I have a few preliminary results from a second dyno session with the replica bathtub intake and a pair of 750 AFB carbs. Total dyno time, about 9 hours. 20 gallons of what is called around here, recreational gasoline. 90 octane, zero alcohol. I am not going to post dyno sheets because the printer is dead and may need to be replaced on the dyno. I will take some screen shots and post next week. Bottom line, that intake with my engine combo at least wants TONS and TONS of fuel!. It's just crazy. The more fuel you throw at it, the more power it makes and I don't have jets or metering rods to make it "too rich". The largest jets for the AFB style carbs are 120's. I had some 116's and it was still pretty lean. Like 14.8-15:1 AFR in spots. So what's a caveman to do? Drill them out of course. So I ran a 1/8" bit through the secondary jets, to see what would happen. It loved it. Picked up 30 HP with that change. But still averaging 13.2-13.7 AFR. It's much smoother now through the pulls but still not rich enough. Also has one very lean spot between primary to secondary transition, when the velocity valve in the AFB is opening and secondary fuel begins to flow. Has a couple hundred RPM spread with high 15:1-low 16:1 AFR. So still some tuning to do. But it's getting close. Picked-up 100 HP yesterday and there is probably 10-15 HP more still out there. But that's just about it IMO. Will play some more after the Norwalk event.
I know people want to know HP and torque numbers so here the peaks so far. 452 Ft. lbs.@ 4800 RPM. 441 HP @ 5900 RPM. I think it's going to finish at about 460 HP.
Two things are really hurting it that were part of the Street engine compromise. Compression is low. Static: 10.1 with aluminum heads. Running on readily available pump gas was a must. The stock iron long branch exhaust manifolds are too small. I can just tell they are really bottled-up over 5200 rpm's or so. You can hear it on the dyno.
Overall, it idles nice @ 1000 RPM, is very snappy and sharp on the primaries with direct linkage, zero leaks, and it looks cool.
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