KA intakes

Engine, Transmission and related drivetrain.
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Yellowcar
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KA intakes

Post by Yellowcar »

So, I bought a Nissan motorsport carb manifold for my 91 KA motor however, I am not sure if it is right.
The manifold has oval shaped ports and the head has triangle shaped ports.
The manifold bolts on and I think would work so I don't know if that is just how they make them?
The upper triangle cutout is where the injector normally fits and it looks like the port on the intake would match the rest of the port.
Anybody run into this before?
Motorsport intake1.jpg
ka head2.jpg
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okayfine
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Re: KA intakes

Post by okayfine »

They likely didn't cast the injector cut-out into the carb manifold because it wouldn't be necessary with no injectors. If you wanted to get fancy you could have a KA head welded up (reverse port match?). I'd probably just generally shape the intake manifold to mimic, but not match, the head port shape.

The manifold (even with the different port shape) likely flows more than the intake valves will.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
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zootowndime
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Re: KA intakes

Post by zootowndime »

Either they didn't cast in the injector cut-outs or that manifold is actually for a ka24e. If you look at those heads they have the oval shaped ports. I had never heard of nissan making a motorsport carb manifold for a ka24de so I was wondering about that earlier when you initially posted that. I am sure you can get it to work.

The manifold will probably flow enough to get the motor the air it needs, but if something isn't done about smoothing the transition from the manifold to the head I would be worried that you wouldn't be getting the performance that you truely could be getting out of your motor. It might create some sort of velocity disturbance, but I am no engineer.
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okayfine
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Re: KA intakes

Post by okayfine »

zootowndime wrote:I had never heard of nissan making a motorsport carb manifold for a ka24de
They did, eventually. A poster here orignally clued me in to its existance.
zootowndime wrote:I would be worried that you wouldn't be getting the performance that you truely could be getting out of your motor. It might create some sort of velocity disturbance, but I am no engineer.
It's likely the port is already plenty big. Depending on the construction of the runners you might just be opening up a dead space that will slow the velocity of the intake charge. It should be port-matched to the oval of the head, but beyond that... 8)
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
datzenmike
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Re: KA intakes

Post by datzenmike »

Image

It's for a KA24DE. Compare the bolt pattern to the KA24DE intake below left.... KA24E right.

[img]http://i138.photobucket.com/albums ... .jpg[/img]

(thanks jeff, I knew this picture would come in handy) :mrgreen:
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
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zootowndime
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Re: KA intakes

Post by zootowndime »

I wonder when nissan came out with that manifold. I know that i looked for something like that when i was building my carbed ka24de but could only find them for the ka24e. Oh well , my stock intake plenum with welded on plates for the webers works great.
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duke
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Re: KA intakes

Post by duke »

When I made my intake manifold I matched the shape of the intake ports on the head to the manifold. I was able to do this because I used a 1/2" plate for the head side of the manifold, so I was able to match the port by porting into that. I'm not sure how much of an affect this divot in the roof of the intake port has on flow, but I haven't had any problems. Like I posted in your other thread, I would think that the best way to take care of this situation would be to weld up the injector divots in the head and then have the ports matched to the manifold. If I ever make another manifold (or acquire one like you just got) this would be my plan.
Duke Schimmer

'72 2-Door 510
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Yellowcar
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Re: KA intakes

Post by Yellowcar »

They used to make the KADE manifolds a long time ago then the the supply dried up. This is the first I have heard of them being available again.
The Parts book says that they are for a S14 motor but I don't see any difference between the S14 and the S13 as far as the ports go.
I was thinking the same thing about welding up the head, it doesn't seem like there would be that much to fill in order to match the port. I guess I could get the welder out and try it.... :shock: Anybody have any tips on welding the ports without completely hosing the head?
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okayfine
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Re: KA intakes

Post by okayfine »

Yellowcar wrote:They used to make the KADE manifolds a long time ago then the the supply dried up. This is the first I have heard of them being available again.
I had a friend inquire. They'll make 'em in batches of 15. Until they have 15 orders, they're NLA.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
dislexicdime
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Re: KA intakes

Post by dislexicdime »

hmmm i wonder how much they cost when all 15 are finished ?
L series only have one header!

i need another garage mine is full of part's
datzenmike
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Re: KA intakes

Post by datzenmike »

I wouldn't weld the head up at all. Doesn't offer any resistance to inflowing air and if anything would offer some resistance to reverse pressure waves. This would reduce reduce intake dilution by exhaust gasses.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
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Yellowcar
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Re: KA intakes

Post by Yellowcar »

I would think that sending the air over that ledge would introduce quite a bit of turbulence and could disrupt the air flow. HHHMMMM Wish i had a flow bench...
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okayfine
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Re: KA intakes

Post by okayfine »

Yellowcar wrote:I would think that sending the air over that ledge would introduce quite a bit of turbulence and could disrupt the air flow. HHHMMMM Wish i had a flow bench...
Turbulence is a good thing. Reduced intake velocity is a bad thing. They're not necessarily one in the same.

I'm with Mike.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
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okayfine
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Re: KA intakes

Post by okayfine »

dislexicdime wrote:hmmm i wonder how much they cost when all 15 are finished ?
IIRC, something on the order of $600 or so is the dealer list.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
510rob
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Re: KA intakes

Post by 510rob »

Fill the port eyelids with epoxy, then port them to match the manifold.

http://speedtalk.com/forum/viewtopic.php?t=327

http://www.mototuneusa.com/homework.htm
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