Hey HT.

I just completed putting a d15b2 block/pm3-x head, auto trans, and dpfi IM all together into my civic.

The car fires up right away, doesn't bog, doesn't stumble, stutter... no problems with it whatsoever...

EXCEPT-- The car has slightly less power than the old motor (different d15b2, different pm3-x head)


What would cause my civic to feel a little sluggish? When you floor it and hold the throttle all the way open the car climbs up to redline without any weird noises or smells or any symptoms, it's just a little slower than the old motor.

I think it's weird because the new motor was blueprinted w/new piston rings, valve seals, etc by a machine shop. I figured that the new motor would be MORE powerful, not LESS powerful.

I gapped the plugs, set ignition timing, did valve lash ---- what other little tuneups could I do to get my lost power back?

The car has new
-distributor/cap/rotor
-plugs/wires
-radiator
-alternator
-battery
-axles

The block was rebuilt by a machine shop with piston rings (oem pistons) and new bearings.

The head was pressure tested and had valve stem seals replaced...


THERE ARE NO REAL PROBLEMS WITH ANYTHING THE CAR IS JUST A LITTLE SLOWER THAN I EXPCTED.

thanks, I will try any ideas posted...

 

Camshaft may be slightly different compared to the other one (I doubt it but it's possible). Also, since the block was rebuilt by a machine shop did they remove material from the block/head? If so, it might just be enough to alter mechanical timing. Having you double checked you mechanical timing to make sure you're not off a tooth?

 

mechanical timing via timing belt is on point. it is not off a tooth.

i don't know if the machine shop decked/milled the block/head. that is a very goo thing to think about.

ignition timing was set with a timing light, and is on point.

it has an adjustable cam gear (sohc) which is set in the middle (0*, no advance or retard)

anything else to look into?

thanks!

 

Brand of said adj. cam gear? I've heard some manufacturers are slightly off. Maybe try with stock cam gear? Or try moving the cam 1 degree +/- to see if it gets any better?