whats up guys just posting for a friend. hes got this bogging problem between 3k and 4k and hes also back firing thought maybe running to rich but that seems to maybe lead to a missfire. hes got a b20 block with a b16 head any ideas of what it could be i have a couple but maybe u guys good brighten mine up thanx a lot

 

bump

 

anyone ?

 

check the plugs.. and check the gaps

 

hmm check those already anyone else