i have a built gsr motor tuned on neptune.. all of a sudden it started bogging out at around 3-4000 rpms. i cant figure out the situation..i replaced the dizzy, same problem. fuel pressure is good. any ideas? thx guys

 

How the plugs? Wires? Check all the simple stuff first. After 4 k does it pick back up?

 

yeah..plugs and wires are good..and yes, after that it climbs real nice and smooth..

 

i'm not sure about these wires you say are good. that's SO common for a leaking wire. look under the hood at night and rev the motor. you may see blue jumping sparks

 

i have the same thing with my stock ls motor

 

ill double-check...but from my experience, if this was the issue, it would be a consistant thing, not just at a pecific rpm..

 

nope, it can be specific

 

mine does the same thing, stock ls..changed plugs, wires, cap, rotor, fuel filter, ran injector cleaner...bogs slightly at 3k rpm, more when the temps still cold..

 

try adjusting your distributor

 

OP, how many sections of the forum are you going to post this in? What intake manifold are you using and what is your ignition timing set at?

 

ignition timing is the other one but usually that shows itself with idle

 

Yes. Jump your service connector and set your timing to 16 degrees BTDC