Well I have mine off to polish it and found a lot of black stuff build up inside, And am wondering how do you clean it out and will it make a diff in performance?

 

id just spray some carb or brake cleaner around in there..

wont make any real diff in performance, but atleast you know it'll be clean...

 

i took my intake, runners and plenum off and sandblasted everything inside and out, then ported everything, and powdercoated my intake and polished the runners and plenum. It looks real good after all the work and im hoping to see a bit of performance gains as well. But i would sandblast everything inside and out, makes it nice and clean!

 

MrDude_1's right, carb cleaner should work well. I let the runners and plenum sit in the parts cleaner for a while but it stained the plenum - it was clean though! I painted the plenum and runners anyway.

 

Pick up a big Rebbuermaid heavy duty bin at Target that is big enough to hold the plenum lying down. Then get 3 gallons of carb cleaner (the nasty stuff in the cans) and soak the plenum in it for 24 hours. A little work with a stiff bristled brsuh on the inside will remove all traces of the oil sludge.

I wouldn't recommed sand blasting. If any sand is left inside, and it invariably is, and it gets into the engien it can do some serious damage to the pistons, ring, bearings, and valves. Just not worth the risk in my opinion.

 

So by cleaning it out it won't make a diff in air flow? Right now I have the sides polished and I don't want to damage the polished parts. What about none of those long 1' cone shapes brushes like youi would use for wheels (sorry I don't know what they are called)?

 

It may make a minor difference in measured airflow, but I don't think you will notice any power increase. I did this to both the upper an lower manifolds in my old 5.0 Mustang, and it made no noticeable difference. It made me feel better though.

The carb cleaner won't hurt the polishing either. Just thoroughly rinse it with water and dish soap and dry it with compressed air. Oh, and don't get any of the carb cleaner on your skin. It burns, it burns!