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[Eggylshatch]

OBX ITB setup... price is nice, but looking at the pictures it wasn't making much sense... I think either the tard selling it assembled it wrong for the pictures, or OBX has done some interesting engineering.  Look at the injector locations in comparison to the throttle bodies

http://cgi.ebay.com/ebaymotors/OBX-Individual-Throttle-Body-ITB-Acura-Integra-GSR-NEW_W0QQcmdZViewItemQQhashZitem5637a393e4QQitemZ370300654564QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

[Doug]

OBX has done some interesting engineering

Now that shit makes no sense

[Avistar23]

i saw some k20 ITB's setup just like that, and upon research found this

Whats wrong with the injector location?

You can put the injector before or after the butterfly. Look at an F1 motor. Most of them have the injector before the butterfly.

[t_cel_t]

im pretty sure they are called stand off injectors

[t_cel_t]

Stand off injectors

[shogun]

is it me or the number 3 cylinder looked like a lot less fuel, there was a circuit car here that used that type of injection but had injectors really far away from the throttle platesi believe it was a kinsler injection

[Urban Indian]

is it me or the number 3 cylinder looked like a lot less fuel, there was a circuit car here that used that type of injection but had injectors really far away from the throttle platesi believe it was a kinsler injection

I was noticing the same thing

[Eggylshatch]

I see it working there, just failing to understand how it works with the throttle closed at idle.  I know some air still goes through, but it would just seem like fuel would hit the throttle plate and puddle there?  Egay pwned me.

[widebody93]

is it me or the number 3 cylinder looked like a lot less fuel, there was a circuit car here that used that type of injection but had injectors really far away from the throttle platesi believe it was a kinsler injection

camera angle 

[HiProfile]

Yeah, probably poor lighting & poor camera.

I was looking at some bikes lately, and found a few with some injectors that stand way the fuck out. Speaking of bikes, a bunch of bike ITB's have them in that spot. Then if you step back 2 decades, you'll find TBI systems are somewhat similar. THEN you may recall the DPFI system on EF's, where I'm very sure one injector is above the throttle plate.

Stand off injectors follow the idea that injectors need to be placed much farther from the valve vs carbs to get the same atomization. That only matters when you inject huge amounts of liquid in relative to valve size. Since each intake stroke will suck in more than that full column of air, it will still work at idle where it's 99% closed.

[d112crzy]

I wonder how these will do compared to a performer x. I know the H22 obx itb's did surprisingly well.

[widebody93]

I wonder how these will do compared to a performer x. I know the H22 obx itb's did surprisingly well.

Not compared to a small ass turbo smothering the motor.... ITB's are cool and all "I like the sound" but never witnessed one that rocked or impressed oved a S2 manifold with upgraded T.b.

[junkyard racer]

i had these itbs. i went into detail with them on gay-tech. search.

[Adam Lofton]

im pretty sure they are called stand off injectors

In the power-sports industry that configuration is known as a shower-head injection set-up. That is common on all late model Japanese production race bikes, many Ducatis, Aprilia and I would suspect Triumph is going to follow suit.

Most Japanese bikes having a before (throttle valve) and after set up in which the secondaries are arranged in the top half of the air box pointing to the velocity stacks and the primaries are in the port runners as close to the valve as they can get them.

I see nothing wrong with that OBX set-up per se. I wouldn't want to be responsible for tuning them though.

[SgtB]

Better atomization = less HP blown out the exhaust. Sick.
http://www.youtube.com/watch?v=m27xXVgg1nc&feature=related

[1slow91hf]

i dont think there would be much of an issue tuning them since its a single TPS with direct driven single linkage butterflies with minimal adjustment

[junkyard racer]

to my knowledge, no one has "properly tuned" the set I had. 

[SgtB]

i dont think there would be much of an issue tuning them since its a single TPS with direct driven single linkage butterflies with minimal adjustment

They're pretty temperamental, and usually need a tweak every time the seasons change. They can be tuned quite well if done properly though. Getting the linkages all equal between the butterflies can be a nightmare though.

[Joseph Davis]

It is, it's just synching carbs all over again.  Not a nightmare if you've got an IQ of five and a synch tool.

[SgtB]

if you've got an IQ of five...

Fuck.

[Joseph Davis]

They even make multi-runner synch tools for the sort of mentality that gets impatient with using one tool on four runners, costs under $100 IIRC.

[SgtB]

Just had the realization that , other than lawn equipment, I've never tuned a carb, or rebuilt one. My first car had a single throttle body injector. Everything I've ever touched has been EFI. I need to study.

[Joseph Davis]

Go hang out with some old men who own British sportscars, they will instruct you in the fine art of syncing side draft carbs, and what to use instead of straight SAE 30 in their carb dampers.

[snm95ls]

Atomization...




Synching throttle plates is hard?

[SgtB]

No.

[Adam Lofton]

I use the latest synchronization tool from motion pro called the SyncPro. It uses non-toxic manometer fluid instead of mercury. It is finicky but accurate as fuck.

[SgtB]

Ahh. That picture answers all my questions. Makes perfect sense now.