Merged Collector Holley Tuning

[Walter R. Malik]

There is no free lunch here ... the size of the choke in a collector will only vary the RPM point of the power improvement and may widen it a bit but, it will lose at other places what ever t gains at the RPM place where you want it to be.

[MadBill]

An old Chevrolet Engineering header comparison...

[jmarkaudio]

Can someone post a picture is the transition slot restricter??

I keep hearing about this little tuning thing and never see it on my carb.

Thanks.

This shows the hole tapped with 10-32 thread for using a brass setscrew as a jet to tune the slot.

Well shit...I'm suspecting that's where my issues are. I already purchased a BLP B4X main body. Am I going to have to do this modification to my new main body?

That's for the help.

Didn't mean to hijack the thread.

The BX4 bodies have the t-slot passage threaded 8-32, however if you have a stock or BLP base you rarely need one. Some of the other bases have excessively large t-slots and can benefit from one. On a gas 4150 start with .082 for a hole size in the t-slot passage.

[Tuner]

8-32 or 10-32, it doesn't matter. The picture just happens to be 10-32. With 8-32 the size of the hex limits the orifice to about .073" or .076" because the hex key socket is 5/64" = .078", whereas the 10-32 screw hex socket is 3/32" = .09375". The size of the screw is not important, the orifice size matters. If the screws are not immediately available and it is desired to determine if a restriction of the slot is desirable, a tiny piece of soda can with a hole in it placed between the gasket and the body will suffice.

In the wayback days, when NHRA put extra weight on the HEMI and Jenkins was hurting everybody's feelings in ProStock with a small-block in a Vega using a pair of 660s on a T-ram, Moroso sold a kit of shims which were duplicates of the Holley metering block gasket but with the hole to the T-slot restricted. I think there was an assortment of three sizes (perhaps Big Joe remembers something about this). These were laminated between two gaskets between the block and the body. The obligatory magazine articles touted this as a quick an easy fix for the 660s stupid rich steady speed return road (and street driving ... wink-wink) plug fouling.

[statsystems]

8-32 or 10-32, it doesn't matter. The picture just happens to be 10-32. With 8-32 the size of the hex limits the orifice to about .073" or .076" because the hex key socket is 5/64" = .078", whereas the 10-32 screw hex socket is 3/32" = .09375". The size of the screw is not important, the orifice size matters. If the screws are not immediately available and it is desired to determine if a restriction of the slot is desirable, a tiny piece of soda can with a hole in it placed between the gasket and the body will suffice.

In the wayback days, when NHRA put extra weight on the HEMI and Jenkins was hurting everybody's feelings in ProStock with a small-block in a Vega using a pair of 660s on a T-ram, Moroso sold a kit of shims which were duplicates of the Holley metering block gasket but with the hole to the T-slot restricted. I think there was an assortment of three sizes (perhaps Big Joe remembers something about this). These were laminated between two gaskets between the block and the body. The obligatory magazine articles touted this as a quick an easy fix for the 660s stupid rich steady speed return road (and street driving ... wink-wink) plug fouling.

Thanks Mark and Tuner. I already have BLP 5 emulsion blocks and the billet base plate. Should have said €#£% it and bought a complete carb from the gitgo but I had this one. I'll take some measurements from the old main body and the new one when it gets here.

I'm excited for it to show up. BLP usually has nice stuff.

[Tuner]

BLP base plates are the best I've seen since the OE stuff in the '60s.

[statsystems]

BLP base plates are the best I've seen since the OE stuff in the '60s.

That's good because so far it's about the only thing I've done right.

Going to go back to a 2 emulsion pack or maybe three small ones like Mark said. Three .028's is evidently a bunch of emulsion.