Thermostat housing removed

thermostat_section_cut_off.jpg


Center section split apart

f150_lower_cut_down_the_middle.jpg
 
Better view

f150_lower_split_apart.jpg


Close up up coolant channel and EGR channel, the EGR things in the secondary runners are just stuck in the holes, so they can be pulle dout easy, they just have 4 little tabs holding them in place.

egr_tabs_inside_view.jpg


Fuel rail mounted

f150_fuel_rail_reverse_mounted.jpg


f150_fuelr_ail_reverse_mounted_2.jpg
 
I've looked for a set of heads/intake locally but none around that are wasted enough to get a good deal on. How about restrictors in the front water passages on the heads so more water will get drawn from the rear?

That way, the rear of the head would get a little better cooling. Currently, there's not a whole lot to encourage the water to the rear of the block & up into the heads. With restrictors there might be more flow in the rear(?)

This makin' any sense?

'bird
 
V6Sprout said:

If you look at these three pics it will show the water passage. In the 3rd pic, the water passage comes out the head at the front of the block right below the second port. If you look at the rear water passage the intake gasket blocks it (right below the last port, black area on gasket). Now looking at the lower intake you can see how the water channels from the front right to the back of the lower intake, but again the intake gasket blocks this and doesn't allow any coolant back there, but there is a small pin hole in the gasket to allow a very liittle amouint through. When I amke the lower I thought about just having it run across the front since it can't get through the back anyways. What are you thoughts here?

Also having the coolant passage go through the entire lower intake wouldn't this heat back up the incoming air that the IC just cooled down? This is another reason I thought of just having the coolant passage go through the front of my new lower intake.

Give me your suggestions and ideas guys, I want to make this a well functioning lower and possibly make more in the future for others.
 
V6Sprout said:
and possibly make more in the future for others.

If you do, consider me very interested. I sure wouldn't mind throwing a spare M90 on my splitport 94 LX.

06160010.jpg



-Rod
 
humm, this is gonna be a little harder then I thought, but I am still gonna do this. The fuel rail I posted above doesn't look like its gonna work, sits too high, the spot thats the problem is the area where it goes under the blower, on ours the rail dips under the blower, so I would have to really raise the blower up to clear this rail, plus at the back it looks like it owuild interfere with the rear intake, hummmm.

The other problem I am gonna have is the mounting of this lower intake, the mouinting holes are not all across the top of the head like on ours, they are staggered, some are at the bottom of the head. I may have to make a removeable lid to the lower intake in order to access the mouinting bolts, then make a mounting lid that seals up, not too hard just extra work, DOH!

Like I said before though, its a slow process and hopefully I can get it to work.
 
As far as cooling in the rear of cyl..I tap the manifold where the water passages are for flow acorss from head to head..Works on teh ford V8's
 
V6Sprout,

I don't know if this will help you, but I used a E-150 fuel rail when I did my splitport swap. I had to make two brackets to mount the rail to the lower intake because two of the mounting holes didn't line up with the splitport lower intake holes, but other than that it worked out great. I believe that it sits lower than the rail you're working with.

-Rod
 
I can see the benifit of this swap on a n/a motor but dont,
see how its going to add to the hp on a supercharged motor,

the head still has one valve for intake and we have not reached the flow cap on our current heads intake ports.

as the valve can only flow so much air ,
I beleive the purpose was to creat high velocitys on intake port,
for na to ram air into cyl,

and atomize fuel in a high velocity stream. but please explain how this n/a technologies will help on a pressurized motor ,

am I missing something here?
 
I don't know for sure it will help, but I do know poeple running these heads on mustangs with power adders are making HUGE HP. We have one guy who made a custom twin turbo setup and ran 11's on the stock motor, no mods to the motor except the turbo and injectors and MAF and slightly larger TB but still smaller then ours.

I also swpped these heads onto a Vortech mustang and he gained 75HP from the swap. Now with the way the lower intake on our motors is, there are no real runners like on these intakes, so it may not have any effect at all who knows, but we'll find out after the swap. The project is more for fun to see if I can get it to work and see if there is any benefits out of it.
 
Imk not being negitive I was just wondering I too have looked at them with interest and i will be keeping a eye on this subject,

too bad ford didnt make any four valve cyl heads. for our 3.8

or overhead cam we would be in hp heaven.
 
Perhaps a pancake type manifold for the split port will do..Much like our factory SC intake..Would be easier to fabricate..Good ;uck!
 
Manny you brought up a good point, I knew you were not being negative but more inquisitive (sp?) :)

Damon, I plan to make it a pancake style like the factory one, but I have to take into consideration the cooling ports are placed farther back on htese heads, not quite at the front, and the mounting holes are staggered, some at the bottom of the head. I hope to make a removable lid on the intake to allow access to these bolts, just gonna take a bit more planning thats all. A custom fuel rail is looking a lot easier then finding a factory one to use. I heard the E150 rail may work so I"ll check into that as well.

Kepp you ideas coming folks, I welcome any advice, all ideas will be appreciated, good or bad, let me know what ya think.
 
I firgure I can worry about the rails later, probably do like what you suggested, make custon end piece to attach each rail to each other.
 
I have made good progress on the custom intake today. Making a prototype out of acrylic. So far I have the flanges made, the front and rear, top and bottom. Still need to make adjustments to each but its rough. Looks stinkin cool so far.

The one mounting part for the blower is almost directly overtop one of the ports so that will be fun, also need to get a hold of a stock SC lower so I can measure how high the blower sits and how far forward, doing it by eye won't work, its gotta be exact. My lower is still on the car, so I am gonna see about getting a spare from a local SC guy. So far its been fun, I am covered in little acrylic shavings, but it smells cool.

How much room do you guys have betweent he blower top and your hood? I know you have enough room to put a rasied top on, but how much more room do you have. I may have to raise the blower up a bit higher then stock and want to make sure it woudl fit under your hoods if I ever make copies of it. Right now I am just making for my stang for fun, to see if it helps HP at all. I have a cowl hood so it will fit mine regardless.
 
If you're going through all the trouble to make a new intake, why not make it an inverted setup with an air/water IC in it?
 
the more I look at my prototype the more I think about that as well. We'll see what I can come up with. What type of Water-to-air IC is available, where can I go to look at different cores? any idea's?
 
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Take a look at the Cupranickel units made by Garret, Thats what the Lightnings use in there intakes. But be prepaired to take out a second mortgage on your house, the last time I priced them they were 2-3 times higher in price than a very healthy FMIC core.:)
 
thats what I was worried about and why I orginally didn't intend on a flipped version. I am still working on my orginal design, but may still consider the flipped style as well, we'll see. Got alink to a website for those intercoolers?
 
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