One Reason To Put Larger Intake Valves In A Head

I show some flow numbers and talk about why I’m increasing the valve size a set of Promaxx 290 bbc heads.

[johnweaver]

I had the 2.19 1.88 valves put in my 68 Camaro with closed chamber oval Port head's made a very noticeable improvement, great video keep them coming

[donavan]

FloTek 290 is the same head, but comes with the 2.300 valve standard

[georgedreisch]

At what point does the increasing valve size have a diminished return or even loss for increased shrouding. Would think the low lift numbers would be affected most…

[biastv]

Yeah . 6:30 ish . Sometimes laying back the short turn will stuff flow up. The large, gradual curve is what you need to make the port work

[andy]

did you ever flow these after you took that ridge off?

[richardsmith-qyvl]

Id love to see how much the AFR 265s would pick up with a bigger intake valve and your valve job . Did you do a set with a 0.225 intake valve ?

[jmflournoy]

Do you to a shallow top cut to get rid of the ridge or blend by hand?

[robertoudokrapf]

OLÁ. Olhando a instalação da nova séde de válvulas percebe-se seu parcial conhecimento do assunto que tratas. ABRAÇOS... Roberto Udo Krapf

[davidleary]

I had to change an intake on a very old dart head to 2.35s because they were sunk so much. Hopefully you’ll be getting them for a critique soon and flow them and then beat me up for my chamber work😂

[jakeblack]

Eric, do you believe these results are exclusive to this head? Or will all BBC heads behave similar with a larger valve installed? Awesome video!

[vpackard]

I wonder if opening the chamber adjacent to the intake would help low lift flow with the larger valve. I realize these heads will get returned, but maybe that and an adjustment in seat angles could help.

Thanks for the videos.

[Ghosts_and_Cars]

For a street/strip 461 turbo motor >15 psi would the 290 head be better or would it choke it? Thinking it would have good cruising velocity at low rpm and be more efficient.

[sc.]

On a engine with more cam I'd like to see a dyno comparison of normal valve, then ridge cut in the face for anti reversion (think it was Vizard who talked about that). And then radius of that modified intake valve. A does the face cut help with reversion and if so can you radius the intake thereafter kinda thing.

[humourless]

The idea of enormous valves, and ports to match, always means big numbers on a flow bench, but unless the head is for a race only engine, which is operated WFO pretty much all the time, the results on road vehicle are likely to be disappointing. Venturi type porting, when the intake ducts are actually made smaller, is likely to work better for the road.

[IamYofXY]

I’d like to see the peak flows under boost for this head.

[garyhosier]

I really want to see what happens. How the two compare.

[jmflournoy]

could you use/ try thin MLS gaskets to get the compression up that ridge
AS opposed to sinking the valves to kill low lift flow to make a big cam into a shorter cam
on the larger valve you get a new higher seat which can help unless you have the too early intake opening where you sink the valve (and/or go to steeper seat) cheers how many cuts on the chamber side?

[mohanperformance.enginerd.]

Still lovin and apreciate what you do.
Thank you for your efforts Eric. But the number of ads in this one are a little heavy. Atleast from my perspective. Anyway, Thanks. Great vid as usual. 👍

[patrickwendling]

Thank you for your knowledge and videos USA 🇺🇸 USA 🇺🇸 USA 🇺🇸

[jasoncarver]

If it's going to flow the same or can't be unshrouded in don't matter