Engine Bog/Hesitation after shifting

Hey Guys.Not sure if this thread should be in the mixing shop or not.My GS 455 has a TH400 and I notice at fairly hard acceleration (4000-4500) right after the 1-2 or 2-3 shift it seems to nose down or bog for a split second and then resume it`s rpm increase.It has a shift kit and 800QJ.Sound like a carb issue??
Thanks,Later Tony.

 

I just solved that same problem with my Riviera. It ended up being the old fuel filter built into the front of the carb. Dirty and restrictive.

I removed the filter, spring and plunger and installed an inline clear view, re-useable filter and all is well.

Good luck.

 

Thanks.I have been thinking about a in-line filter anyway.Later,Tony.

 

Check your secondary air valve brake with a vacuum source. Make sure it is good. If it is bad, it will let the air valve open too fast and cause a bog.:TU:

 

Thanks George.I will add that to the list! Later,Tony.