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Thread: Cobra Jet Intake System / Plenum for Coyote?

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    Member Dlirium's Avatar
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    Cobra Jet Intake System / Plenum for Coyote?

    I have a Cobra Jet intake on my Coyote and need something that fits the oval. What have you used?

    cj intake.jpg

    Thanks for any help!!

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    Here is a pic of how I worked it. I do not have the part number for the adapter. Seems I got it from Summit, drop shipped from Calif. It is a 5" to 4" silicone reducer. I had to shorten it to get my filter behind the radiator. A shorter/smaller filter will eliminate the cutting. I used the Spectre MAF meter housing. The cardboard is a mock up of a cold air box. The reducer is a perfect fit. Hope this helps.
    I did try a 4" alum 90* elbow. It seemed a 110* elbow might be a better fit and it needs short legs on both ends of the bend. Then you have to work your MAF meter housing in. Kenne Bell used a 4" flex hose to put the filter in the fender on their 99 Mustang Cobra kit. You can consider going through the F panel to get cool air.

    20180902_142512_resized.jpg20180902_142520_resized_1.jpg
    20th Anniversary Mk IV, A50XS Coyote, TKO 600, Trunk Drop Box, Trunk Battery Box, Cubby Hole, Seat Heaters, Radiator hanger and shroud.

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    Senior Member edwardb's Avatar
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    I'll be interested to see how having the MAF sensor that close to the throttle body works. Pretty sure Ford (and others) recommend it should be further away and in a smooth air stream. A tune will detect whether the voltage from the MAF is sufficiently stable.

    Different note, nice work planning for actual cool intake air. I've watched the Intake Air Temp (IAT) data closely on #8674. I was concerned how having the air cleaner open in the engine compartment would affect IAT and whether I should consider a similar approach. There's no question the air is warmer than ambient (AAT data) but it's not as much of a difference as I thought it would be. Usually 15-20 F above ambient. Probably affected by the relatively cool running Coyote (compared to some other engines) and there is quite a bit of open air flowing through the Roadster engine compartment compared to, for example, a Mustang which is much more dense. I don't know how much HP I'm giving away, but I suspect it's not much plus for my driving I have no shortage of HP as it is.
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    It seems Ford suggest 3 times the tube diameter for the distance of the MAF sensor from the butterflies.
    I know I am short now, but might go with a shorter filter, if there is an issue. Ford has used a screen inside the air flow tube to smooth out any pulses. I still have the 90* tube as an option.
    On the oval tube adapter, I think someone makes the 5" rubber tube with a 90* elbow. It may have been under some diesel engine products.
    Last edited by Railroad; 10-07-2018 at 05:34 PM.
    20th Anniversary Mk IV, A50XS Coyote, TKO 600, Trunk Drop Box, Trunk Battery Box, Cubby Hole, Seat Heaters, Radiator hanger and shroud.

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    Member Dlirium's Avatar
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    Thanks for the help guys! I did find the PPE adapter that you have, but yeah - a 90 in that would be better. then 12" to the MAF - don't know if I'll have that much room, but I'll give it a shot!! Anyone have pictures of their MAF / Air Intake setup pointing down?

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    Tom's 33 is changing his oval CAI tube and has his old one available. I think it points down with some off set. Check out his build thread, post #350. It would put the filter in front of my radiator air wash.
    20th Anniversary Mk IV, A50XS Coyote, TKO 600, Trunk Drop Box, Trunk Battery Box, Cubby Hole, Seat Heaters, Radiator hanger and shroud.

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    Here is what a 90* 4 inch tube looks like. As said before, I think a 110* bend would give you more room and the legs need to be shortened on both sides of the bend.

    20180823_183527.jpg 20180823_185753.jpg
    20180823_185347.jpg
    Last edited by Railroad; 10-08-2018 at 10:49 AM.
    20th Anniversary Mk IV, A50XS Coyote, TKO 600, Trunk Drop Box, Trunk Battery Box, Cubby Hole, Seat Heaters, Radiator hanger and shroud.

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    Senior Member Dave Howard's Avatar
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    Quote Originally Posted by Railroad View Post
    It seems Ford suggest 3 times the tube diameter for the distance of the MAF sensor from the butterflies.
    I know I am short now, but might go with a shorter filter, if there is an issue. Ford has used a screen inside the air flow tube to smooth out any pulses.
    3 pipe diameters is required away from a disturbance in the pipe to achieve flow measurement under laminar condition not turbulent. Turbulent conditions will result in erratic, erroneous flow measurement. A disturbance in the pipe is a bend, valve or change in the pipe diameter. The screen helps to reduce turbulent flow.
    MkIV #7854, Kit picked up September 2012, Coyote/BOSS 302 intake tuned at 488HP, TKO600, Center Force, Moser 8.8, driveshaft safety hoop, Stainless Header 4x1x4 headers, Gas-N-sidepipes, rad shroud, Wilwoods, NO PS/PB, heater/defroster, heated seats, wipers, Herb door panels, Dynamat Extreme sound/heat dampening, premium Rodtop top, Fast Freddie lexan wind screen, Nitto 555R, drop trunk battery, drop trunk storage,

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    Is the three times pipe size go fore boost to? On 5-inch pipe that is fifteen inches-- no way will that happen!
    Will have two - two /half pipes coming together then into CJ intake that is = five inches.

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    Page 8 of this document should answer most questions, correctly.

    http://latemodel.cachefly.net/downlo...6017A504VA.pdf.
    20th Anniversary Mk IV, A50XS Coyote, TKO 600, Trunk Drop Box, Trunk Battery Box, Cubby Hole, Seat Heaters, Radiator hanger and shroud.

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    Senior Member Hacksaw84's Avatar
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    I asked Tony from FFR what they use and he said:

    "I get the tube from silicon intakes and it’s a 5” that you can oval out .. www.siliconeintakes.com/"

    I am not a huge fan of this and looked into finding a better solution but didn't have any luck. When I talked to Lund racing about eventually tuning the car they wanted a photo of the intake, the diameter, clear photo of the maf location.

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    I bought the Ford kit for plumbing up the A50XS. Over $300, it has a nice tube that will mate to the TB, but after the 90 bend it tapers. To shorten it you will be dealing with a tapered tube to make your silicone sleeve onto. The end of the tube as shipped reaches the F panel with no filter. I had to return it.
    20th Anniversary Mk IV, A50XS Coyote, TKO 600, Trunk Drop Box, Trunk Battery Box, Cubby Hole, Seat Heaters, Radiator hanger and shroud.

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    Senior Member Hacksaw84's Avatar
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    Quote Originally Posted by Railroad View Post
    I bought the Ford kit for plumbing up the A50XS. Over $300, it has a nice tube that will mate to the TB, but after the 90 bend it tapers. To shorten it you will be dealing with a tapered tube to make your silicone sleeve onto. The end of the tube as shipped reaches the F panel with no filter. I had to return it.
    Yeah I have the Ford Racing intake (it came with the cobra jet manifold when I bought it) and I am sure its too long. It also has the tapered end so trimming it wouldn't work.
    https://www.americanmuscle.com/frpp-...ai-1114gt.html

    I have thought about getting a pmas intake b/c it looks like the tube keeps a constant diameter after the 90 bend and the sensor goes on the filter end of the intake. That might allow you to cut out the middle area. But its an expensive part to cut and see.
    https://www.cjponyparts.com/pmas-cob...yABEgKLzfD_BwE

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    Hi, did you end up keeping this straight pipe design or change it to lengthen the distance between the MAF and the throttle body?

    Quote Originally Posted by Railroad View Post
    Here is a pic of how I worked it. I do not have the part number for the adapter. Seems I got it from Summit, drop shipped from Calif. It is a 5" to 4" silicone reducer. I had to shorten it to get my filter behind the radiator. A shorter/smaller filter will eliminate the cutting. I used the Spectre MAF meter housing. The cardboard is a mock up of a cold air box. The reducer is a perfect fit. Hope this helps.
    I did try a 4" alum 90* elbow. It seemed a 110* elbow might be a better fit and it needs short legs on both ends of the bend. Then you have to work your MAF meter housing in. Kenne Bell used a 4" flex hose to put the filter in the fender on their 99 Mustang Cobra kit. You can consider going through the F panel to get cool air.

    20180902_142512_resized.jpg20180902_142520_resized_1.jpg

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    Quote Originally Posted by Madfor67 View Post
    Hi, did you end up keeping this straight pipe design or change it to lengthen the distance between the MAF and the throttle body?
    I could not use the short straight cold air tube. My engine would die after a hard pull and letting off the gas pedal.
    Tuner said the MAF sensor was too close to the Throttle body.
    I used a 4" alum 90* tube and put a smaller air filter on it.
    It seems, I was told 11" minimum from MAF sensor to Throttle body.
    I also put an air dam between the radiator fan the air filter.
    Tuner told me the turbulent air off the fan, might upset the idle.
    20th Anniversary Mk IV, A50XS Coyote, TKO 600, Trunk Drop Box, Trunk Battery Box, Cubby Hole, Seat Heaters, Radiator hanger and shroud.

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    I worked with Guy Smith at Spectre Performance to put together components that would fit and look the way I wanted them to. Spectre Performance is a K&N company. Guy will work with you to assemble components to meet your needs based upon the intake, distances to radiator and other obstructions. This is what Guy does, his job with Spectre. My application was a 2nd Gen Coyote in a 1970 Mustang Fastback restomod. So my solution was definitely custom and the cost reflected that. Guy knows the Factory Five cars, so he should be helpful in putting together a solution.

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    Thanks for the insight! I really like your straight setup, but I guess that’s a no go… Just got my cobra jet intake with the twin throttle body. I also have JLT 90 degree cold intake pipe. I guess I’ll try to mate that with my spectre MAF housing. CEFCC4C1-6E1C-4057-82A1-5A4FACFFAE90.jpeg

    Quote Originally Posted by Railroad View Post
    I could not use the short straight cold air tube. My engine would die after a hard pull and letting off the gas pedal.
    Tuner said the MAF sensor was too close to the Throttle body.
    I used a 4" alum 90* tube and put a smaller air filter on it.
    It seems, I was told 11" minimum from MAF sensor to Throttle body.
    I also put an air dam between the radiator fan the air filter.
    Tuner told me the turbulent air off the fan, might upset the idle.

  21. #18
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    It’s good to know that I have an option. If my own setup fails, I’ll reach out to him. Thanks!

    Quote Originally Posted by Alan_C View Post
    I worked with Guy Smith at Spectre Performance to put together components that would fit and look the way I wanted them to. Spectre Performance is a K&N company. Guy will work with you to assemble components to meet your needs based upon the intake, distances to radiator and other obstructions. This is what Guy does, his job with Spectre. My application was a 2nd Gen Coyote in a 1970 Mustang Fastback restomod. So my solution was definitely custom and the cost reflected that. Guy knows the Factory Five cars, so he should be helpful in putting together a solution.

    [email protected]

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