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Author Topic:   pulling vacum
posted December 13, 2002 09:11 PM
where i race there told us we had to pull 12" of vacuum. An i don't have a clue how to check it. are what i can do to a motor to pull it. i need any help and what will it do. are there any tricks.

posted December 15, 2002 12:13 PM
idle speed is 1000

rico 08
posted December 16, 2002 01:54 PM
That's an easy rule,ours is 18" at 1000,some tricks are using bleed down lifters with hydraulic cams,specially ground cams,zero gap rings etc.But the cam is the most important try to keep the overlap low as this kills vacuum,most circle track cams have a low lobe center(106-108)this really kills vacuum and makes the engine lope,try some thing in the 112-114 range i beleive crane has some or about anyone can do it with a custom grind,i was reading where the new ls-1 type engines have a 116 degree lobe center and even when the cam is reground and more duration is added they still idle smooth.

posted December 16, 2002 08:48 PM
WE run solid lift. 547 isky and 292 comp.
2bbl. carb. 355cu in. the rest has to bet stock.

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