Fresh air induction intake......
 

Hi, does anyone have a way to plumb the mass air sensor air intake piping to get its air from outside? I'm a firm believer that taking air under the hood is very detrimental to engine performance and stability. For example, whenever the cooling fans start you can feel the engine's idle change (for the worst). I know that there's not much room for a cool air-box but I believe that it maybe possible to plumb the induction to get its air from outside. Does anyone have experience with such a design?

ls7 intake pulls air in front of radiator


https://www.v8miata.net/attachment.p...ine=1373499631

Unfortunately, wrong engine.....
 

I have a 5.0 Liter Ford in a NA body; I wish that it was that easy with a centered front throttle body.

Cheers!

I've got a Ford engine and managed to get cold air in... but it's carbureted and I have an aftermarket hood. Sorry, I know that doesn't help you. ;-)

https://www.v8miata.net/attachment.p...1&d=1373522900

Actually easier. There are pictures of mine in the gallery.

https://www.v8miata.net/engine-perfo...-location-705/ Try that. I listed parts in the fifth post.

I modified my headlight lids to stop where I want them. I found that leaving them up about 1" lowers my intake air temps by 40 to 50 degrees while datalogging. So I don't look so SoCal with headlights in the "sleepy" position, I plan to make up a NACA type intake scoop in the passenger side headlight door and create a airbox behind it. Hopefully this will replicate the effect while not introducing extra air into the engine bay via the "sleepy" lights.

-Jason

I am going to make it a priority project and be hard headed about it, because I know from experience that taking air inside a hot engine bay with some off and on air disturbance will drive the ECU to do some crazy adjustments. The more I look at the photo in Mazdaspeedmiata's answer above, the more I think that with the proper engine billet accessory drive mounts, something could be engineered for the NA series?!?!?!

On my Ford conversion I routed my intake into the passenger front fenderwell by cutting a hole under the headlight. The intake filter is located in front of the tire and gets incoming air from the grill opening. Made a fender liner to protect it from road splash and debris. Seems to be working fine and was inexpensive to make. It's not the perfect solution but it gets the CAI out of the hot engine compartment.

Topdownfun, is it possible to get some photos of your modification? This is basically how I wanted to run the duct work but I wasn't sure if the space was adequate. I also want to relocate the air intake temperature sensor away from the intake. I know that shinny aluminum duct looks pretty but it also absorb lots of heat; an assortment of plastic duct from donor cars would also be nice to route and isolate the air charge from engine bay heat soak.

Jacko (MGB-V8)

Mine's a 95 Miata with a 95 Mustang GT engine (SN95) so my intake is a little different from the typical fox body swap. I'm out of town and don't have any pictures handy, but here's a link to an older video that shows the intake near the end. I had to cut a small brace on the back of the headlight bucket but overall it wasn't that hard to do, and cutting the hole in the fender liner was pretty easy using a jigsaw with a metal blade.


TM

Don't your light interferes when it flips up?

4 inch tubing interferes with the light mechanism--you have to keep the headlights up all the time-- but not 3 inch. 3.5 inch would probably work, if some could be located.

Regards,
TM

LEEBO, has a nice fresh air induction system, but it's easier to do because of the carburetor. Pro-M makes a similar single plane EFI intake with multi-port injectors that might be the alternative answer to Ford's EFI intake and the large upper intake. Almost all Ford sensors can be retained. The shorter runners would also raise the horsepower band to upper RPM but in a light car such as the Miata, you may not notice the lost in low end torque?!?!

My 2 cents (unproven)

Leebo, What hood are you running and where did you get the aluminum shroud to go around the air cleaner that seals it to the hood. My build is similar and this looks like a nice clean solution.

The hood is a Simpson Design cowl hood w/ louvers (Simpson Design 1st Gen Miata Accessories). I did some body work to my miata about 10-11 years ago including this hood... well before the V8 conversion. The cowl happened to work out to be a convenient way to channel cooler air in to the carb. That metal pan was a custom piece I designed and had made locally. I basically took some poster board, foam board and a bit of my son's play-doh to mock-up a pan design to fit the profile of the hood when closed, then handed it over to a friend at a shop to measure it, cut it out and have it welded up. Not sure if he still has the CAD files to reproduce, but probably.

https://www.v8miata.net/attachment.p...ine=1374515829

https://www.v8miata.net/attachment.p...ine=1374515829

https://www.v8miata.net/attachment.p...ine=1374515829

https://www.v8miata.net/attachment.p...ine=1374515829

https://www.v8miata.net/attachment.p...ine=1374515829

The cowl in that type of setup is meant to vent air out. As the air rushes into the front and also over the hood it is meant to pull the heat out and up the windshield. Have you ever had issues getting proper air flow coming in the cowl at speed?

Don't get me wrong, I love the design, just seems a little backwards in the engineering aspect.

Actually that is the best place to get fresh air to the intake since it is a low pressure area. That is a very similar design to those found on all of the Sprint Cup & Nationwide cars. I like it.

WolfGT, sorry but I think you're mistaken on that. I agree that it looks like it would be a spot where air would be drawn out, but that's just not the case. There have been tests in the past that measure the pressure in various areas of the hood and that spot is a low pressure area. In theory, you would be better off blocking that cowl to get better air flow through the radiator. The louvers on the top of the hood are higher vacuum and draw air out. The idea I had with sealing the cowl to the carb was to not only provide a cool source of intake temps, but to get it from a spot that air slightly wants to blow in, and to allow for better cooling through the radiator.

Great information! Like I said, I love the design. Now with that information, it makes me want to do that even more.

Leebo, if you have a source that may have the design on file and would be willing to make one, I would greatly appreciate the lead.

One other on topic thought about cold air. With a 302 carb setup, is there enough room between the hood and distributor to put an elbow on top the carb and pull from an intake setup like shown on the LS at the beginning of this thread?

Elbow like this:
https://www.v8miata.net/attachment.p...ine=1374531560

This is my set up. I checked before I did this and it will fit behind the bumper.

I'm checking on that. I'll post back with what I find out.

Hmmm... looks like that would be a really tight fit between the hood and distributor; I don't think it would work. Perhaps go around the side of the distributor instead? Looks like it would be tight either way.

A quick question about the LS intake. I can't tell by the pic (the blue car at the beginning of this thread), but what about the hood latch? Are there hood pins or something of that sort?

Most guys use aero latches