I have searched and searched and every thread seems to be an argument about what parts to use and which are junk. I am looking to build an n/a 700hp 540 this winter (changed my mind on the procharger) and I am looking for a good recipe to build off. I already have a 741 cam which I plan to use. Other than that I have a 502 MPI with very low (under 30 hours) that I don't trust because of some issues I have had, so I am building again this winter I like EFI... But will prob switch to carb if it is easier and more cost effective. Any help would be great! If anybody needs a 1000hp diesel.... I can help with that! Just not sure on exact parts and specs on the gas side yet... But learning quick! Please just post combos that will get me close to my HP goal, I prefer good parts... As this is hopfully the last time I have to build a motor until I have my "dream" boat

A 540 with the 741 cam is 630-650HP all day, give or take aftermarket head selection and dyno.
Scat 4.25" stroke should be more than enough.

If the lower end is in good condition now. I would take the stroker money and put it into a set of bada$$ heads, intake and cam combo that would run great in a 502 and then upgrade the lower end at a later time when needed. You can get 650hp with a good built 502.

Rookie - anyone you know run the 298cc 24* Oval Race Rite ?

Just wondering howthese are in real world. Came out last year I think.

On paper they look impressive, but we know how that goes. LOl.

Here they are: http://www.brodix.com/heads/big-bloc...block-series24
BP RR BB-3 XTRA O™
• 100% CNC Ported
• 24° Valve Angle
• Flows Over 390 cfm
• 298 cc Intake Port
• Exhaust Ports in Stock Location

I'll be following this thread as I'm looking to do the same thing.

No, those look great! I'll talk to my head guy and ask him what he knows about them.

What size and brand head? if I stay 509?... Sorry above I said 502 MPI... It is actually a 509 MPI. So if I just do heads , cam, intake and exhaust what would I be looking at power wise after tuning? The pistons are forged SRP and the rods are Carrillo.... The crank is stock as are the heads.

The power is ALL in the heads. IF you want to build 700 HP you need better heads - I suggest AFR cnc'd. I had a 741 cam in a 509 and felt it could have used more. That cam is not enough for a 540.
With the right parts it would be hard not to produce at least 700 HP.

What size afr's? 315? I would like to use the 741... As I already have it... But would rather sell and get something better if I will be disappointed in the long run. I will prob stay 509" after talking to my builder. He recommended Brodix heads... But he can get dart and AFR also. I do like AFR as I had them on my mustang and they were bada$$.
And am I best to order them bare and have them built by a marine builder? Or do they come ready to bolt on marine application?

I'm no engine builder but from my internet edukation you definitely want bare castings and get them built up. Even the best mass produced stuff doesn't seem to be within specs for HP marine use.