I run this combo, 1050 Dominator, Dart intake, merlin heads on top of 509 cu in making close to 600 hp.

Don''t forget trying the spacer under carb...

One thing I may have left out- Fel-Pro and Merc' gaskets are the same size port..

Sterling used Brodix intakes on my 510 c.i. motors. A friend later changed to the Brodix and gained 200 r.p.m. over the Darts.

From what I've been told ,Brodix is the way to go. I've been using one for 3 years now on my 540.

Ok!!
Who has compared performance between the Dart, Merlin, Brodix and the Weiand Team G on a 502ci???
On an HP 500 that had already been modified from stock being .030 over, 509ci and the cam installed at 110 degrees ILCL, we saw a 200rpm increase with no other changes with the Merlin over the Dart.
I have also heard good things about the TeamG.

Save your money for something else... if you think about it 10 or 20 HP isn't going to add any measurable speed (ok flame away ) sounds like you have already done pretty well.

It's hard, if not impossible, to answer the question as stated unless you hold all other variables constant. Since some of the power comes from that bit of extra cylinder filling caused by the reflected pulse in the intake runner, the "best" manifold is the one that works with your cam, your cylinder head, your CID etc.

I'm no expert on this, but I think of runner length and plenum volume. Runner length affects the timing of the reflected pulse and therefore where it maximizes its effect in the RPM range. Plenum volume and type affect the pulse felt by the carb and its "size" as seen by the engine.

If you're only talking 10-20 HP, that's in line with what you might see (or not) with carb spacers. How well they work depends on what the engine needs.

I have seen on this board the statement that a single plane intake is worth 80 HP on a 500EFI by replacing the stock EFI manifold!! Do you believe that and if so why would it work and what other changes would be needed in the engine to make it work? Food for thought.

Always looking for that last 50-100rpm!!

Dart is in the process of having an intake/head/designer "tweak" their intake manifolds so I would look for some new stuff at PRI in December.

Chris