Hey Chaps

I am using a 1/2 inch small to large boltpatern spacer converter. 4 hole type
for a holley 4150

Had some heat soak issues so I added a 1/2 inch phenolic resin isolator big bolt pattern between carb and isolator BUT

here is the rub - it has one BIG hole - but strangely my fuel distribution has improved.......

Comments please

_________________
Regards,
Fanie Gerber
It's never junk, it's just a part you're not currently using

http://www.valiant50.co.za
Just say I own a few Mopars

What manifold and how is the carburetor oriented? Pictures?

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Joshua

This is where it gets funky

It is a Chrysler SOuth Africa 4BBL manifold designed for the small boltpatern Carteer afb.

In lay out and runner design a lot like the cliffor effort

The carb is at this stage not yet turned 90 degrees wich I would like to do

I even pulled my plugs again - and all seem evenly slgthly dark coloured

_________________
Regards,
Fanie Gerber
It's never junk, it's just a part you're not currently using

http://www.valiant50.co.za
Just say I own a few Mopars

With the open "one BIG hole" spacer, you've increased the plenum volume more than with the 4 hole spacer. That along with the drop in fuel tempature (I'm guessing it's cooler....somewhat at least) would acount for better fuel distribution. From what I've found with most engines, a bigger plenum is usually a good idea. At least until clearance or distrubution problems start to occur.

_________________
There are 3 things that will live forever, cockroaches, Keith Richards, and Slant Six Dusters !!!

http://s4.photobucket.com/albums/y128/slantasaurus/

take a look around

Good call on the plenum size & cooler fuel.


With the bigger plenum size the fuel & air has less velocity, this helps the fuel & air mix make the turn to go to each cylinder easier. It also changes the demand on the boosters & has a effect on jetting. Most of the time it has a leaning effect on jetting.

Inside of the intake manny there is a lot going on and many things can effect the outcome of how it works. I have always liked
a phenolic spacer to, it takes a lot of heat away from the carb itself leaving the fuel much cooler.


In the end when it comes to spacers there seems to be no major rules. Each setup will like its own arangment of spacer & types of holes. Sounds like you found what your setup likes, run with it and enjoy.


Jess

Thanks

The strange thing still is that usually I wold go for a 4 hole adapter + 4 hole isolator, or big hole + big hole. but as I said I have the 4 hole adaptor on the manifold, the "big hole" isolator on top of that and then the carb - cause I couldnt find a 4 hole isolator - I tried the combo for fun and it works

Wonder if the big hole on top of the 4 hole does not act as a sort of mixing chamber, before all is divvied out through the 4 hole spacer

_________________
Regards,
Fanie Gerber
It's never junk, it's just a part you're not currently using

http://www.valiant50.co.za
Just say I own a few Mopars

The only time I've used 4 hole spacers was on V-8 engines with single plane intakes that already had open plenums. The 4 hole seemed to help the signal to the booster in the carb. I'm not saying the open, then 4 hole idea won't work though. I like to experiment too, try it both ways and see if there is any difference or what the engine likes.

_________________
There are 3 things that will live forever, cockroaches, Keith Richards, and Slant Six Dusters !!!

http://s4.photobucket.com/albums/y128/slantasaurus/

take a look around