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Discussion Starter #1
So i start working on my manifold on monday and it coming along pretty sweet. The holes were gasket matched and all beveled to give the air smooth transition into the runners. Here are some pics of the progress. Do you guys think i should include a spot for the IAC valve or just run without it? I want the car to idle nicely and not cause and CEL. What do you think?









 

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what throttle body will you be using? FYI use some loctite on those bolt, just to make sure they don't back off.
 

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Is this for an IS300/2jzge OBDII? If so there isn't a IAC port, atleast not that I am aware of.
 

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Looking good Juan. So them the pics of the motor and all the work you've done thus far. +rep
 

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nice. Is your GTE swap going into an IS3 or _ ? Just curious as we have limited IM space with the brake booster nearby..
 

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Discussion Starter #10
as far as throttle body, im going with a 90mm Q45tb. The car comes back from paint on Saturday so i can test fit yet. but i shouldn't have any problems hitting the brake booster. i still have a few solid days in the shop so i hope to get it done and done right. I just don't know if i want to take the time and cut a plate for the IAC valve.
Here are some pics of the throttle body.



 

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I dont know why you are stressing the IAC. Again, is this a usdm or jdm GTE and what car is it going into...or more so, will a Toyota ECU be used?
Nice work thus far!
 

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What car is this for? The IS300 does not have a IAC valve, unlike the Supra.
 

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as far as throttle body, im going with a 90mm Q45tb. The car comes back from paint on Saturday so i can test fit yet. but i shouldn't have any problems hitting the brake booster.
I wouldn't be too sure about that. There is a reason that most of the aftermarket manifolds you see for the IS are tapered in the rear to clear the booster. It make look like it's fitting in there, but the flange is not mating to the lower intake and mani sits too high to clear the hood.


 

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Discussion Starter #15
as far as throttle body, im going with a 90mm Q45tb. The car comes back from paint on Saturday so i can test fit yet. but i shouldn't have any problems hitting the brake booster.
I wouldn't be too sure about that. There is a reason that most of the aftermarket manifolds you see for the IS are tapered in the rear to clear the booster. It make look like it's fitting in there, but the flange is not mating to the lower intake and mani sits too high to clear the hood.


as far as clearing the hood, i don't have to worry about that as i am mating to the lower runners. i come to the conclusion that i will have to tapper the rear of the plenum to make room for the brake booster. But that seems like an easy fix. The manifold will look similar to the one made by some of the high dollar company's at a DIY price.
 

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as far as clearing the hood, i don't have to worry about that as i am mating to the lower runners. i come to the conclusion that i will have to tapper the rear of the plenum to make room for the brake booster. But that seems like an easy fix. The manifold will look similar to the one made by some of the high dollar company's at a DIY price.
Look and perform will be two different things. This is actually the same exact setup that First State Motorsport produces. They use the RMR D plenum and drill here and there to work with the lower runners. I am going to assume that you too are using the RMR plenum as they seem to be the only place to get them. This intake setup works fine, FSM or The Quickness from Supra Forum had the intake setup flowed by Head Games and there was no sign of any air flow change in the design.

Again, can you explain what this setup is for? An IS? SC? GS? You keep on asking about a IAC flange, when people keep saying the IS300 don't have one. Also what engine management will you be using? Converting into a non dbw throttlebody will mean you will lose cruise control and the idling controlled by the stock ECU. I think you should explain or give a little bid more detail on you engine and/or turbo setup.
 

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as far as clearing the hood, i don't have to worry about that as i am mating to the lower runners.
What I meant was that it won't go far enough down to mate to the lower intake because the booster is in the way ;)

The fact that your runners taper towards the center should help this, but I'm not so sure I'm fab up the intake before knowing that it will fit. It was an expensive experiment for me :(
 

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Booster or not it needs to be tappered at the rear in order to keep the air speed up to the rear cylinders.

Im thinking that bolt is just for the dummy fit and you will be using a countersunk one. Good effort, looks good for a DIY budget job.
 

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Discussion Starter #19
Booster or not it needs to be tappered at the rear in order to keep the air speed up to the rear cylinders.

Im thinking that bolt is just for the dummy fit and you will be using a countersunk one. Good effort, looks good for a DIY budget job.
The bolt is just there for fit up. Is coming out once its welded in place. after thinking about it, i am going to tapper the back. I have all the measurements now so i think it should be a perfect fit. More pictures to come later in the week.
 

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Discussion Starter #20
What I meant was that it won't go far enough down to mate to the lower intake because the booster is in the way ;)

The fact that your runners taper towards the center should help this, but I'm not so sure I'm fab up the intake before knowing that it will fit. It was an expensive experiment for me :(
At this point, i have no choice but to make the manifold before i do the swap. i figure it should be a perfect fit once im done with it. worse case i have to buy another set of lower runners if this doesnt work. But keep your fingers crossed measured 10 time and cut once no turning back.
 
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