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Engine Modified intake manifold and throttle body

Discussion in 'Powertrain' started by DriftinRolla, Aug 23, 2004.

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    DriftinRolla Guest

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    Modified intake manifold and throttle body

    Made a few changes to the throttle body and intake manifold, check out page 2 of my cardomain page for pictures. Very Noticable gains. I need to raise the fuel pressure, cars running a little lean now according to the A/F ratio gauge.

    Later
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    dominator 04 Rolla 5spd.

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    Cool... I also removed the square lump on the TB's inlet side, smooth bored and polished inlet and outlet side, and smoothed down the butterfly shaft bolts. I also cut down the intake manifold's 2 protruding vaccum fittings, removed all ridges from both ends and down in the 2 outer outlets, enlarged the 4 outlets to match the intake ports, and smoothed and polished the intake ports down to injector lump tip (about 1 1/2" deep) for an amazing improvement...
    Interesting mod on your butterfly shaft, by the way.
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    DriftinRolla Guest

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    I was so happy with the results that I pulled it all apart again to open it up a little more. Thanks for the ideas, I cut out those steps on the intake side and got rid of some more of the butterfly pin, I'll post more pics tonight.

    later
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    polo708 New Member

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    Location:
    9thgencorolla.com
    has anyone dried the DIY on rainmakers cardomain DIY page? The one where he removes the coolant something from the throttlebody? He said its a pretty noticable gain
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    wi rolla Guest

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    I have done it, but im not sureif it did anything or not. When I ran my 15.897 all I had for performance(HP) mods was SRI, Axle-Back, and TB Coolant Bypass. Give it a try, there's really nothing to loose.
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    dominator 04 Rolla 5spd.

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    Ya, I also did the TB coolant bypass with a simple piece of 3/8" OD copper tubing. I did all my intake mods in one shot. I've had no problems with it and a CAI down to -50* F.
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    rolla_dink Guest

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    it just keeps the throttle body from heating up, adding more heat especially with the S/C. It is noticeable after the car is running hot.
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    Schoat333 New Member

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    so whaen you guys pulled the intake off did you have to get a new intake gasket or was it reusable?
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    APC_MATRIX_ Guest

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    It should be reusable for a couple times since our cars are pretty new still.


    BTW, great mods there guys :twisted:
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    DriftinRolla Guest

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    you can reuse it with no problem.

    later
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    wi rolla Guest

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    anybody care to make us a DIY?? Or is this pretty easy?
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    DriftinRolla Guest

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    Its fairly difficult, you need a pretty large assortment of air tools. The amount of metal I removed would be next to impossible to take out by hand. Best thing I can recommend is to pull off the intake and throttle body, and take a look at it, you can see al kind of restrictions, you can be as mild or as wild as you want, any little bit helps.

    later
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    Schoat333 New Member

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    yea it is fairly dificult... i decided to get out the rotory tools today and give this a shot... i ground the idle air port and the vacuum port smooth on the inlet side... took a lil bit and i took off alot of metal. then i smoothed the ridge that goes all the way around by the butterfly valve smooth (that is what its called right?). and then i smoothed it all the way to the edge to make it a nice smooth surface all the way to the butterfly valve. i ground the two vacuum ports that stick thru into the intake right behind the throttle body off so they were smooth with the intake.. plastic gotta love it. and then i opened the intake runners up a lil bit to match the cylinder head intake ports. took me about 3 hours to do it all. i was taking my time smoothing the throttle body to get it just right.

    question for those other that did this... how far down into the intake runners did you open up to match the head?
    i only went a half inch or so and just angled it to meet the size of the head ports and the size of the runners.
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    dominator 04 Rolla 5spd.

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    I tapered in about an inch deep. With my rotary tool, flexible extension and coarse flap wheel, I also removed ridges from down in the 2 outer runners (pretty sure it was the outers and not the inners) and all ridges in the inlet. I also had to drill out the 2 vaccum ports's tips to re-open the hole after trimming them down...
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    wi rolla Guest

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    so, how big of a difference is there, i was thinkin on just doing my throttle body....
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    dominator 04 Rolla 5spd.

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    There was a great difference doing all the TB (+coolant bypass), intake manifold and the intake ports. Power gain was greater than with the CAI. Low end torque is improved as intake air velocity is increased, causing the powerband to start at a lower RPM, while improving high RPM breathability...and the sound note 8) .
    I used a drum sander kit (cylindrical sandpaper on rubber 'drum') to bore both ends of the TB. I then perfected the transitions with rotary tool, and polished it to a gleam with gradually finer sandpaper, then metal polish. Doing just the TB will give just a bit of a gain. Typically, I hear it'd give you about 2 or 3 ponies.
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    totoryan Guest

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    tb

    does anyone has a diy for tb works????
    and do you need to replace the pistons after doing the tb ????
    thanks!!!



    (((( tb works and intake works))))
    headers where can i buy it???? i live in sf ca
    thanks again
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    APC_MATRIX_ Guest

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    Re: tb

    No you don't need new pistons after doing this mod and you can get a very good header from JP performance, best one IMO.

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