jetting without power valves

[flattie]

I took the power valves out of my holley 4779 750 double pmp carbs yesterday. I was wondering what jet size everone is running I have 84s all the way around. I haven't been able to drive it due to the weather. Seeing that I have to order the jets because I live 100 miles from no where. I would like some what close on the first nice day.

[Infomaniac]

flattie: Order the jet assortment from Summit or someone like that. It is a big help. Are these the same jets that were in with the powervalves?
I would put 88's in the secondaries and try it from there. I usually jet smaller in the primaries for a little better fuel economy and make up for it when it is really needed. In the secondaries.
Get some sparkplugs that are easy to read. I think I remember you used autolites. They are good plugs but not easy to read when trying to get the engine tuned in.
It is much easier to fix a rich engine that a lean one.

[flattie]

IT HAD #72 IN IT WITH THE POWER VALVES WHEN I INSTALLED THE AFTERMARKET MAIN BODIES IT SAID TO JET UP TO 84 FOR MORE AIR

[triple x tx]

i pulled my powervalves out on my 750s on a tunnel ram application squared them up with 88s worked great......im running 2 850s on a blower application now with no powervalves squared at ninety......but every motor is different......hope this helps

[Kurtis500]

4-5 jet sizes bigger is what I've seen work when taking out the power valves.

[Infomaniac]

Originally posted by triple x tx:
i pulled my powervalves out on my 750s on a tunnel ram application squared them up with 88s worked great......im running 2 850s on a blower application now with no powervalves squared at ninety......but every motor is different......hope this helps
Wisely stated every motor is different.
Interesting fact. A tunnel ram requires more jet than a blower when using the same carb. A tunnel ram has a very poor vac signal under the carb. so more jet is required. A blower has a very strong vac signal so it will pull more fuel through a smaller jet.