just need to get another opinion, a friends ls vtec runs poorly after replacing the ls timing belt with a gsr belt. compared ls water pump to an ITR water pump, gear looked identical. thanks for the help.

 

The LS water pumps and the Gsr water pumps have a different amount of teeth on them. The LS has 19 and the GSR has 22. You need to match the timing belt up with the same waterpump in order for it to work properly.

 

Does the same timing belt run the water pump as it does the motor?

 

On B-series the timing belt runs the cams and the waterpump.

 

What about D and H series?

 

yes to those as well

 

i could swear that when i replaced the water pump on a friend's ls vtec, the ITR pump that was supposed to go in had exactly the same tooth count. the mounting was different, so the ls pump went back in with a new seal, as it was in good working order in the first place.