Thread: Big Bog

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Hey guys, this may be a long post, sorry. I have built a nice little .040" over350 cu. in and installed it in my '86 shortbed GMC pickup. It has the following:
9.65:1 cr
GMPP ZZ4 roller cam 211 int/221 ext duration .495/.501 lift
Professional Products Crosswind dual plane intake manfold
Holley 4150 750 cfm carb
GM stock coil/dist
rebuilt 1979 th350 transmission
rebuilt torque convertor stalls at 2200 but I have my doubts
stock differential some where around 2.70 to 3.08 gear
Patriot 190 cnc ported cylinder heads
initial timing at 14.5 all in 35 at 2200
17" vaccum
The truck runs great now that I have swapped in the 750 Holley for a 650 I had originally planned.....except when I go wot from idle (which is 680 rpm in gear) it bogs so severe it stalls the engine. If I leave on the brake from 1300 rpm it runs like we stole it. Idle to 1/2 great. Idle to 3/4 great.
I have adjusted the accel. pumps so there is .015 clearance. I have installed and ran every accel. cam Holley has settling on blue in front flesh/pink in rear.
I will rarely, if ever, run the truck this way. But I would like to know if I'm over looking anything.
Any help is greatly appreciated. Thanks for being here for guys like me.

You set the pump arm to have .015" clearance in the idle position or the WOT position? There should be no slack in the idle position. The correct method is to hold the carb wide open and make sure the arm has at least .015" travel left so that you know the diaphram isn't bottoming out. http://www.youtube.com/watch?v=k-Nx5...B0ABF&index=69

Blue on the front is good. You probably need a blue one on the rear also. What size nozzle is back there. May need to go up a couple sizes. The #2 hole in the blue cam makes it very aggressive.