carb size recommendations for dual quad 363 stroker

[F-BIRD'88]

That custom made drop base air cleaner BASE is going to make or break this.
Not a lot of room with that hood. The air cleaner will matter. Nice to make a air box tray that seals with the scoop when the hood closes.

Is this your hood?
http://www.mustangdepot.com/OnLineCatal ... /M-306.jpg

This will work out very good for you if you take care of the details.

[Flatheadpopup]

Yep, that is the style of hood I have.

[F-BIRD'88]

Have your air cleaner ready for if when you dyno test and dial in the carbs.
Ya it matters. AND the PCV valve too. Best of you can use your headers also.

[F-BIRD'88]

Because both of the 2 carbs are Universal "primary" carbs they BOTH have PCV vacuum ports and were BOTH designed and set up with the flow of the PCV in mind.
So Hook up the PCV to BOTH carbs. That little air flow thru the PCV at idle and off idle is SHARED
by both carbs.
This is a powerfull effective carb TUNING TOOL to fine tweek (and BIAS if nessessary) the fuel curve so its RIGHT without digging into the carbs idle and off idle fuel circuits which are hard to modify and EASY to FUBAR.
You tweek it by tweeking the air flow RATE thru the PCV valve. Not all PCV valves are the same
and many times the generic ones ARE ALL WRONG for your car.
You can buy a adjustable one. You can modify a $2 stock PCV valve to make it adjustable.
If you ignore this the thing will not be right.
If you pay attention to this you will have dual quads that RUN RIGHT.
The carbs throttle position transition slot exposure at idle is critical ON BOTH CARBS
and the PCV air flow allows you to get it RIGHT.
The motor will want PLENTY of base initial spark advance at idle, that does not jump around at and near idle.
If it wants the distributor locked out, so be it.
If it wants 24-26deg base timing at idle and a short 10deg advance curve so be it. MORE IS BETTER for idle quality and off idle smoothness with that cam and any similar cam like it with auto trans. with eddy carbs and a cammed up motor.

Does not look like you will have a lot of under hood room for carb spacers Sooo.
Bigger carbs will be More powerfull.
If you pay attention to the setup you will NOT have any problems with throttle response
or drivability with 2 BIG ass 750 carbs.

The 650 AVS Thunder series carbs look cool to me too.

[Flatheadpopup]

Thanks for the info F-BIRD'88. The tuning tricks are greatly appreciated. I'll see if I can find the adjustable pcv valve you are talking about as that seems the way to go.

[elmeano]

FBIRD, I like the idea of edelbrock offering a chokeless "race" top. Attached a pic of the old carb I did the horn removal on, also tps bracket, ran this carb for 20years in summer, winter, no choke just prime a couple times and give it the occasional squirt till warmed up in -20below weather. I finally had to switch it out for another- the base of the carb developed a pinhole which would flood the engine when parked.

[F-BIRD'88]

The old 60's era Ford Big blocks like the 406 FE Galaxie etc had a Ford PCV that was made of steel and came apart so it could be cleaned and reused.
Fram still sells replacements. You can open it up to modify the internal spring and pindle valve and flow holes to change how it works.

There is a cool billet aftermarket adjustable PCV. it is pricey but it does what it says. Some of the oem PCV's for 4 and 6 cylinder cars and old 60's ear muscle cars with lower manifold vacuum (big cams) had special PCV's with different operation.

You can dummy rig up a simple ball valve in the PCV hose to tweek the air flow
thru the PCV to see the tuning effect on the carb(s) by retricting flow.
When you find a happy spot install a equal flow orrifice in place of the ball valve,

There is a cool internet hack on how to hack a common right angle type OEM PCV to make it somewhat adjustable. I don't have the links, Google search it.
A AFR gauge and manifold vacuum gauge can show you whats going on
with the PCV. To get to the nitty gritty.


Cool modded Edelbrock carb... You certainly got your use out of that one...ha ha
Its ready for the museum...

[PackardV8]

The old 60's era Ford Big blocks like the 406 FE Galaxie etc had a Ford PCV that was made of steel and came apart so it could be cleaned and reused.
Fram still sells replacements. You can open it up to modify the internal spring and pindle valve and flow holes to change how it works.

Anyone have a Fram p/n for this?

[F-BIRD'88]

Another set of carbs worth looking into for this are the Holley/Demon Street Demon with the unique goggle valve secondary...

[Flatheadpopup]

Another set of carbs worth looking into for this are the Holley/Demon Street Demon with the unique goggle valve secondary...

I'll check them out. Do they fit into the same footprint as the afb or do they need the offset adapter that you mentioned earlier in the thread for the holley conversion? I never did find the guy selling those.

[F-BIRD'88]

They fit inline on the 2x4 afb eddy carb spacing.. Even include a flange shim to ensure the goggle valve clears the flange entry.
AsThe goggle valve is slightly bigger than 1-11/16" throttles Cross..

No experience with it here, but interesting potential.. 625 and 750 cfm versions.

2x750 is nit too much.

[Flatheadpopup]

My first thought was "thermoquad" when I looked at the Street Demons. After reading up a little bit I find them somewhat intriguing. I'll definitely take a better look at them and see what people are saying. Its always good to have alternatives, even if I don't end up going in that direction.

[In-Tech]

The old 60's era Ford Big blocks like the 406 FE Galaxie etc had a Ford PCV that was made of steel and came apart so it could be cleaned and reused.
Fram still sells replacements. You can open it up to modify the internal spring and pindle valve and flow holes to change how it works.

Anyone have a Fram p/n for this?

Yes please. I found some steel screw in pcv's but none that looked to come apart, curious to check the one's Fbird mentioned.

[F-BIRD'88]

Try looking them up by application on the Fram site.
Or the NAPA site, then cross reference.
They are (cast) steel tube shaped with a thread on top.
Inline vac fittings.
62-64 Ford Big block stuff. (Galaxie 500 etc)

This is a aftermarket replacement 427 64 Galaxie
The OEM origional ones where cast steel and threaded together.
You unscrewed the top to service them.
http://contentinfo.autozone.com/znetcs/ ... L/image/3/

There is a cool internet hack that shows how to cut the (newer) sheet metal type open.
Cut that lip to split the cast, then reseal with a heat shrink sleeve tube and a hair dryer.

The old ones thread together.

[F-BIRD'88]

This pic is not the exact one, but is the idea.
Comes apart, Clean reuse, modify....

This one has this stamped ID on it.
Stamped: AC Sparkplug Type CV 619; “IHC 967997-R91”
No idea on this application//// But they are out there.

"international Harvester" ?????

http://forums.ihpartsamerica.com/attach ... 1243874727