knoxtl

Everyone...

So over the past year I have been making changes to my intake manifold on my 06 TL and have not been very impressed with the results of intake swaps and polishing and boring has to offer on our OEM intake manifold. Luckily i have an answer to this. My uncle owns a shop here in dfw and we are going to be building an all new intake manifold I have 3 engineers working on this project and honestly had no idea i was going to get this kind of support when i just mentioned it to him a few weeks ago. Any input would be appreciated. One of my main questions is which throttle body should we build this for? I was thinking maybe not even an acura TB.

Im headed to his shop for 3 days starting sunday to start this project.

knoxtl

Id like to see Gerzand chime in on this.

Atlas.46

subscribed

Scottwax

I'm in Arlington, be glad to have my car used as a test bed.

knoxtl

I will take pics of our work and get you something as soon as me and the mad scientists get together and rip this thing apart.

yungone501

iTrader: (4)

90mm LS7 DBW throttle body FTW!

knoxtl

^^^ Oh yah?? I will do some research today.

bouncer07

So in that past year you made the changes, were they ever dyno'd or were they just butt feels? If you have knowledge of how this engine operates and all of how Honda's vtec works, follow the short runner designs on these intake manifold. You'll get the gains you want. Since this engine is all about low- mid range power, move the power to be used up higher in the RPM would be great and use the low rpms for Daily Drive use. But then again, you guys are just playing with something that won't ever get your money's worth in R&D. Reason is because you'll need Flashpro to funtion this mod and to really get any power out of it. Might as well make a 3.5 - 4.0 intake TB. As of course, off-road use only.

justnspace

iTrader: (1)

if we're already border lining 80mm, why not go to the LS2 90mm!?!??!

knoxtl

I have not dyno'd but have been following others on their mods and swaps. Im not spending a dime on this. Im getting hooked up for free because its family. And i have flashpro. Im not half assing any part of this build.

knoxtl

Justin that TB looks awesome. ^^

bouncer07

What material is this peice being made out of?

You'll need some cams to go that big.

Vlad_Type_S

iTrader: (3)

sub'd

Is it true that long narrow runners produce better lower end torque due to the increased air velocity vs a large open plenum producing better power at high RPMs due to the volume of air available?

knoxtl

Stainless steel tubing^ Not sure Vlad, Im leaving that stuff up to my uncle. I will know allot more after sunday.

knoxtl

Im going to get Bisimoto stage 2 cams

FamilyGuy

If you're going to build something for a non-OEM TB, I think you'll lose a lot of sales opportunities, unless you offer a kit solution, TB included, that works fine with no CEL untuned.

You're better off with an IM that can work with the OEM TB, aim at a bored OEM TB's diameter for max opportunity (for the IM's TB port), with enough material for boring above that, for those running 3.7L TBs. So you'll need 2 solutions, one for base models one for Type S, unless you choose to support only one model (or unless its same TB for both, I don't know that part). Beyond that, you want to offer an IM / TB solution type package. Include matched gaskets and PnP service options on the lower's ports and IM port. Just my opinion.

Design wise, look at Gerzand's dual TB designed IM. It's his design, so work out a deal with him, but it would be awesome to offer something like that, TBs included, if possible untuned with OEM ECU, or shit, in this case, it would be worth it if a tune and flashpro was needed, so long as the gains were there to justify the cost.

Just remember, at some point, too big will be bad and lose power, without other supporting mods, i.e. proper size CAI, cams, head work, etc. Talk to your engineers and Gerzand, and find the sweet spot

Also...be sure to compare against off the shelf solutions, such as OEM (no mods), 3.7L IM swap and PnP OEM IMs.

Also, someone mentioned this beeing a low-mid power engine? I'm not an expert, but to me this is a high RPM horsepower engine, not low-mid RPM torque engine...I would aim for mid-high RPM power, inline with OEM cams/heads, especially under vtec. This is where our engines shine IMO. Why kill that? Support it instead.

Last but not least, don't forget to consider materials, weight, finish and color options.

350

iTrader: (4)

FAST 102MM...but I don't know if the Honda DBW stuff would be able to swap over.

yungone501

iTrader: (4)

Here's the thing with most GM LS series throttle body's, they work exactly the same as the j-series in regards to the actuator and the dual TPS's. The difference was either in the actuators internal resistance and/or the TPS sensors resistance pads. Either way, it's easy to work around. Matter of determining what the stock j-series is and just matching it. I plugged one into my j35a8 ECM once before and the ECM would actuate it one time and then nothing. This is more because the resistance was different and the ECM detected it then disabled any further use of the TB. I believe the GM DBW throttle body's range from 75mm to 90mm but that's just what I remember seeing during my research.

Bottom line: IT WILL WORK IF RESISTANCES ARE MODIFIED.

knoxtl

I PM'd you I think i may want that engine and harness. If it is a mt 06

yungone501

iTrader: (4)

PM returned

i_love_cars

iTrader: (1)

If you make an intake manifold large enough to make use of anything even remotely close to a 90mm TB, then your Bisi Stage 2 cam is not going to be even close to big enough.

Honestly to capitalize on that kind of air flow and make good gains, the TL needs better cam tech. Regrinds on the OEM cam just aren't going to cut it.

I would strongly recommend getting in touch with King Motorsports because they have already been working with Megacycle Cams in California on a fully custom cam design for YAWSPORT's SCCA TL on a fully custom j35a8 build, complete with Mahle bottom-end.

justnspace

iTrader: (1)

congrats on selling your TL.

i_love_cars

iTrader: (1)

Sad day. But on the bright side I get a house out of it, so there's that I guess.

Perhaps in a year or two I'll pick up a KBP for my winter car

anx1300c

iTrader: (2)

A quick 0-100 blast in the 135 should suppress the sadness.

kingkong_dav

Do it with tbe stock tb. I need one

vill0169

iTrader: (4)

^or not...


OP, have you considered making the top half but utilizing something like this underneath it?

http://tbmotorworx.com/tb-motorworx/...nifold-flange/

http://tbmotorworx.com/wp-content/ga...old-flange.jpg

just throwing it out there as a lot of people don't even know these parts exist.

knoxtl

^^^ WOW how did you find that? Thats an interesting design...

98vtec

TB runs a J series in his integra. some pretty sweet work done to it. runs 10's all motor.

vill0169

iTrader: (4)

It is an interesting design but hella functional. not too mention, it'd be a great base to construct different IM designs based on customer demand. Build one for a ZDX TB, an LS TB, dual TBs, etc. Or an NA based and FI based design.

I hate cars

It's not a good idea because it flows enough air to support over 500hp. On a TL you would be at full power before the throttlebody was 3/4 of the way open, leaving the last 1/4-1/2 of your pedal travel useless.
It will? I assume you've "modified" the "resistances" and successfully installed it on a TL with good drivability?

As for the rest of this thread, it's not easy like it used to be to make a couple changes to the intake tract and get big gains. Cars leave much less power on the table these days and the manifold in particular is optimized pretty well. It's unlikely you're going to improve upon the factory in every area. I agree with one of the other posters, focus on the mid-high rpm hp and it probably won't hurt lower end power too much.

The manifold isn't that hard to design. Make the plenum larger so you never have to worry about uneven distribution. The runner diameter and length have a direct effect on the rpm where power will begin and end. It needs to work with the heads and cams being used. Maybe a longer runner manifold for stock engines (fully bolted included) and a shorter runner manifold for engines with heads/cam work. To be honest, stock runners with a larger plenum and stock throttle body would work very well with forced induction. The intake tract requirements go way down with forced induction, I made 602rwhp on a 58mm throttlebody. Naturally aspirated you're looking at a 90mm as a starting point for the same power.

I've always had the best luck with an intake that outflows my heads but not drastically. The intake can be flowed just as the heads can be flowed. I highly suggest this. The correct length can be calculated pretty close to optimal right out of the box and with a little dyno time it can be fine tuned.

I would expect this to be popular with the heads/cam cars and not so popular with the stock engines.

98vtec

the plenum size is generally based on the volume of the engine along with other things that are mathematically over my head. a plenum smaller than the engine is just going to choke it every time the engine cycles. To use "volume", as you said, as an effect for equal distribution is just wrong, IMO. plenum shape, runner shape, taper, runner angle...etc all comes into play with the proper design of an intake manifold. there is much more to intake design than throwing volume at it with X long of a intake runner track to the valve.

I have yet to see a "big" throttle hurt anything other than making the throttle touchy. And even then, if the manifold can't utilize the larger throttle, you are wasting your time. IMO, the useage of throttle body size from the factory has a lot to do with reaching a point of diminishing returns and the comfort of the throttle input. a stock engine isnt going to utilize a bigger throttle unless the engine actually wants more air than the stock throttle can provide. a bigger throttle will be much snappier and can be a bit of a pain when you are in traffic with an engine that actually wants it.

a lot of people who design intake manifolds, will use software like solidworks to help simulate air flow and help determine which cylinders are being starved and which are being overfed and make adjustments needed to help create an even flow.

thisaznboi88

iTrader: (7)

make some ITB's and call it a day Screw the IM

I hate cars

This is mostly true. However, the larger the plenum becomes the less critical shape and overall design becomes. Make it large with no other changes and you're going to improve air distribution. We've built cars with individual throttle bodies or 4-8 carbs with one barrel dedicated to each cylinder, no plenum, just getting air staight from the atmosphere and obviously there were no distribution problems at all because the entire earth is your plenum. When the car is mass produced, engineers have a certain volume to work with due to space. If you're designing your own, you use as large of a plenum as you can physically fit and you don't have to worry about distribution.

98vtec

i'll agree to disagree. What you are saying sounds mediocre on paper, but application in the real world is a bit harder to swallow given most cars have a confined space where you wont be able to run a 10L plenum. And even then, you still have to maintain velocity and apply direction for airflow. Just stating "run a larger plenum to equal the distribution" doesnt mean anything to me as the shape of the plenum in order to gain the extra volume WILL come into play.

there is only going to be so much volume the engine will be able to fill before port velocity slows down and you have to use a smaller throttle just to keep velocity up but then sacrifice the engines ability to even fill the manifold and breathe.

ITB does not maintain the same design properties as a plenum design and even then, unequal distribution can occur from cylinder to cylinder pressure differentials. this is why motorcycle techs use a throttle sync in order to balance the idle and intake draw.

I hate cars

Port velocity is determined by the diameter and to a smaller degree the length of the runners. The plenum isn't a big contributor to any sort of tuning effect. It's there to provide equal flow to each runner.

Again, most would agree that velocity stacks such as ITB with just an air filter on each one provides very consistent distribution. Think of this as an infinitely large plenum.

The larger the plenum the less the shape and everything else matters. For someone trying to build something on a low budget without the millions in R&D going larger is a great way to getting better distribution. There are some basic dos and don'ts but larger is almost always better.

You mention velocity but velocity only begins to matter in the runner. The only downside to going too large is throttle response suffers, been there done that.

Larger plenum volume can make more power on its own with distribution aside. Higher velocity air coming through the throttlebody slows down in the larger plenum, packs in, and creates a denser charge.

A larger plenum will reduce the peak velocity, increase the minimum velocity, through the throttlebody but average velocity will remain the same. What this means is a larger plenum can get away with a slightly smaller throttlebody or you can flow a little more air through your existing throttlebody.

Again, the important part is the runners' size and even taper. Bigger plenum size is better all around until it hurts throttle response. Individual throttle bodies with a plenum setup allows a very large plenum without hurting throttle response.

98vtec

i'll just leave this here:

http://www.enginebuildermag.com/2008...-mild-to-wild/
http://www.circletrack.com/enginetec...d_tech_engine/

I am simply saying that you are making a very intricate process of manifold design seem like 2+2=4 when it is not the case.

in the real world, plenum size and shape matters. runner length, diameter, shape, and angle matter. throttle size in conjunction with the manifold design matters pending application. In the real world, we have confined spaces unless you are in a kart.

if you really expect someone to take you seriously when you say "just throw a huge plenum on it and it will equal things out" well I dont know how i or anyone would "discuss" anything with you and get anywhere.

98vtec

also, just to add, not trying to offend anyone but i can typically make sense of a lot of "paper ideas or concepts" but your no plenum is too large concept doesnt make sense to me.

I hate cars

I figured it would come to this. I hope you're not another teacher posing as an engineer.

I've already covered runners and throttlebodies and the downsides of going too large. In fact I was the first to mention that going too large on a throttlebody was bad. I already said that the real tuning and the critical portion of intake design is in the runners. I don't know why you're bringing this up and trying to twist my words. Again, plenum shape matters less and less the larger you go.

What I've said about plenum volume is dead on. More volume means better distribution. Take the TL's plenum, cut it in half, add a spacer and you'll see better distribution and possibly more power. There is room in a TL's engine bay to make it larger, it's already been done.

Plenum design really is pretty simple as long as you follow some basic rules. You're trying to make this part way too complicated. Save it for the runners and even for the runners, the factory has done most of the homework for you. All we're talking about is a slight variation of factory. Since we have this foundation we can predict pretty accurately the outcome of mods to the runners. People port their runners all the time around here. You better run over to those threads and let them know how stupid they are for not using advanced math and modeling programs before porting.

I hate cars

I've proved my "concept" many times on the flow bench and on the dyno. It's not a concept and it's not a paper one at that. I'm sorry it doesn't make sense to you but it works and it works well up until you hurt throttle response.

You're trying to make it sound like I'm saying just throw a large plenum on and F*** the rest of the design which is not at all what I've been saying. The plenum is relatively easy. Go as large as you can reasonably go with an intelligent shape and focus on the runners. Why is it this new group spends more time twisting words instead of having a discussion?

98vtec

You sure are assuming a lot about me. Read the same kind of attitude towards Tony (who apparently doesnt run with "big boys").