wieland77

iTrader: (1)

I am going to replace the intake that I have on 502 and rejet the carb. The setup is a 950cfm Holly and a Dart Hi-Rise Intake. I am flooding my intake and not getting correct air/fuel velosity. I am going to et it down to 850cfm and change intake to a more stock, maybe dual plane intake. What intake should I replace with it with?

800XCR

iTrader: (2)

Need more engine info to be much help, but leave the intake and change the carb and maybe flame arrestor.

Longrange4u

I am using an 850 with an edlebrock RPM airgap intake..

KAAMA

iTrader: (1)

What he said plus, it is also important to know what type/brand of exhaust system you're using.(???)

A single plane intake manifold such as a Dart may not work all that well with a stock Merc exhaust system.

dean51267

950 carb is HUGE, 850 is too, you need a LOT of motor to run those, could it be you simply have to much carb? Most 500 ci motors will run really well with 750 cfm carbs.

wieland77

iTrader: (1)

It does have IMCO powerflow exhust. Engine has mild cam but is pretty much a stock 502. I was told that the intake is too tall and obviously my carb is too big so it is flooding. Engine should turn 5200-5400 rpm WOT. What else do I need to provide so you guys can give me a good suggestion? Should I jet back to 750 and leave everything like it is and see what happens or am I wasting time with the intake I have? Thanks

the duke

flooding your intake? As in the gas is pooling in it? where is your float level set at?
what jets in the carb
what PV in the carb

950 is bigger than you need, but in most cases you can make it work. 850 or 800 cfm would be the better choice, but unless you want to spend that money, lets see where you can go with the carb you have first.

ROTAX454

I've just the ticket for you. I have a brand new, in the box GM performance parts #12363407 dual plane, CNC ported manifold for your 502. This is the manifold for the ZZ502 crate motor. Made for a Holley 850cfm on that motor. Look at the following link to a GM parts discount source. You can have mine for $150.00 Bolt on and go. Includes new gasket kit.

articfriends

iTrader: (1)

Carb size has nothing to do with flooding your motor unless by flooding you mean your motor bogs because carb is too big.I would rebuild the carb and set the float levels correctly and see how it runs. As far as your intake is it really a high rise or just a open plenum? Your motor might be soft on the bottom under 3000 rpm's but should run fine in midrange and top end if tuned properly with what you have. What rpm are you turning on the top at wfo? Smitty

Griff

The Dart intake should be fine. The carb is way too big. Get an 800cfm mech secondary carb.