new intake mainifold

Post by **NewYork240** » Thu Feb 20, 2003 8:21 pm

It seems like a well made performance intake manifold would provide a decent amount of power for the KA, but I haven't seen any. Does anyone know if one is made for the KA ?

Post by **I am Technoman** » Thu Feb 20, 2003 8:21 pm

Just bore out the stock one.

Post by **Aries** » Thu Feb 20, 2003 8:21 pm

RevHard used to make them custom...

Though truely anyone with welding skills could make one for next to nothing.

Post by **Scott McLellan** » Thu Feb 20, 2003 8:21 pm

Would you want to keep the original design with the curve around thing? How hard would it be to port the stock intake? Think you could get a rotary tool in around the inside radius? (Wouldn't you want to concentrate on the inside radius?) Know anywhere where you can buy mandrel bent aluminum piping? Sorry so many questions.

Post by **JJ240** » Thu Feb 20, 2003 8:21 pm

Questions are great...because you know if youve got it theres more people who want to know but havent asked. Its great to see more IA people here need to have a midwest 240 meet ATL is a long drive

Post by **96_S14_SE** » Thu Feb 20, 2003 8:21 pm

PSI240 used to run a coustom one on his 11 sec KA24DET.

From the images it looks like a stock mani, hacked off about 8 inches down the line, each runner welded to a 1/8" - 1/4" wall aluminum tube that is 3" or more in diameter with a plate welded to one side and the TB bolted to the other. Then It looks as if some vaccume nipples were added and probably tacked the iacv somewhere in there. Seriously doubt he bothered with the egr hehe.

That a future planned mod of mine done in the same fashion. Its eaither that or cut the runners closer to the flange, and make up the space using aluminum tubing. That way I could easilly port the remaining section out.

Should be rather simple as all I would need is aluminum stock, a spare mani to hack, and a tank of argon (have everything for AL but the argon as I weld mostly steel with its own cabling / wire and argon/co2, and rent out a tank when doing aluminum.)...

Dont know how much of a gain would arise but its not like itll cost a whole lot to do this way. It would probably cost more for the spare mani or argon rental then the AL stock...

Post by **96_S14_SE** » Thu Feb 20, 2003 8:21 pm

Hmmm just a thought, but since the vh45de (q45) TB is larger then ours and it will be a coustom manifold, I may have to source one of those when the time comes...

Ahhh now time to search on decent sized tb's with both size cost and avil in mind.... I guess thats the joy of diy jobs...

Post by **Aries** » Thu Feb 20, 2003 8:21 pm

if anyone is TRUELY interrested in a custom manifold, I could probably be pusruaded to build a large plane with 8 inch runners similar to Honda's Skunk II series of manifolds.

Sheet metal intake manifolds have proven to create more torque, and widen the powerband on almost every motor tested on.

Anyone interrested?

Post by **Scott McLellan** » Thu Feb 20, 2003 8:21 pm

What kind of price are we talking about here, Aries?

Post by **Aries** » Thu Feb 20, 2003 8:21 pm

not sure.I was just wondering if anyone would even be interrested in the possible gains before I go building one.

It would definately be avainlable to the NICO crowd at a discount though

Post by **sethulrich** » Thu Feb 20, 2003 8:21 pm

I'd be interested at some point in the future (I can't afford anything right now). But I'd wanna know what kinda gains it makes before getting one. Also...I'd like to pass emissions....i.e. keep egr. (but I donno anything abt passing emissions. Do u need egr to pass emissions? Basically tho, I would want everything that hooks up to the stock manifold to be able to connect to the new one. Hope that's not asking too much, hehe! But, since I can't afford it yet anyway, don't worry too much about what I want.

Post by **sultan** » Thu Feb 20, 2003 8:21 pm

want to make one for my car? i'm too poor to pay but i'll give you a spare intake plenum and throttle body, better yet use the spare tb to make it a 2 tb setup, both 85mm! it's not a KA, of course.

Post by **96_S14_SE** » Thu Feb 20, 2003 8:21 pm

Aries wrote:not sure.I was just wondering if anyone would even be interrested in the possible gains before I go building one.

It would definately be avainlable to the NICO crowd at a discount though

What are about the average gains by adding a SM intake to an NA 4 banger on the average...? Im seriously considering making a design simillar to jays (psi240) mani at the shop. Spent most of the day pricing raw aluminum stock and the avg price of used mani's to hack up hehe.

I was planning on going "junking" at my fav yards to see what kind of new stock they may have gotten tommorow. Ill probably go there, and call a metal warehouse to see if I can get a better deal on the stock. Since my friends gf is out of town I am going to see if I can get these parts, then get some shop time in as my mig resides there.

Any idea what would be a decent dia of tube to use for the new section the choped and ported oem runners connect to (actual name I cant think of right now)? I was thinking 3" ID but I think the q45 tb is what 80mm? So I may need to go larger.... just in case.

SO if you are familliar with jays setup any aproximation on possible HP increase? If I only get 5 hp it would still be benificail and one of my cheapest $/hp ratio mods to date hehe. Last time I got excited over a diy project was when I replicated the Nismo power bar, for 13$ including paint, and got the parts, made it, and installed it only after seeing it 8 hrs previous to that

I dont think Ill be an STS solo II car anymore though..... hmmm desicions decisions...

Post by **Aries** » Thu Feb 20, 2003 8:21 pm

typically the gains seen are in the neighborhood of 3% hp and 9-13% tq. Please remember, these are percentages, so more mods will net you a larger gain...

I was thinking about using a ported VG35 throttle body on a 4 inch diameter plenum with 8-10 inch runners to the intake ports on the head. No stock manifold parts would be used, and this would be a dirrect bolt in replacement.

This should allow for a maximum flow rate of 1000 cfm on a gasket matched head with a 5 angle valve job, and blended bowls.That is way more than enough flow for even the highest boosting turbo KA's arround to stay constant with airflow.

To compensate the added airflow, there will be certain steps necesary. Fuel pressure will need to be bumped by 5-7 psi, and the stock regulator replace with an aftermarket one. Intake tubing would need to be much shorter, and the battery re-located as the MAF placement would need to be 12-14 inches from the throttle body for maximum flow consistancies without reverse flow in the tubing. I would also go ahead and upgrade to a Cobra Mass Air and have the computer tuned accordingly for the new mass air and throttle body.

This mod would not be one for the average user just looking for a couple quick horses. Sheet metal intakes are used in professional race cars for a reason. THEY WORK. You do all the tuning for them, and the car makes a ton of extra power. If not, you may have a problem even keeping it running at idle.

Post by **96_S14_SE** » Thu Feb 20, 2003 8:21 pm

I would do it out of all SM but I dont like the idea of having to fabricate new injector mounts, and the likes. Also the water outlet is in this piece as well.

I assume by using the vq35 (as their isnt a vg35) TB it would be out of what, the pathfinder? I know the Z and G35, max and alti all use electronic or fly by wire TB's and converting them wouldnt be too cost effective hehe.

Since it will be a sheetmetal intake why not use some other type (possibly dare I say it?) like some sort of domestic TB as they can be had cheaper then a newly released nissan type.

Post by **Syntax360** » Thu Feb 20, 2003 8:21 pm

i'd b interested...it would be nice if u could list a price, but it's cool

Post by **Aries** » Thu Feb 20, 2003 8:21 pm

Yes, the TB would be out of a Pathfinder.I have actually thought about using an LS1 throttle body in the 72mm size, but decided against it as the throttle body would in the long run on a modified motor flow better than the KA Head is capable of, and would result in turbulence in the plenum, and lost power.

I'll get price estimates up as soon as we have one together and on our shop car.

Post by **S13Ka24e** » Thu Feb 20, 2003 8:21 pm

If it would fit the ka24e I might be interested.

Post by **Aries** » Thu Feb 20, 2003 8:21 pm

This will be able to fit on either KA24DE or KA24E.

Post by **SPIRO** » Thu Feb 20, 2003 8:21 pm

I am DEFINATELY interested. For my SOHC of course

Post by **zeardux** » Thu Feb 20, 2003 8:21 pm

i would be very interested if it can fit a sohc and hold up under boost.

Post by **SSS** » Thu Feb 20, 2003 8:21 pm

Has anyone considered a twin TB setup?

Post by **96_S14_SE** » Thu Feb 20, 2003 8:21 pm

I did, and also toy'd with the fact of progressive TB's (saw a 13b tb the other day that had 3 openings and it looked rather sweet, I just dont know how much itll flow as I gotta mic one).

I am putting mine off till I go FI due soley to the fact I want to stay in my current class for scca.. Once the turbo goes in Im bumped up so practically anything goes

By then I should have a solid design worked up anyway..

Post by **nismostreetracer** » Thu Feb 20, 2003 8:21 pm

I would be interested. I'll look for a used manifold in the meantime.

new intake mainifold

new intake mainifold

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