I installed a wood boiler and put the heat exchanger in the plenum and was wondering if i should increase the blower speed, it seems the heat exchanger is restricting some air flow to the vents.
Blower-speed is a calculation based on the CFM needed against the exchange temperature involved. If the exchanger gets very hot, you will need to speed up the fan to remove the excess heat. But you should do this by calculation rather than by guess. Further to this, the amount of CFM your system can pass will be based on the supply and return duct sizes - so there will be top limits beyond which there is no benefit. Also which can be calculated.
