Intake Manifolds

[jajimo]

Okay, so I have a few questions about Intake Manifolds.

If I want to upgrade an IM, what kind of attributes should I be looking for? What is the main goal a performance IM would be trying to achieve? How is this goal generally met?

I'm trying to get information for an All Motor build up, so that's why I ask.

What's the difference between a stock OE manifold and an ITR manifold? Larger throttle body (is that even considered part of the IM)? Injector placement?

Is it possible to modify an OE manifold to produce the same benefits as an aftermarket one?

Finally, and please don't kick me for asking this. But what are these round things that replace the "traditionally" shaped manifold on the pic below?



(a side note, I was looking at OE replacement manifolds for my Accord, just out of curiousity, no I'm not trying to build up my F22B, but the price was $520, where as I found a Type-R manifold at KingMotorsports for only $300! What's up with that?)

Thanks!

[Ricochet]

Those "round things" are individual throttle bodies, ensuring each cylinder receives the same amount of air unlike a horizontally-mounted manifold where the first one gets more than the last. They are meant for extremely modded engines with wild cam setups and not recommended for stock engines.

If you are looking for a good aftermarket manifold get one that has a larger diameter inlet and has curved surfaces like the Edelbrock (sp?).

[YellowITR479]

I dont know offhand what your manifold looks like but any aftermarket piece will give you a slight gain. The edelbrock is for higher rpm's (dyno's prove it) so unless your spinnin 8000 rpm + and boost, I would go for the skunk2 or comparitable

If you are going for an allmotor setup I would say put on the ITR manifold which is almost identical to the Skunk2 Man. I would def replace he throttlebody with atleast 1 of the same size ID as the manifold. I wouldnt play with the injectors unless you got a serious all motor setup in the works...I would get an pressure riser and a fuel rail though. If all motor is your game you might want to look into port matching the manifold and throttlebody, which will also do wonders if you ever decide to put some boost into your life

[YellowITR479]

On a side note.....would it be possible to boost a car with individual throttlebodies like the motor above and get benefits beyond an traditional steup?...i dont see why not

[jajimo]

I figured those were individual throttle bodies, but I wasn't sure. Are they just ran in the open like that, or is there more intake hardware (filter, etc)?

I'm not sure if I'm going to be running a B16 or an H22 yet because it is going to be quite some time before I purchase the engine. I'm going to try to buy a cheap ass D16 first and work on it to familiarize myself with the internals before I spend money on a more expensive engine and risk ruining it. The H22 would be good because I already have an Accord that I'd be able to throw it in once I buy a new daily driver, but the weight is a concern. However, I'm looking to build a particularly high-revving engine (10,000+) so I've heard the B-series will be much better for that. Obviously, I'm looking to build a full-race motor, and I'm going to Japan next summer for several months and hope to pick it up there along with some "goodies" for it.

If the individual throttle bodies are designed for full-race motors, then I'd certainly be interested in those.

[Ricochet]

Originally Posted by YellowITR479

On a side note.....would it be possible to boost a car with individual throttlebodies like the motor above and get benefits beyond an traditional steup?...i dont see why not

No, itb's are meant for all-motor setups only.
Yes they've been modified for boost, but in those setups people had to put a box over all four with one intake tube going into the side of that like a stock one, defeating the whole purpose of them.

[jajimo]

I just looked at the price of a Toda ITB for a B16: $2600. So it'd be more of a long term investment and probably not the first thing I'd throw on it. Doesn't mean I won't eventually though =)

[YellowITR479]

"with one intake tube going into the side of that"

That could easily be avoided by fabricating a intake that joined in the middle.

If you look at the fuel rail and injectors on the picture above you will see that where the fuel rail and injectors used to be would be a place for some kind of intake box....I can tig weld and im pretty sure I could fab something that would work in this situation...not arguing, just my opinion.

[Ricochet]

Go here.
http://www.automotiveforums.com/vbul...hrottle+bodies