30 dollar Intake Manifold

[neverlift]

its good they are virgins man, way more a$$ and tittie$ and big booty bishez.

not trying to rush man. I can wait it out. Get yours done first, work on mine in free free time. I know there isn't much of it these day. I'll rock it and brag bout the **** too!

[mmm240]

so pants: how the production of the manifold coming?

[DjPantsSpecR]

pretty much on halt, as school just kept getting worse and worse and worse. Now its finals, i have one tomorrow one friday, and then only one more, then all my free time goes into a few places.

A lot of my time has to go into the FSAE car at school. if we dont have the frame done by winter break we're ****ed. i also have to finish my pedal box, but ive just designed it, i think you would be proud.

so enough of the bull****.

there is a shop that is just opening up north of me. it seems like its going to be run by a pretty young kid, but he personally worked with Ivan, and ive seen a one off supra manifold he fabricated. it was most impressive.

he's been TIGing aluminum for a while now, and he has way more of a capacity to do this than me. He wants to produce an N/A manifold and so do I.

so pending i dont get ****ed over, i might actually work with this guy.

differences in design im considering:

cut the runners just after the injector bosses. this would allow you to run an entirely straight set of runners. from the ricardo wave analysis ive seen of our university car's intake manifold, it makes a noticable difference in high end power if you have a curved plenum rather than curved runners.

so a straight shot for the runners could be added. the reason to not make a new manifold entirely is because it would be expensive to mill out the plate to bolt to the head and water jacket, and still keep the weird inlet port shape. its also not that fun to weld in injector bungs.

circular runners would make the adapter plate to the plenum that much easier to make. plus it could allow for the use of velocity stacks. we've made a nice set out of aluminum for the FSAE car, and its possibly something i could incorporate, if i do infact see that a radiused lip isnt the same effect as a stack.

i know for a fact that with this small plenum volume, filling air to the first and fourth stacks will become a problem. however, plenum design can always change.

well, of course, plenum design has changed.... a member on the team here has done a lot of carbon fiber work. our plenum is currently being made of carbon fiber, so i've included this as a possible way to make a plenum. it would raise cost slightly, but it's weight, heat, adn sexiness can't be beat.

otherwise, with the shop ive talked to, we would probably make it out of half a round peice and then triangle it down with aluminum, similar to my sheetmetal one. this would be entirely welded instead of being a bolt on plenum.

i'll also probably have to add adapter plate milled out of aluminum to accept he throttle bodies, and i rpobably need to come up with a better throttle cable system.

so it could really turn up as a lot of different things. i should do this simplest welded one, just to get some plenums out there. possibly use the straight runner design, radiused air inlets and a welded plenum. this should be more than sufficient.

it doesnt need to be too complicated, and thats the key. my craptastic JB weld and sheetmetal one gave me at least 10-15 wheel horsepower. it has been proven that a 3inch on an N/A KA with no supporting mods can net about an extra 12 wheel horsepower. there is no doubt in my mind, and both me and Ajax's butt dyno, that the intake manifold add's more power than that exhaust. i miss it.

so i guess time is the enemy.

[Bigvinnie]

and this is my BigVinnie style shot... looks just like ya vin

LOL Pretty similar. Good shout out. Anyways the progress looks good. But inorder for the system to be fully functional you need to keep in mind the IACV needs to run in conjunction. Taking a quick glance I couldn't see it mounted anywhere. IMO as long as you are using the stock ecu so you don't run into flow issues it would be nice to see use of all the stock parts bolted to it as well. I know a lot of people think it's just all worthless crap and to help with smog, but all that stuff serves with basic function. I did see the brake booster line being used though, but thats just common sense...LOL On the other hand who cares about the EGR/BPT system, unless you have a cali ecu throwing codes 32 it may cause more problems for the mani than it's worth.Lookin good man, now all you need is an Lincln Electric ARC welder and use some gas to prevent bird droppings, stop using the J.B!!!!!BTW what made you go with a tapered plenum design over abarrel design? MOst NA tuners choose to use a straight barrel for the plenum along with velocity rings used before each runner. What makes the tapered more effective IYO?


Modified by Bigvinnie at 5:47 PM 12/13/2006

[DjPantsSpecR]

lol, the JB weld was obviously for test mock-ups, and its not uncommon to use adhesives for test manifolds. However, it always fails. The manifold would twist at WOT and crack different places with time. i ran this for three weeks and repaired it once a week. the third time it didnt fail, but i had already removed it back for stock for school.

incorporating the IACV and the AAC is pretty easy to pull off, it just requires plumbing an additional hole in the plenum.

however, i havent used my IACV of AAC in over a year now with no problems until winter. i also have the butterflies and all water lines removed, so in the winter getting it to idle as it gets closer and closer to zero is hard. otherwise, my car idles great, although i agree, i'd rather have this stuff tuned out, rather then having it bandaged.

tapered plenum is for several reasons: its the easiest way to make a full size plenum 50% of its current volume. n/a motors want a smaller plenum volume for high rpm power and throttle response.

i've also seen some computer CFD showing that box type manifolds flow air in this tapered stream to the forth runner. there is a "bubble" of air circulating in the back corner of a box-type manifold. so i just eliminate the useless turbulence and introduce the air at the same angle to all of the runners.

the angled entry also flows air into the first runner much better, especially because the plenum size puts the first runner so close to the entry. angling the TB 30-45 degrees closer to the first runner helps bring turblence down a lot.

i couldnt really put velocity stacks into this plenum, because they would probably contact the plenum on the 3rd and 4th runners. there would be serious lean issues unfortunately.

i have an arc welder. i jsut didnt think i could arc weld aluminum

[neverlift]

I still have not found time to start mine yet. I have a few thoughts put together for it,but the wife and kid take all my time.

[DjPantsSpecR]

i just put down the last calc final i'll ever have to take, then one more tomorrow, and then one more next week then i have one month to complete as many projects as i can.

wouldn't that be sweet to just have a month to you and your car? it might be in below zero temp's but i usually have little space heaters right under the hood with me.

I have superchargeing in my eyes now. i wanna see the feasability of an M90 mounted around where the stock AC was. i'm looking into it.

but for this winter i should complete at least 1-2 manifolds, as well as a high compression build for myself. i might be able to afford a daughter-board now too, but i dont know where to get the best quality for a reasonable price.

so, i need to get to work clearly

[Bigvinnie]

l

tapered plenum is for several reasons: its the easiest way to make a full size plenum 50% of its current volume. n/a motors want a smaller plenum volume for high rpm power and throttle response.

i've also seen some computer CFD showing that box type manifolds flow air in this tapered stream to the forth runner. there is a "bubble" of air circulating in the back corner of a box-type manifold. so i just eliminate the useless turbulence and introduce the air at the same angle to all of the runners.

the angled entry also flows air into the first runner much better, especially because the plenum size puts the first runner so close to the entry. angling the TB 30-45 degrees closer to the first runner helps bring turblence down a lot.

i couldnt really put velocity stacks into this plenum, because they would probably contact the plenum on the 3rd and 4th runners. there would be serious lean issues unfortunately.

i have an arc welder. i jsut didnt think i could arc weld aluminum

Good explanation, but that isn't the same flow pattern at lower rpms. A full out barrel style allows each cylinder at lower RPM to grab atmospheric pressure even when the butterfly isn't open more than at idle, this only causes minor turbulence issues if the barrel is proportioned to it's correct diameter, if not then you start to get backfire and popping. This would allow for a much even combustion across all 4 cylinders when RPM and CFM are low below 3000RPM. This would actually raise low end torque, and it wouldn't effect high end response either since as you say it delivers a tapered stream already, which is only created by it's own vacuum. As far as streetability it has always been common to use a barrel shaped plenum, almost every car manufacturer uses that basic characteristic. In all this conception you should just make it as simple as the plenum design of the KA24e , or the FJ20e, I think that is where you will find a good margin of power. The KA24e had almost every flawless characteristic to it's manifold accept for the fact that it used SCV's in every engine model, and it literally hinders high RPM HP...

[neverlift]

thread ninja

dj whats what about high c/r lmk about the high part,I'm wondering how high it can go(streetable,pump gas)

[DjPantsSpecR]

well, im on a budget, so obviously its going to be SOHC pistons, and hopefully iron ITM rings.

thats going to be about 11.2:1, which is just barely streetable. its not too hard to keep knock back with retarding timing and 93 octane, but im already trying to get some deals on an SAFC. its not like an SAFC wont still be useful with a daughterboard.

i dun know exactly what you mean by "lmk about the high part" but 11.2: is pretty high for the street. however, people that actually have it will say its jsut fine. Granted they're tuned for it, but celicas have stupidly high compression ratios.

i always wonder how high you can physically take a KA until the piston design can no longer gain compression over the amount that has to be removed for the valves, plug and squish areas. 15:1 is probably around there.

[neverlift]

I was just making a joke about a 15:1 with turbo in the sliders thread and thought to myself a ka that has 15:1,of coarse with all bolt ons and major head porting and full valve/valvetrain upgrade, tuned.

As for the safc get one they are the best "fine tuner" possible. from a piggy back stand point. They are awsome for that slight rich/lean area you may find in the fuel map that is hurting performance/economy. If used properly one could pay for itself in a matter of months.

I was just curious to see if you was trying to bust that envelope open like < those teeth. 11.2:1 is a bit more than what I would trust the gas around here But some octane boost could fix that. Always put some meth in the mix to keep knock/ping down,not too much tho.

[Bigvinnie]

The only problem with an SAFC is that you can't see any MAPS, so in the process you would need to use a wide band to tune as well as a dyno, so that you know that it is making the power needed. I myself don't have time to run to a dyno shop all the time so I use a wide band to try and tune as best as possible, then I go out to make a 1/4 mile time. It seems to be effective, but still it could show for greater improvement.Since I have done tuning on the biki for other 240members I have found it to be the best offered for us OBD1 KA guy's. It's really only $100 more for a wide range of tuning.

[neverlift]

no no he is saying he is going to get both. the safc is just to "fine tune". And he knows damn good and well not to go ****ing with the fueling with no afr monitor. When he gets the board for his de you should help him

[matt4pl]

hmmm when i designed my plenum i went for abiout 2.4L, after having read that on a NA motor you wanted as much volume as possible. oh well.

so heres my big questoin: pros and cons of not running any sort of controlled IAC, just a bolt/screw to keep the throttles cracked open a bit.

btw im running a MS, DIS conversion, open stack itb's, s13 cams, hotshot header, 2.5: catback, no cats, UR pulley, should be completed sometime in january







in the pic i still have the plenum attached, but its gone now. this was when i was running a stock ecu

[DjPantsSpecR]

i know, i even saw you selling that too....

what are the pros and cons of not having an idling system?

well you think the car is going to die ALOT. it never does, but you mihgt think it will.

when you close the throttle the rpm's fall, and then they fall to around where you set the idle, but sometime sit falls to 500 adn then bounces between 500-800 before it settles.

it hardly happens at all on stock cams, or when its warm outside. so really the only pro of IACV and AAC is that you dont have that bouncy idle and you dont have t worry about it dieing.

once you get over that though....

[matt4pl]

i ran the car without IAC when i 1st did the itb's, for a week or two. idled just fine. only thing i noticed is when i let off at a higher rpm it would backfire like mad all the way down. without a cat, it should provide for an interesting show for whoever is behind me, unless i can tune the MS to deal with it

[Bigvinnie]

hmmm when i designed my plenum i went for abiout 2.4L, after having read that on a NA motor you wanted as much volume as possible. oh well.

so heres my big questoin: pros and cons of not running any sort of controlled IAC, just a bolt/screw to keep the throttles cracked open a bit.

btw im running a MS, DIS conversion, open stack itb's, s13 cams, hotshot header, 2.5: catback, no cats, UR pulley, should be completed sometime in

You can use a 2.4 liter plenum. No one said that you couldn't use one. But once the plenum becomes matched to the size of it's displacement then other issues start to come into effect such as swirl and velocity which are key contributors to making power. When I mean making power more on midrange of the power band. A 2.4 liter plenum would serve well for a high rpm and rev track engine.On another note when I brought up the IACV it was for a good reason.......There is little to no manual fine tuning involved!!!!!!! In any circumstance if I wasn't using it, and I did need to use a bolt to hold the butterfly open it would just bring me back to the days of tunning webbers or mikuni's, which is nothing more but a pain in the A$$. IACV's are great for regulating decel as well as idle, it serves it's benefits.
Modified by Bigvinnie at 7:48 PM 12/19/2006