Dart cylinder heads
 

Any body use 340 intake volume on a 572 10 to 1 compression motor ? My friend has a 19ft jetboat wants to run 5600 rpm needs cam advice,850 carb,cmi ex,I know big runners kill some low-end torque,any thoughts?

Just an opinion, that's not a big runner on a 572, a CNC ported head may be better.

that is also not enough carb for that combo

I was thinking more like a 1050 carb. I have done a couple of 496's and used 950's on them.

that is more what I was thinking. on my jet boat I ran a 750 DP on my 454 and it probably could have used bigger as it spent all its time at WOT. always felt like it ran out at the top but it was a cheap build and I didnt feel like swapping it.

Have you looked at the AFR 357 magnum or Brodix

I’ve got dart 335s on a 540 . 712 hp @5600 rpm 850 qft carb. Just for reference.

That's not that big a port on a 572. Should be looking at a 1150 or 1250 Dominator. It's gonna need a lot of cam too. Throw all the rules about building little engines out the window when you start building big boy toys.

Do you think 335 is too large for an NA 496? What volume would you recommend for a 572? 355+?

I ran Dart 345`s on a 540 .

You can run whatever cylinder head and carb you want, will it make optimum power for your combination, only the Dyno or GPS can tell you that.

I have old Dart pro1 310 on my 580 cid and numbers are good. I should have the flow bench numbers sometimes this week but my engine dynoed 720hp 5500 rpm and 760 lbs torque around 3500-4000. I'm sure the 345 should be more than enough except if you want to spin this up to 6000 +++ rpm

Small heads
 

I have 615cui engines with 14-71 blowers.
originally built by Tommy @chief engines. And he did set them up with tiny dart 320 heads.
On the dyno after refresh we did see that the Hp curve never stopped gaining. We did stop pulling at 6100rpm but the dyno always turn the engine a couple hundred rpm over and the Hp curve didn’t stop. On the dyno cheat it says 1080hp @6100rpm but we did see just under 1200 up around 6300rpm.

I don’t know what’s right, the heads felt small when I was working on the engines but I figured that Tommy knows what’s his doing and probably had a good reason putting this heads on (or did he just had them laying around) so I left them and planning on a change on the next refresh.

just head size for perspective my 2cents

He put the same heads on my buddies 675hp 6-71 blown 540’s. I’m beginning to think he just used what he had.

Way Back in the day, all there where for aftmkt heads where basically the Dart 320’s, Dart 360’s, and Dart Big Chiefs. Many different shops had porting programs on them, though.

Dart
 

hey what kinda cam ,compression