2.0 LSJ Engine: SMS Throttle Body
Thread Starter
Domestics Pwn
Joined: 07-17-05
Posts: 1,409
Likes: 1
From: Phoenix AZ
SMS Throttle Body
Well I installed my SMS Throttle Body tonight. It was a pretty easy install so I figured I would do a How-To.
Here's a couple pics of the throttle body
The throttle body looks pretty good. When put side by side you can definitely see where they smoothed out the rough casting, as well as where they enlarged it.
I don't know if it will be good for any significant power gain but what the heck. It was around $300 and you get 150 back when you send in your core
(if you want to send it back, I intend on keeping mine). Well on to the install !
Tools:
Long 1/4 10mm socket
1/4 ratchet
Flathead Screwdriver
First I used the screwdriver to loosen the clamps on the intake pipe going from the TB to the piping going down into the fender. I left the hose that
is connected to the intake pipe on and just moved it out of the way as the pic shows.
The throttle body is held on with 4 10mm bolts, an electrical connector, and a vacuum tube. On the vacuum tube where it connects
to the throttle body you will see where 2 little plastic pieces hook around each other. You simply slide on of the plastic pieces away
from the other and the tube comes off. The pic I took is not the greatest but once you see the tube in person its fairly obvious what you
need to do to remove it.
The electrical connector is a pain in the butt to get to if you try to remove it without unbolting the throttle body. So I removed the 4 10mm
bolts holding the throttle body on so that I could rotate the TB to get better access to the connector. On one side of the connector you will see
a grey plastic insert and a black plastic push tab. I have seen other people refering to this connector saying you have to remove the grey insert
to push the tab down. This is NOT the case. All you have to do is gently slide the grey plastic insert back and you can then push down on t
he black plastic tab to remove the connector. The pic is of the connector with the grey insert pushed back.
Now that everything is disconnected from the TB it comes right out. You "should" replace the TB seal but it is not necessary. Just be sure
that it remains on the supercharger in place as shown in this pic.
Heres a pic of the new and old TBs side by side. You cant really tell much of diff in the pic. My camera is good enough to really show you
the work they have done inside the throttle body. I did measure the 2 and the SMS TB is about 3-4mm larger then the stock unit, it is
also very smooth in comparison the stock unit.
The installation of the new TB is pretty simple. Just reverse the removal steps. When reinstalling the connector just be sure to push
the grey plastic insert back into place. On the vacuum tube going into the throttle body you just need to push it on and it will lock into
place. To be sure its in place you can lightly pull on it and it should not come off. When careful not to over torque the TB bolts as you
are going into aluminum. Make sure you have your intake tube all the way seated on both sides before you tighten the clamps back
down. Make sure you get the clamps fairly tight, I have heard of some members have this tube pop off. Heres a pic of the finished
product. It looks stock as the SMS TB is just a bored stock TB.
Started it up... Everything seems good. I only took for a quick around the block test drive. Throttle response seems slightly improved.
It feels a little bit like the power delivery is smoothed out... but this may just be perception. Ill have to drive it more to be
for sure. Don't know about any power gains either.. I only took it for a really quick test drive and only got on it once. I just wanted
to make sure that the CEL was not going to illuminate and I wasnt going to have any running problems. Overall Im pretty happy...
the porting job seems pretty nice. The mods was fairly cheap at only $150 if you send the core back.
Hopefully this How-To will be helpful !
Here's a couple pics of the throttle body
The throttle body looks pretty good. When put side by side you can definitely see where they smoothed out the rough casting, as well as where they enlarged it.
I don't know if it will be good for any significant power gain but what the heck. It was around $300 and you get 150 back when you send in your core
(if you want to send it back, I intend on keeping mine). Well on to the install !
Tools:
Long 1/4 10mm socket
1/4 ratchet
Flathead Screwdriver
First I used the screwdriver to loosen the clamps on the intake pipe going from the TB to the piping going down into the fender. I left the hose that
is connected to the intake pipe on and just moved it out of the way as the pic shows.
The throttle body is held on with 4 10mm bolts, an electrical connector, and a vacuum tube. On the vacuum tube where it connects
to the throttle body you will see where 2 little plastic pieces hook around each other. You simply slide on of the plastic pieces away
from the other and the tube comes off. The pic I took is not the greatest but once you see the tube in person its fairly obvious what you
need to do to remove it.
The electrical connector is a pain in the butt to get to if you try to remove it without unbolting the throttle body. So I removed the 4 10mm
bolts holding the throttle body on so that I could rotate the TB to get better access to the connector. On one side of the connector you will see
a grey plastic insert and a black plastic push tab. I have seen other people refering to this connector saying you have to remove the grey insert
to push the tab down. This is NOT the case. All you have to do is gently slide the grey plastic insert back and you can then push down on t
he black plastic tab to remove the connector. The pic is of the connector with the grey insert pushed back.
Now that everything is disconnected from the TB it comes right out. You "should" replace the TB seal but it is not necessary. Just be sure
that it remains on the supercharger in place as shown in this pic.
Heres a pic of the new and old TBs side by side. You cant really tell much of diff in the pic. My camera is good enough to really show you
the work they have done inside the throttle body. I did measure the 2 and the SMS TB is about 3-4mm larger then the stock unit, it is
also very smooth in comparison the stock unit.
The installation of the new TB is pretty simple. Just reverse the removal steps. When reinstalling the connector just be sure to push
the grey plastic insert back into place. On the vacuum tube going into the throttle body you just need to push it on and it will lock into
place. To be sure its in place you can lightly pull on it and it should not come off. When careful not to over torque the TB bolts as you
are going into aluminum. Make sure you have your intake tube all the way seated on both sides before you tighten the clamps back
down. Make sure you get the clamps fairly tight, I have heard of some members have this tube pop off. Heres a pic of the finished
product. It looks stock as the SMS TB is just a bored stock TB.
Started it up... Everything seems good. I only took for a quick around the block test drive. Throttle response seems slightly improved.
It feels a little bit like the power delivery is smoothed out... but this may just be perception. Ill have to drive it more to be
for sure. Don't know about any power gains either.. I only took it for a really quick test drive and only got on it once. I just wanted
to make sure that the CEL was not going to illuminate and I wasnt going to have any running problems. Overall Im pretty happy...
the porting job seems pretty nice. The mods was fairly cheap at only $150 if you send the core back.
Hopefully this How-To will be helpful !
Last edited by TommyP; May 19, 2012 at 08:54 PM.
Senior Member
Joined: 04-11-04
Posts: 2,175
Likes: 0
From: patterson, ca
lol tb good for 2hp? lol, on my cavalier its good for 10whp for a 10mm upgrade
i dynoed at 140whp, with i/e/h, people with the same mods plus a 62mm t/b compared to 52 are dynoeing consistantly at 150whp. so a good t/b thats done right and is not just 5mm larger will benefit. more w/ FI.
i dynoed at 140whp, with i/e/h, people with the same mods plus a 62mm t/b compared to 52 are dynoeing consistantly at 150whp. so a good t/b thats done right and is not just 5mm larger will benefit. more w/ FI.
New Member
Joined: 10-17-05
Posts: 71
Likes: 0
From: Walden Ny
Originally Posted by silverSS
^^yah, its not even worth 150 for a 3-5mm increase, if it was 10 like you were saying, im sure i would get one, but the throttle body really cant be bored out much more than 73-74mm i guess
Thread Starter
Domestics Pwn
Joined: 07-17-05
Posts: 1,409
Likes: 1
From: Phoenix AZ
Originally Posted by Conflykt
Nah i'm sure it could, I'll wait for BBK or someone along thos lines to make one that'll give a lil better gain
Banned
Joined: 05-01-05
Posts: 3,628
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From: USA
i doubt it...but idk for sure..im thinking about ordering one for christmas
exhondaman-now that you have had it for a while, how is it running,and does the throttle really feel smoother, or is it a placebo effect?
exhondaman-now that you have had it for a while, how is it running,and does the throttle really feel smoother, or is it a placebo effect?
Thread Starter
Domestics Pwn
Joined: 07-17-05
Posts: 1,409
Likes: 1
From: Phoenix AZ
Originally Posted by silverSS
i doubt it...but idk for sure..im thinking about ordering one for christmas
exhondaman-now that you have had it for a while, how is it running,and does the throttle really feel smoother, or is it a placebo effect?
exhondaman-now that you have had it for a while, how is it running,and does the throttle really feel smoother, or is it a placebo effect?
Senior Member
Joined: 11-15-05
Posts: 2,693
Likes: 0
From: Newton Highlands, Massachusetts
but it will help with other mods like CAI, blower porting, etc.
its a small step in free-ing up some flow on the intake tract, to me it seems worth it with the air the blower wants to take in with smaller pulleys, etc.
its a small step in free-ing up some flow on the intake tract, to me it seems worth it with the air the blower wants to take in with smaller pulleys, etc.
