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Power Loss


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Ok I've done a port n' polish job and replaced my cracked accordian intake with a shorter rubber intake but I've lost power!!

My rear (right hand) exhaust cam was initially off spec by one tooth (inner sprocket) so adjustments were made to the throttle position sensor to fix the idling issues. After the cams were checked due to tapping noises the rear was fixed and the throttle position sensor was readjusted. But theres no tire spin on intial take off (like there was b4 the port n polish) and mid and high-end power is poor.

I had done a few mods b4 the port n polish like:

1. modding the acis valve open

2. leaning out the fuel mixture via afm

Any ideas?? THe port n polish was more like just a thorough polish since hardly any material was removed. The valve stem seals were all replaced (there's no smoke from the exhaust) and the valves were lapped before being reinstalled.

I've tried readjusting the afm to add gas but there's only a slight improvement.

Could it be spark plugs??, injectors??

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It could be plugs, dizzy rotor / cap. Try setting the AFM cog back to where it went originally too.

If all yall did was polish, don't expect much. Where the power comes from is fixing the short side radious, unshrouding the valves & having a good multi-angle valve job done. All of which require actual grinding & cutting. (Material removal)

Check the vacuum of the thing idling (with a vacuum gauge), and check the compression.

How much was the TPS sensor adjusted? If it's not reading correctly now, you may not be getting into open-loop all the way, or even at all.

& check the ignition timing

Valve timing too, that's a common thing when u start playing with cam timing. They'll run way off, but depending which cam is doing what, you can do subtible things like shift the powerband, to major things like wipe out all power in an entire portion of the powerband.

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