Thread: Rich Running
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Old 02-26-2002, 01:49 AM
steve G steve G is offline
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Jeff thanks for the suggestion, and you were right, There was a problem with the ignition and advance.

I took ages trying to sort this problem, and after a problem with a noisy pilot bearing on the end of the gearbox shaft, eventually pulled the block (I needed to for the bearing) and took the block along to the engine dyno guy. along with all the movable electic paraphanalia, fuel bits etc. First thing was a base line run, which showed the block running very rich, then leaning out at the top end, first thing he did was rip off the fuel regulator & fitted a replacement, then fitted lighter springs to the holley vac secs, which sorted variance, then on to the ignition, which he set by dwell angle, and vac advance, which was set up at 43 degrees, but there was a lot of discussion here as it was set back to 40 and lost power. we eventually decided that the pointer may not be accurate as TDC, cam alignment etc were all spot on.
The advance was also coming on too aggressively, and this was adjusted with a allen key in the vac chamber. We eventually got 390 hp, 440 torque.

Then we put on the headers supplied with the kit, pulled again, and lost 6 hp over the dyno optimised headers, which was considered OK as my headers did not have a collector (the collector is on the muffler)and may not scavenge properly. we then added sidepipes and lost 30hp. the problem here was we couldn't vent these through the dyno exhaust, and the dyno guy felt that the exhaust was recirculating within the dyno chamber, and reducing the o2 available, causing the drop in performance.

I am not sure at the moment if I have a problem here or not, but the block is running good numbers, not leaning or running rich, I guess I'll have to wait till I get it back together before I know
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