Post by adamsvega on Sept 12, 2011 16:39:47 GMT -5
is it pulling lean on decell or rich? needles sticking or float sticking on clear sight plugs can drive ya nuts . as ya get on it the bowl level drops and then on decell it over fills and spills out booster. . the next thing to check for decell problems is amount of transfer slot showing . should look like a almost perfect square with the return spring keeping it tight. .(as long as you got narrow slots, some had oversize,measure with feeler gauge ) next is timing .does it return to base or vary .(hei is notorius , jegs kit ,use middle springs and light weight ).where did the idle screws come out to after the swap. ....
Post by montess383 on Sept 15, 2011 22:09:25 GMT -5
Well i took it to the track last night and it went 12.702 at 106 mph right off the trailer. Bumped timing from 8* to 12* and it went 12.6x the rest of the night with 1.8 60ft times. We didnt try changing jets or anything. I got my fuel tester so ill test it tomorrow.
Post by montess383 on Sept 26, 2011 15:33:59 GMT -5
alright this is driving me nuts, part of me wants to convert back to gas because i cant figure this out, and i would like to put nitrous on the car but that isnt going to happen if i cant even get it to run right this way. fuel test at 85%, no matter what size IAB i use and turn the idle mixture screws to get it to idle around 14.7:1 it just leans out and dies when coming to a stop. however if i have it set to idle around 12.5:1 it stays running while coming to a stop and the wideband doesnt show lean while stoping. fuel pressure is set at 6lbs, float height it set to just trickle out of the sight hole. the transfer slot looks like a square. would i be better off converting this carb back to gas, selling it, and buying an e85 carb? or do i need to change the idle passages in the metering blocks or jet down or what?
Post by adamsvega on Sept 26, 2011 16:08:06 GMT -5
IS TIMING LOCKED OUT, MECH. ADV.OR VACUUM/MECH. this is going to sound silly but did try to raise base timing? also your reading it on gas scale for 14.7-1 correct .whos meter ? was it calibrated? is there any exaust leaks or evacs ck valves above 02? does it clear out with a rev. and idle higher and at better afr then slowly hunker down rich and stays at 12.5 .? if you did not have the o2 in there and set the idle by tach/vacuum/ear does it run right ? happy and snappy ....... i have mine set rich at idle with the advance at 15 deg. so it runs like yours at 13-1 on my gas scale but i want it to be cool and cruse nice and snap when the secondarys go open faster than a dp that way of line .....give the car what it wants and if it dont respond adjust the therory not the tune
how does this thing run at wide open and at what afr.
Post by adamsvega on Sept 26, 2011 16:12:05 GMT -5
we can split the idle feed and t slot feed with a jet so you can tune it . if the car runs cruddy at idle and you wanna test this open up the idle feed restriction by .003-.005 after .025 on idle air bleed your not going to get good results we can also change the feed location . are you sure the pv. gasket is not leaking or base gasket. or misaligned metering plate gasket5 holes . .your combo should not not need crazy stuff to be right .
Post by montess383 on Sept 26, 2011 20:34:27 GMT -5
its a vacuum/mech but the vac port is plugged. base timing is at 12* we raised it from 8* when we were at the track at it made no difference with the AFR. the meter is an innovate motorsports LM-1 and its a new sensor and was calibrated. WOT the meter shows 10.9, i do not hear or see any exhaust leaks, it has a lean spike when you get on the gas then gets pig rich. it moderately leans back out to mid 12's as soon as you let off the pedal. i found no vacuum leaks around the carb anywhere, how would i tell if the pv gasket is leaking? i have an extra set of metering block gaskets ill try changing them but i made sure none of the holes or anything were blocked when i put them on. if you stand behind the car the exhaust gases burn your eyes and nose, it feels like standing next to a nitro car.
Last Edit: Sept 26, 2011 20:40:10 GMT -5 by montess383
so wide open your at .80 lamda and you have to set idle screw rich to stop it from a lean stall on decell ? then i would cheak the alignment of the indents in block gaskets and if ok block off both power valve ports and try it . if you snap the throttle in park its ok? we can continue diagnostic with those answers
Post by adamsvegamoble on Sept 28, 2011 5:52:50 GMT -5
well either your meter is reading wrong or the whole curve is fat and its choking out on fuel . with out being there the best i can say is to make a pass and then lean on jets and see if mph goes up on each lean up as you get closer to .80-.85 lambda at wide open .this will confirm it post up what the complete tune up is and where each bleed is at ......its time to play