355 Vortec Tuning. Watch the videos.
#11
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
Tune it on the water. Put a load on it. Sometimes you think you got it all set on the trailer, and you get to the lake, shift it into gear, and it will stall. Idling at 1100-1200, is no good for the drive you have there, when shifting in/out of gear....
Idle Air bleed size, idle feed restrictor size, and that BG idle Eaz deal, all can play a part in where you're mixture screws will need to be. Theres a reason they are adjustable and not fixed. Not all engines require the same settings.
Idle Air bleed size, idle feed restrictor size, and that BG idle Eaz deal, all can play a part in where you're mixture screws will need to be. Theres a reason they are adjustable and not fixed. Not all engines require the same settings.
#17
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Joined: Nov 2004
Posts: 14,154
Likes: 3,714
From: On A Dirt Floor
My question is almost the same but:
Is there a chance the flat tappet cam wasn't broken in yet with this carb fooling around?
BTW: In cold air and non-warmed engine that air gap intake will make it t idle not worth a chit. It will probably want a handful more initial timing.
Is there a chance the flat tappet cam wasn't broken in yet with this carb fooling around?
BTW: In cold air and non-warmed engine that air gap intake will make it t idle not worth a chit. It will probably want a handful more initial timing.
#18
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
I thumbing thru an ''Engine Masters" magazine a little while ago. They had a 500HP small block chevy. They tested 4 carbs.
Holley 4776 600 Double pumper.
Holley 750 Ultra HP
Holley 950 Ultra HP
BG 600
They dynoed each carb on the engine. From 2500-6500RPM. Not only did the 950 Ultra make more peak power, it made more torque than the rest of them, even in the low rpm range of 2500-3000.
The entire point they tried to make in the writeup, was that back in the 70's, bolting on too large a carb just didnt work well. With modern carb technology today, a larger carb, properly setup, can be very responsive, efficient, and work well. A modern 1050 Quick fuel, is a far cry from an 80's 2 circuit Dominator.
Holley 4776 600 Double pumper.
Holley 750 Ultra HP
Holley 950 Ultra HP
BG 600
They dynoed each carb on the engine. From 2500-6500RPM. Not only did the 950 Ultra make more peak power, it made more torque than the rest of them, even in the low rpm range of 2500-3000.
The entire point they tried to make in the writeup, was that back in the 70's, bolting on too large a carb just didnt work well. With modern carb technology today, a larger carb, properly setup, can be very responsive, efficient, and work well. A modern 1050 Quick fuel, is a far cry from an 80's 2 circuit Dominator.
#19
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Joined: May 2010
Posts: 996
Likes: 189
From: Red Oak, Texas
We dyno'ed my big blocks and actually lost alittle going from 750's to 850's. But, having said that, the 850s were Demons the dyno guy sitting there and weren't set up for my motors. We were running at 107%VE and he wanted to see if he could get more air. Didn't work/




