After reading the Tunnel Ram thread, it got me thinking if the 565 intake will fit on a 500 efi. Anybody know? Seems like that intake would cure the power depriving intake of the 500 or even 525, when you start to warm them up?

Yes they will fit. All Mercury did was mount two throttle body's on top of the same intake to fix 500 and 525 breathing problems. The problem with the intake is the runners are to long for HP but do make low end TQ.

all those intakes suck, if you want to make power with the 500 EFI put a carb on it or Whipple it......... Whipples rule.......

On the 565 intake or both?

Haha, I know, everyone basically says the same thing. I was just curious if there would be any gain. I like NA power.

I was under impression the 565 was a "gen 7" block and heads and did NOT share same intake pattern/ head bolt pattern with a gen 6 500 so I would think the intake would NOT line up, bolt on correctly but I may be wrong, Smitty

From microfiche, more like 525efi intake with two tbodies on top

https://www.mercruiserparts.com/565-efi-0m967821-up

Nah. Merc abandoned the 496s. They reworked the old style big blocks for the 430, 520, 540, 565.

The intake manifold is the same, it just has two TBs on top.

Mercury designed those intakes to be stump pullers, good low end torque and pull strong right up to 5200 rpm. They do not respond well to big cu in or rpm. The two things you need to see decent hp gains. Moving the throttle bodies to the top helped clean up flow problems but the intakes still remain very restrictive for big cu in or rpm. I don't think you would see very much benefit going to that intake, especially for what it would cost.

Good info guys. Thanks!