Made 725 with 598s carb and NA on 87 pump gas.

C.I.
 

GT Performance just Dyno'd one of two of my engines that they built 588 C.I. Normally Aspirated with Emtron KV8 ECU, Sequential FI, Closed Loop Fuel Lambda sensors 740 HP
on 87 Octane.

700HP and under N/A

650HP+ Forced Induction

aggressive cam? I still have my Scorpions, I have valvetrain more under control now over what I had before, I admit.... I am worried at times about the Scorpions, then I figure with girdles and all I should be ok... I hope.

If I did what I did again, I would do 502 or whatever with forgfed internals, decent heads and BOOST.... you work the parts so much less to make the same HP, nothing is custom or maxed out, Eddie Young and I had a conversation about this after I got mine done, he pointed out... mild cam, mild springs, no crazy heads needed... just boost and good fuel system...

Tuned right blower motors can be very friendly . 900 hp and I idled around for at least an hour Saturday ( prop hunting) then went down the Chicago river for another 40 minutes of idleing.. never fouled a plug or missed a beat .

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Plus I mean look at those things , it`s boner city :drink:

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If I had one complaint it`s that it sounds like someone killing a cat in my bilge all day long.

What rpm are you planning on turning them?What outdrive?

Big cubes + big blowers = big horsepower + big money (and yes, boner city)

Big cubes NA + efficient hull = fast + reliable boating

(my two cents after owning, operating, and maintaining the former)

Also wet or dry exhaust?
If you are building one that is dry exhaust and turning 5500 rpm then a naturally asperated one will do the job quite well.

If you are wet exhaust or turning it over 6k then I would do a blower.

With an na engine it's hard to get them to idle well and have big numbers at 6000 or above.When you get them to not stall at the dock then 6k and above torque drops like a rock.

But with a blower you can have a smaller cam and still pull at 6k and above.Which gives you good idle and still pulls at higher rpms.

Also with A N/A engine has wet exhaust you are seriously limited on duration and valve overlap.Which means that you would have to run a smaller cam.Which then the engine would only make good torque up to about 5000 rpms.

Hope this helps

Agree...lol..