bbc hyd roller how should it idle? cam info

[veltex]

How should a bbc hyd roller idle? rough, smooth, in between? Its a Howards set up for max torque, intake .519, exhuast .544, lobe center 112+4, duration at .050 intake 212, exhuast 220. This is in a 454, 049s, 8.8 to 1, edelbrock performer stuff on top, Petrnx Hei dist., runs hard all done by 5000, likes 16 initial 42 total all in by 2800, cant get any more than 15 or 16 on vac guage, idle set at 850, in gear to 650, then in gear air on 550. Vibrates truck some at idle, seams to smooth out when reved up, doesnt sound like a lope though more like a semi miss, plugs look good, any thoughts from the wrench genious guys? thanks

[dwaite72lnghrn]

I've been running a crane cam(hmw-272) about the same size for about 20 years and the idle is smooth. I has a little lope but not rough. My idle with vaccum is about 800-850 in neutral and about 700 in gear. Vaccum is about 19 steady in park and about 18-19 in gear idle. Current carb is edelbrock 1411, The original Q-jet ran about the same vaccum just had better pickup and fuel mileage. The engine is a 402BB but should not make much difference. Are you sure your your gapped at 45 on the plugs? After I had a HEI put in the gap was 35 and the idle was crap till I regapped them.

[veltex]

yeah, I thought the same thing and checked them all yesterday a loose 45, I have the Petronix Flame Thrower Hei, I wonder if I should try a bigger gap? They are AC r44t.

[dwaite72lnghrn]

I would check the idle mixture again, Spin the screws in and counting them don't screw them over tight. Then back them out about 3/4-1 turn hook up a vaccum gauge and tach and adjust for the highest vaccum and watch the RPM when it gets to the highest do the otherside then adjust the idle screw on the side for about 800 then try and adjust the mixture again for a smooth vaccum and RPM. Did the HEI give recomended gap some of them can take up to 60 for a gap. I would think it is idle mixture first though. Just my guess.