Been building these for awhile now using some of Grumps and Paul Blevins mods. Ran them before on my tunnel ram with good results and the AFB's are being a pain so today the swap. I do plan on going through the AFB's over the winter and see if there's something broken in them. Till then the fuel suckers on are on. Runs pretty good just to cold to get a solid tune in them till then they start idle and do good enough.
For those in wonder how to get a center squirt to run decent here some things I did.
1. .013 wire in the idle circuit, this leans them down and I can keep the transition slots way down.
2. I run my jets square just like the factory, many tests done by better folks than me show it does not help significantly to change them
3. I took and placed 3/16 drill bit in the front butter fly and marked the slot and ground it out so that the transition to all fours has a delay
4. I use a two squirter rather than the four so that fuel does not puddle on the back butterflies when cruising. That's my mode I made :-)
5. I am using a two year only rear metering plate off a Ford duel quad for NASCAR motors. These have no PV and work like they came on the 660.
6. Cleaned the transitions in the main body. Was going to 850 plates but I don't really need it.
7. I keep the brass floats. Plastic ones buzz in the gas more and cause the needle and seats to jump some. Think harmonics.
8. Every flat surface has been filed flat with a large file and each hole de burred so there's no leaks and where.
9. Floats are set low and fuel pressure is at 6.5
That pretty much covers the ins and outs of the 660's.