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ITB setup startup - removed idle stabilizer - ok?

 
Old 01-15-2019, 03:24 AM
  #16  
Gulpilen
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Originally Posted by andy-gts View Post
Does the hood close without any alteration, and there certainly are a lot of hoses,,,,,,,,,,,NOS or OIL CONTROL or methanol injection ??
It closes but not without a hole in it... Lots of hoses but no NOS or methanol injection.




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Old 01-15-2019, 03:41 AM
  #17  
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Originally Posted by drnick View Post
Jonas, very crudely I used a micrometer slid down the itb mouth to measure the throttle plate deflection for initial setup. If the car is not street driven then you may be ok without an ICV? Just set the throttle plates for a fast idle and call it good? I’m not sure what others have done..

My setup courtesy of Alex P uses bmw itbs with the vacuum passages cast in place.
Yes, after consideration I will buy a micrometer. I have Suzuki Hayabusa ITBs.

Originally Posted by Strosek Ultra View Post
There are very many multi-cylinder engines having no ICV out there so why should it not work? The throttle plates have to be synchronized. Set the throttles for good idle when engine has reached operating temperature. The only problem I can see is the idle rpm cold will probably not be the same as when engine is warmed up. Here is how they do it for a bike.
Åke
https://pastframe.wordpress.com/2014...nchronization/
Some additional info.
http://www.compsystems.com.au/index....whole-ls-range
Thanks Åke! I will check these and tune when warm (where I mostly want the ok idle).

Originally Posted by Ducman82 View Post
And where will you get the vacuum for the brake booster? I'd plumb in an IAC. Makes life sooo much easier. Not to mention a standalone computer
Originally Posted by Mongo View Post
Curious, can you fab a manifold or block and distribute air from the ISV equally to all 8 ports after the butterflies as long as there is a 'vacuum' port per each runner?
I got a block with collecting the vaacum today (from underneath each plate) to the brake so maybe I can use the same ports "with a one way airconnector"? Lets see.

/Jonas
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Old 01-15-2019, 10:46 AM
  #18  
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In fact you don’t want any “one way air connectors”. Pulses at each port need to balance some to make the throttle stop adjustment a little less sensitive. Retain the check valve at the brake booster and you’ll be golden. Getting the tip-in response perfect will be your challenge, as you try to get all the throttles to move off their stops at exactly the same time. I’ve done this with a collection of various flow detectors like Uni-Syn, but often end up with a couple vacuum hoses to listen above the throttles as I adjust. It’s tedious but worthwhile.
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Old 01-15-2019, 10:52 AM
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Old 01-15-2019, 12:14 PM
  #20  
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Originally Posted by Gulpilen View Post
It closes but not without a hole in it... Lots of hoses but no NOS or methanol injection.


Beautiful symmetrical lay out.....NICE
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Old 01-15-2019, 03:52 PM
  #21  
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Originally Posted by dr bob View Post
In fact you don’t want any “one way air connectors”. Pulses at each port need to balance some to make the throttle stop adjustment a little less sensitive. Retain the check valve at the brake booster and you’ll be golden. Getting the tip-in response perfect will be your challenge, as you try to get all the throttles to move off their stops at exactly the same time. I’ve done this with a collection of various flow detectors like Uni-Syn, but often end up with a couple vacuum hoses to listen above the throttles as I adjust. It’s tedious but worthwhile.
Thanks, one more thing that can be useful
I think they alreade start moving at the same time but they really need to be aligned. So if I put the ICV near b booster with hose and also a hose from ”after MAF” but before ITBs” it should work ?
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Old 01-15-2019, 03:54 PM
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Originally Posted by andy-gts View Post
Beautiful symmetrical lay out.....NICE
Thanks!
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Old 01-15-2019, 03:56 PM
  #23  
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The IAC needs to be able to pump filtered air into the throttle bodies after the butterflies.
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Old 01-15-2019, 11:54 PM
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Originally Posted by dr bob View Post
In fact you don’t want any “one way air connectors”. Pulses at each port need to balance some to make the throttle stop adjustment a little less sensitive. Retain the check valve at the brake booster and you’ll be golden. Getting the tip-in response perfect will be your challenge, as you try to get all the throttles to move off their stops at exactly the same time. I’ve done this with a collection of various flow detectors like Uni-Syn, but often end up with a couple vacuum hoses to listen above the throttles as I adjust. It’s tedious but worthwhile.
Originally Posted by Gulpilen View Post


Thanks, one more thing that can be useful
I think they alreade start moving at the same time but they really need to be aligned. So if I put the ICV near b booster with hose and also a hose from ”after MAF” but before ITBs” it should work ?
Originally Posted by 928sg View Post
The IAC needs to be able to pump filtered air into the throttle bodies after the butterflies.

Yes to the questions.

Allowing post-MAF air to pass into the "vacuum manifold" will work. The vacuum manifold has a hose from below each throttle, with no restrictions or check valves. It will have the IAC line, and the hose from the brake booster, so all eight cylinders can draw air out of the booster as well as from the IAC. Reminder: 1/4" or 6mm ID individual hoses/fittings will be almost equal the flow available through a 12mm from booster and another from the IAC at the same time. It should work.

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Old 01-16-2019, 04:36 AM
  #25  
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Originally Posted by 928sg View Post
The IAC needs to be able to pump filtered air into the throttle bodies after the butterflies.
Originally Posted by dr bob View Post
Yes to the questions.

Allowing post-MAF air to pass into the "vacuum manifold" will work. The vacuum manifold has a hose from below each throttle, with no restrictions or check valves. It will have the IAC line, and the hose from the brake booster, so all eight cylinders can draw air out of the booster as well as from the IAC. Reminder: 1/4" or 6mm ID individual hoses/fittings will be almost equal the flow available through a 12mm from booster and another from the IAC at the same time. It should work.
Thank you! /Jonas
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