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Discussion Starter #1
the other thread on Vacuum Secondary carbs verses Mechanical Secondary carbs got me to thinking.

I have a 3310C carb..well I have a couple but one has been converted to duel feed metering blocks...what exactly does adding a secondary side metering block inplace of the plate do for you?

thanks in advance:)
 

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Basically switching to a metering block allows you to use standard holley jets on the secondary side. Using a metering block would also allow you to use a power valve on the sec. side; arguebaly an advantage. You can buy metering plates or drill them but it's not as convient. The metering plate has more gaskets, screws etc.
 

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Discussion Starter #4
DriveWFO said:
What about secondary idle mixture screws? Do you get those on VS carbs?

no..........;) :)
hmmm... of cousre I havent looked at mine in a while so my memory could be off somewhat:confused:
 

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Hi,


I like the vac sec carbs. Depends a lot on application as to them or a mech sec..

As far as adding the block, I think you get better emulsification with the block, as well as the jet changing. I have converted a few to "4 corner" idle but Im not real sure if it was an improvement. I thought about adding a rear accelerator pump, using the front pump as the source for fuel, but I haven't tried it yet.

I like the older 3310s the best on larger motors (or high RPM) because the have dropped boosters. The newer straight boosters I use for 383s and comparable "torque type" motors.

I hardly ever use a power valve in the secondary, an sometimes not in the primary.

Casting blems are the biggest problem with these carbs, but easily fixed.

In my opinion I would never the mill the air horn off of one of these carbs. I have seen a bunch of these almost trashed because of this.

Again just my opinion but unless you have the equipment and/or the experience to recalibrate the pri. air bleeds I would leave the air horn alone.


Like I said just my opinions, Im not trying to change any ones minds.


Jeff
 

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I'm in the process of building a 3310 to replace my 600 dbl pumper. I have ordered the metering block and quick change kit for the vacuum secondarys. I used an AED carb kit which is very nice, it even has the secondary diaphram. I'm starting with the stock jetting #72 front and #75 in the rear.

I'm looking at getting a few more miles per gallon over the double pumper!
 

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Discussion Starter #8
loneagle said:
I'm in the process of building a 3310 to replace my 600 dbl pumper. I have ordered the metering block and quick change kit for the vacuum secondarys. I used an AED carb kit which is very nice, it even has the secondary diaphram. I'm starting with the stock jetting #72 front and #75 in the rear.

I'm looking at getting a few more miles per gallon over the double pumper!
I'm not sure what you get now but I used to get about 9mpg on the highway with mine

3.73's, 3000 stall, th350, vic jr, 244/252 duration 518/536 lift, headers, and the 3310 VAC carb
 

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69NovaSS said:
I'm not sure what you get now but I used to get about 9mpg on the highway with mine

3.73's, 3000 stall, th350, vic jr, 244/252 duration 518/536 lift, headers, and the 3310 VAC carb
I don't think I'm getting any better than 10 mpg with the double pumper.
 
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