2.0 LSJ Engine: Pulley Swap Howto
#1
Moderator Alumni
Thread Starter
Pulley Swap Howto
Ok Here is a quick write up of my experience doing a pulley swap on a Cobalt SS/SC. I went from stock to 3.25.
1)remove all lines going to the blower and throttle body
-Line from the boost soleniod to the boost bypass value
-wires that plug into the sensor on top of the blower
-Line on the blower itself
2) remove the middle black section of air intake and move it outta the way.
3) removed the 4 bolts that hold the throttle body into the blower and move that out of the way
4) removed the main coolant hose that is routed over the blower snout, be careful fluid is coming out so have rags ready. Not a lot but a splash, just hold it upright and make sure it doesn't tip down and start spilling more fluid everywhere.
5) removed the belt from the blower pulley by taking tension off the belt. The tensioner is the pulley behind and under the blower pulley, I just took a wrench wrapped it in a towel and pried it down, I used a flat head screwdriver to get under the belt and slide it off the superchager pulley.
6) remove the cover plate thats over the fuel lines
7) remove the four bolts holding the blower on It should just lift strait out.
8) This involves removing the pulley, follow whatever directions you get with your pulley removal tool or have a machine shop take it off.
*Take a Break* It's been hell getting that pulley off and you need to rest up so you don't make a mistake when your putting on the new pulley, I had a beer or two.
9) This involves putting on the new pulley or in my case pulley hub. Press it on according to the direction with your tool or again have a machine shop do it.
10) Reinstalled everything, install the new pulley ring, and replace the belt, opposite of taking it off
I started up my car and heard a rattle right away, it turned out to be the ring seated a bit more on the hub after it started and I just tightened down the 4 bolts holding on the ring.
Here is a picture of the installed pulley.
1)remove all lines going to the blower and throttle body
-Line from the boost soleniod to the boost bypass value
-wires that plug into the sensor on top of the blower
-Line on the blower itself
2) remove the middle black section of air intake and move it outta the way.
3) removed the 4 bolts that hold the throttle body into the blower and move that out of the way
4) removed the main coolant hose that is routed over the blower snout, be careful fluid is coming out so have rags ready. Not a lot but a splash, just hold it upright and make sure it doesn't tip down and start spilling more fluid everywhere.
5) removed the belt from the blower pulley by taking tension off the belt. The tensioner is the pulley behind and under the blower pulley, I just took a wrench wrapped it in a towel and pried it down, I used a flat head screwdriver to get under the belt and slide it off the superchager pulley.
6) remove the cover plate thats over the fuel lines
7) remove the four bolts holding the blower on It should just lift strait out.
8) This involves removing the pulley, follow whatever directions you get with your pulley removal tool or have a machine shop take it off.
*Take a Break* It's been hell getting that pulley off and you need to rest up so you don't make a mistake when your putting on the new pulley, I had a beer or two.
9) This involves putting on the new pulley or in my case pulley hub. Press it on according to the direction with your tool or again have a machine shop do it.
10) Reinstalled everything, install the new pulley ring, and replace the belt, opposite of taking it off
I started up my car and heard a rattle right away, it turned out to be the ring seated a bit more on the hub after it started and I just tightened down the 4 bolts holding on the ring.
Here is a picture of the installed pulley.
#7
Senior Member
Originally Posted by Hot Carls R/T
Nice write up....What kinda increased boost levels are you getting? They say 2psi more...How much more power? Seat of the pants of course....Colin
#12
Originally Posted by skoshi130
I know you probably mentioned this beore what mods are done to the car and is there anyting else that needs to be done prior to install
Don't quote me on this but I think he went with colder plugs too rather than stock. At least I hope he did
#13
New Member
Join Date: 04-16-05
Location: Treasure Coast, Florida
Posts: 88
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by zinner
Ok Here is a quick write up of my experience doing a pulley swap on a Cobalt SS/SC. I went from stock to 3.25.
1)remove all lines going to the blower and throttle body
-Line from the boost soleniod to the boost bypass value
-wires that plug into the sensor on top of the blower
-Line on the blower itself
2) remove the middle black section of air intake and move it outta the way.
3) removed the 4 bolts that hold the throttle body into the blower and move that out of the way
4) removed the main coolant hose that is routed over the blower snout, be careful fluid is coming out so have rags ready. Not a lot but a splash, just hold it upright and make sure it doesn't tip down and start spilling more fluid everywhere.
5) removed the belt from the blower pulley by taking tension off the belt. The tensioner is the pulley behind and under the blower pulley, I just took a wrench wrapped it in a towel and pried it down, I used a flat head screwdriver to get under the belt and slide it off the superchager pulley.
6) remove the cover plate thats over the fuel lines
7) remove the four bolts holding the blower on It should just lift strait out.
8) This involves removing the pulley, follow whatever directions you get with your pulley removal tool or have a machine shop take it off.
*Take a Break* It's been hell getting that pulley off and you need to rest up so you don't make a mistake when your putting on the new pulley, I had a beer or two.
9) This involves putting on the new pulley or in my case pulley hub. Press it on according to the direction with your tool or again have a machine shop do it.
10) Reinstalled everything, install the new pulley ring, and replace the belt, opposite of taking it off
I started up my car and heard a rattle right away, it turned out to be the ring seated a bit more on the hub after it started and I just tightened down the 4 bolts holding on the ring.
Here is a picture of the installed pulley.
1)remove all lines going to the blower and throttle body
-Line from the boost soleniod to the boost bypass value
-wires that plug into the sensor on top of the blower
-Line on the blower itself
2) remove the middle black section of air intake and move it outta the way.
3) removed the 4 bolts that hold the throttle body into the blower and move that out of the way
4) removed the main coolant hose that is routed over the blower snout, be careful fluid is coming out so have rags ready. Not a lot but a splash, just hold it upright and make sure it doesn't tip down and start spilling more fluid everywhere.
5) removed the belt from the blower pulley by taking tension off the belt. The tensioner is the pulley behind and under the blower pulley, I just took a wrench wrapped it in a towel and pried it down, I used a flat head screwdriver to get under the belt and slide it off the superchager pulley.
6) remove the cover plate thats over the fuel lines
7) remove the four bolts holding the blower on It should just lift strait out.
8) This involves removing the pulley, follow whatever directions you get with your pulley removal tool or have a machine shop take it off.
*Take a Break* It's been hell getting that pulley off and you need to rest up so you don't make a mistake when your putting on the new pulley, I had a beer or two.
9) This involves putting on the new pulley or in my case pulley hub. Press it on according to the direction with your tool or again have a machine shop do it.
10) Reinstalled everything, install the new pulley ring, and replace the belt, opposite of taking it off
I started up my car and heard a rattle right away, it turned out to be the ring seated a bit more on the hub after it started and I just tightened down the 4 bolts holding on the ring.
Here is a picture of the installed pulley.
#15
Moderator Alumni
Thread Starter
Well the boost gauge doesn't go any higher than stock (12 psi). I am starting to doubt that it will since it's driven by the computer system. However I noticed that when your at lower RPM's (2.5-3.0k) than you can hit 10 PSI pretty quickly.
I am going to do some data logging and compare it to stock runs. I have a pre dyno but it's 85 bux for every dyno run so I doubt I will be having it dyno'd anytime soon.
As far as butt dyno the car seems faster to me I have that working with the boost bypass mod that maven clued me into and so far no codes or limp mode.
I am going to get a mechanical boost gauge and hook it up so I can get some real honest readings and not via a MAP sensor which might not even be calibrated to go above 12.5psi.
I am going to do some data logging and compare it to stock runs. I have a pre dyno but it's 85 bux for every dyno run so I doubt I will be having it dyno'd anytime soon.
As far as butt dyno the car seems faster to me I have that working with the boost bypass mod that maven clued me into and so far no codes or limp mode.
I am going to get a mechanical boost gauge and hook it up so I can get some real honest readings and not via a MAP sensor which might not even be calibrated to go above 12.5psi.
#16
Originally Posted by zinner
Well the boost gauge doesn't go any higher than stock (12 psi). I am starting to doubt that it will since it's driven by the computer system. However I noticed that when your at lower RPM's (2.5-3.0k) than you can hit 10 PSI pretty quickly.
I am going to do some data logging and compare it to stock runs. I have a pre dyno but it's 85 bux for every dyno run so I doubt I will be having it dyno'd anytime soon.
As far as butt dyno the car seems faster to me I have that working with the boost bypass mod that maven clued me into and so far no codes or limp mode.
I am going to get a mechanical boost gauge and hook it up so I can get some real honest readings and not via a MAP sensor which might not even be calibrated to go above 12.5psi.
I am going to do some data logging and compare it to stock runs. I have a pre dyno but it's 85 bux for every dyno run so I doubt I will be having it dyno'd anytime soon.
As far as butt dyno the car seems faster to me I have that working with the boost bypass mod that maven clued me into and so far no codes or limp mode.
I am going to get a mechanical boost gauge and hook it up so I can get some real honest readings and not via a MAP sensor which might not even be calibrated to go above 12.5psi.
#17
Moderator Alumni
Thread Starter
Originally Posted by MarcS
Perhaps switching to a 3 bar MAP sensor would fix the problem?
I dunno much about how the engine management works however I know a LOT of about computers and chances are that the calibration for a stock 2 bar sensor and a 3 bar sensors would be different. So the reads from the sensors would be different.
I would rather have the computer think that the boost is lower than it is so it doesn't trigger any codes. So I am going to just use a mechanical gauge.
In hind sight I would have liked to see what the PSI rating was before I changed the pulley on a mechanical guage....
#18
ByPass Mod
Originally Posted by zinner
Well the boost gauge doesn't go any higher than stock (12 psi). I am starting to doubt that it will since it's driven by the computer system. However I noticed that when your at lower RPM's (2.5-3.0k) than you can hit 10 PSI pretty quickly.
I am going to do some data logging and compare it to stock runs. I have a pre dyno but it's 85 bux for every dyno run so I doubt I will be having it dyno'd anytime soon.
As far as butt dyno the car seems faster to me I have that working with the boost bypass mod that maven clued me into and so far no codes or limp mode.
I am going to get a mechanical boost gauge and hook it up so I can get some real honest readings and not via a MAP sensor which might not even be calibrated to go above 12.5psi.
I am going to do some data logging and compare it to stock runs. I have a pre dyno but it's 85 bux for every dyno run so I doubt I will be having it dyno'd anytime soon.
As far as butt dyno the car seems faster to me I have that working with the boost bypass mod that maven clued me into and so far no codes or limp mode.
I am going to get a mechanical boost gauge and hook it up so I can get some real honest readings and not via a MAP sensor which might not even be calibrated to go above 12.5psi.
#19
Originally Posted by redrocket
Zinner, can you let us in on the bypass mod. Fear of trouble codes is whats keeping me from doing a pulley change. Need help! thanks
#23
Moderator Alumni
Thread Starter
I didn't have to replace the belt since the tensioner could take up the extra slack.
I took it to the dyno and I didn't make really any extra power, I am not sure if it's because it was so hot out (95 degrees) or if it really didn't make a difference.
I took it to the dyno and I didn't make really any extra power, I am not sure if it's because it was so hot out (95 degrees) or if it really didn't make a difference.
#25