Hi guys, i just finished the build up of my 355 GM first gen, it has an Howell TBI using stock GM components, engine is mildly modified with the pathetic common components like Edelbrock performer intake and cam, headers ,nothing fancy, it runs ok except for something that i will call misfiring and loss of power at WOT under acceleration, weird thing is that when doing burn out or just revving the engine in neutral it has great throttle response and runs great, apparently the issue happens just under load and from 3000 to approx 5000 rpm on the tach...
Set timing with the timing light, put foam in the fuel tank (trying to keep pick up wet at all times) because i thought was a fuel related problem, than i took off spark plugs this morning and i've seen this:
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Plugs look all like that, they have a white spot on electrode and ceramic surrounded by a dark layer down below.
What do you think about them? Mixture is ok but too hot plugs?
Any help will be greatly appreciated.
Set timing with the timing light, put foam in the fuel tank (trying to keep pick up wet at all times) because i thought was a fuel related problem, than i took off spark plugs this morning and i've seen this:
picture hosting
images
Plugs look all like that, they have a white spot on electrode and ceramic surrounded by a dark layer down below.
What do you think about them? Mixture is ok but too hot plugs?
Any help will be greatly appreciated.