i have a 70's holley 6210 double pump quadrajet in need of a rebuild. it has center hung fuel bowls that require 110 needle and seat assembly and not the type for side hung. the question is that the front main body to metering block has a short transfer tube with o-rings that connects the two parts. the rear main body to metering block has the boss for the tube but it is missing. do i need another transfer tube. the holley 37-1537 kit diagram shows the front having one but not the rear. also the kit does not address what size power valves and jet sizes for the carb. does anyone have any info on this.

Man, it's been a LONG time since I messed with one of those!

Primary main jet should be around a 60-62. Primary power valve around an 8.5" unit, stock.

Secondary jetting depends on whether it's got a power valve on that side or not. If not, it's got about an 83 secondary jet. If it's got one, you need about a 65 secondary jet with a 6.5" power valve.

Usually, only the early models have a power valve back there so it's likely yours does not. In any case, I never saw much point having a power valve on the secondary side anyway (by the time you're into the secondaries the power valve is open anyway). In the unlikely event you've got one, I'd just plug it and run the 83 secondary jet by itself.

Can't remember about that tube with the o-rings. Sorry, it's just been too long. If the diagram says no and your carb doesn't have one already I'd say you don't need it.

thanks for the quick reply. you answered my question. the carb does have the provision for a secondary power valve. now i know what size jets to get. by the way today i squirted carb cleaner in the rear discharge nozzle opening and it came out the rear main body opening which would connect to the rear metering body. i thought maybe it was blocked, but it isn't.