sx sonic
New member
Well today I did alittle more reworking on my throttle body. I'd previously ground down the throttle plate screws but I decided to make a DIY for a member on here.
Figured I might as well do alil more grinding while I had it out for pics. Mind you I stayed pretty conservative because the throttle bore is intricately machined to allow for Idle air control at lower throttle openings.
You do not want to go too aggresive and grind down a contour that is specifically designed to control idle and have a finky engine. (I played with the throttle plate, opening and closing it while noting which contours would have a strong impact on how the engine would idle.)
If you decide to try this do so at your own risk. also take your time and familirize yourself with all the features so you don't absent mindedly grind down what your not supposed to.
----------------------------------------------------------------------------------------------------------------------------------------------------
The actual removal and installation of the throttle body is very straight forward and will take about 10-15 mins to remove.
The porting will take much longer. With a small selection of metal cutting bits (I used carbide cutters made for steel to great effect) it will take 1-2 hours to do the smooth and blend the bore itself.
Then grinding down the throttle plate screws and throttle shaft if you wish to will consume another hour or 2. It's a tight area and smaller bits are required and its grinding steel instead of aluminum so it's much slower going and requires more diligence to not contact the bore on accident
(my dremel and air compressor both died so I didn't get to rework the throttle shaft or grind down the throttle plate screws as much as desired.. or polish what I had done. :sadbanana
--------------------------------------------------------------------------
Step 1- Remove the boost tube. loosen the clamp at the throttle body and wiggle/pull the tube of and folt it out of the way. (the clamp varies, mine was a 7mm socket, some use a screwdriver)
2- Disconnect the throttle body wire connection
3- Remove the wire loom bracket. Use a 10mm socket to undo the one bolt and then leave the braket hang, you'll move it as neccesary later.
4- Remove the 4 allen bolts for the TB. they're 5mm allens. I used a normal allen wrench with a ball end for working at an angle. I also used slip joint pliers for extra leverage when break the bolts loose and for final tightening.
5- Pull the TB out.
Next is the porting. A small assortment of carbide cutters is ideal for much of the work. Some smaller grinding stones or cutters is very hanfy for working the throttle shaft and the plate screws. Sand paper rolls may come in handy as well as some felt bobs for polishing. (I made do with fine sand paper and scotch brite pads after my dremel failed).
Note the 1st few pics are after already grinding down the throttle plate screws and some polishing. The screws normally stick out a good amount.
Heres the inlet ~2" I.D.
note the lip/ridge at the bottom side of the bore. This is the contour I mentioned earliar. For fear of messing up idle quality I recommend being modest with It and just blending it in some or leaving it alone altogether (It might be ok to grind smooth but IDK and I'd hate for anyone to have to buy a new TB)
Here's the outlet/ manifold side. ~1 3/4" I.D.
Theres some strange contours at the top and bottom of the bore. They didnt appear to have any real purpose so I ground one side flush and smoothly blended the other.
Here's with the throttle locked open with a 10mm socket.
agian note the contour at the top of pic halfway into the bore.
Locking the throttle open is neccesary for working the throttle plate screws and may come in handy for reworking the bore. The screws would normally be noticable with the throttle in this position, but as mentioned I'd already ground them flush.
Different angle
I absent mindly bolted everything up before realizing I hadnt taken after pics. So this is the only finished pic I have.
I'll try to get more and better pics to replace the existing ones in a day or three.
opcorn:
-Tyler
Figured I might as well do alil more grinding while I had it out for pics. Mind you I stayed pretty conservative because the throttle bore is intricately machined to allow for Idle air control at lower throttle openings.
You do not want to go too aggresive and grind down a contour that is specifically designed to control idle and have a finky engine. (I played with the throttle plate, opening and closing it while noting which contours would have a strong impact on how the engine would idle.)
If you decide to try this do so at your own risk. also take your time and familirize yourself with all the features so you don't absent mindedly grind down what your not supposed to.
----------------------------------------------------------------------------------------------------------------------------------------------------
The actual removal and installation of the throttle body is very straight forward and will take about 10-15 mins to remove.
The porting will take much longer. With a small selection of metal cutting bits (I used carbide cutters made for steel to great effect) it will take 1-2 hours to do the smooth and blend the bore itself.
Then grinding down the throttle plate screws and throttle shaft if you wish to will consume another hour or 2. It's a tight area and smaller bits are required and its grinding steel instead of aluminum so it's much slower going and requires more diligence to not contact the bore on accident
(my dremel and air compressor both died so I didn't get to rework the throttle shaft or grind down the throttle plate screws as much as desired.. or polish what I had done. :sadbanana
--------------------------------------------------------------------------
Step 1- Remove the boost tube. loosen the clamp at the throttle body and wiggle/pull the tube of and folt it out of the way. (the clamp varies, mine was a 7mm socket, some use a screwdriver)
2- Disconnect the throttle body wire connection
3- Remove the wire loom bracket. Use a 10mm socket to undo the one bolt and then leave the braket hang, you'll move it as neccesary later.
4- Remove the 4 allen bolts for the TB. they're 5mm allens. I used a normal allen wrench with a ball end for working at an angle. I also used slip joint pliers for extra leverage when break the bolts loose and for final tightening.
5- Pull the TB out.
Next is the porting. A small assortment of carbide cutters is ideal for much of the work. Some smaller grinding stones or cutters is very hanfy for working the throttle shaft and the plate screws. Sand paper rolls may come in handy as well as some felt bobs for polishing. (I made do with fine sand paper and scotch brite pads after my dremel failed).
Note the 1st few pics are after already grinding down the throttle plate screws and some polishing. The screws normally stick out a good amount.
Heres the inlet ~2" I.D.
note the lip/ridge at the bottom side of the bore. This is the contour I mentioned earliar. For fear of messing up idle quality I recommend being modest with It and just blending it in some or leaving it alone altogether (It might be ok to grind smooth but IDK and I'd hate for anyone to have to buy a new TB)
Here's the outlet/ manifold side. ~1 3/4" I.D.
Theres some strange contours at the top and bottom of the bore. They didnt appear to have any real purpose so I ground one side flush and smoothly blended the other.
Here's with the throttle locked open with a 10mm socket.
agian note the contour at the top of pic halfway into the bore.
Locking the throttle open is neccesary for working the throttle plate screws and may come in handy for reworking the bore. The screws would normally be noticable with the throttle in this position, but as mentioned I'd already ground them flush.
Different angle
I absent mindly bolted everything up before realizing I hadnt taken after pics
. So this is the only finished pic I have.
I'll try to get more and better pics to replace the existing ones in a day or three.
opcorn:-Tyler
