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bck 09-29-2016 12:21 PM

Hang Time- it'd be cool if you could dyno with a decent single plane and big carb then try the tunnel ram and compare them. Any chance? Hell, if you're lucky you might find you don't need the tunnel ram to hit the numbers.

Hang Time 27 09-29-2016 12:53 PM


Originally Posted by bck (Post 4486215)
Hang Time- it'd be cool if you could dyno with a decent single plane and big carb then try the tunnel ram and compare them. Any chance? Hell, if you're lucky you might find you don't need the tunnel ram to hit the numbers.

I have no doubt my current current 1050, atop a victor 454R would get me the numbers, since Bob has done a lot of them, but I'm scratching an itch here with the TR. Always wanted to do an 871 for 800hp on this boat, but budget and reliability precluded it. I have found I'm not willing to live with the shorter life of an 871 motor, and running the Chesapeake bay how I like to run only netted me 430 hours out of my Konrad drive with just under 600hp. So the NA 700hp route fits my situation. Doing all my own work has to be rewarded, and a TR will put a big smile on my face every time I lift the hatch �� - plus the room is already there with the scoop, which I could never bring myself to remove.

I'm sure the TR will add power on the dyno if I get it right, but not counting on it in the boat without full length headers - I have SM gen III's - figure at least I won't loose anything. But yea, having the single setup ready for the dyno is a good idea. 

bck 09-29-2016 01:10 PM

I have a 548 with afr 305 heads and Bob's cams that hit 705 on the dyno with a 454R and 4500. I'd love to see what difference a tunnel ram would be. Like you I really don't want to go with a blower for a couple reasons.

Black Baja 09-29-2016 02:01 PM

We made 910hp @6300 on a 588. Edelbrock tunnel ram with 2 1050's. Dart 355cnc heads.
Made 800hp @6300 on a 540. Dart single plane+ Dominator Brodix BB3 332 cnc heads. Swapped to a smaller cam motor lost 20hp on Dyno but picked up low end torque which is normal. Swapped Dart intake for Edelbrock tunnel ram 2 1050's made 850hp with the smaller came and even more torque all the way through.


Both the intakes used were the older Edelbrocks which has a much smaller entry into the runner than the new intake. The entry on the old intake and the new intake isn't optimal for making big power its to small as well as the runner length everything is two small for these kinds of motors. However, they always work better and make more power than a Single plane intake.

bck 09-29-2016 02:07 PM

What's the downside? How'd they idle and shift?

Black Baja 09-29-2016 02:22 PM


Originally Posted by bck (Post 4486249)
What's the downside? How'd they idle and shift?

Shift and idle like a boat motor should. This is with much bigger cams than you guys are running.

Hang Time 27 09-29-2016 09:57 PM


Originally Posted by Black Baja (Post 4486243)
We made 910hp @6300 on a 588. Edelbrock tunnel ram with 2 1050's. Dart 355cnc heads.
Made 800hp @6300 on a 540. Dart single plane+ Dominator Brodix BB3 332 cnc heads. Swapped to a smaller cam motor lost 20hp on Dyno but picked up low end torque which is normal. Swapped Dart intake for Edelbrock tunnel ram 2 1050's made 850hp with the smaller came and even more torque all the way through.


Both the intakes used were the older Edelbrocks which has a much smaller entry into the runner than the new intake. The entry on the old intake and the new intake isn't optimal for making big power its to small as well as the runner length everything is two small for these kinds of motors. However, they always work better and make more power than a Single plane intake.

Nice results on that 540! (and the 588). I assume you mean the old Victor Ram 2r's? That seems to be the power levels, and above of course, where the NEW victor ram intake, along with the dart and profiler, really works. Guys on asphalt then go turn that same 540ci to 8,000 rpm for 1000+hp etc, which is a good clue that those intakes are too large for the sub 6,000 rpm 540 crowd, which is why I choose the 35 year old victor ram 2R - that was designed when smaller cubed motors were more prevalent. The fact that the older ram did so well at your power level backs up my concerns that it's on the large size for my needs, at less rpm and only 700ish hp - but maybe not - only one way to find out.

Another problem seems to be finding a used one that has not had the runners gasket matched up to 2.45x1.72 or larger - I need them uncut to match up with the non-CNC'd AFR 325 ports (AFR's website even says don't gasket match the intake for these heads). I assume the reason for using the uncut 325's at this power level is that they flow at the same velocity as the CNC'd smaller port heads, yet cost less - pretty smart move I thought (Bob, not me). I'll probably have to go new on the intake, but i've got plenty of time to look.

MILD THUNDER 09-29-2016 10:15 PM


Originally Posted by Hang Time 27 (Post 4486404)
Nice results on that 540! (and the 588). I assume you mean the old Victor Ram 2r's? That seems to be the power levels, and above of course, where the NEW victor ram intake, along with the dart and profiler, really works. Guys on asphalt then go turn that same 540ci to 8,000 rpm for 1000+hp etc, which is a good clue that those intakes are too large for the sub 6,000 rpm 540 crowd, which is why I choose the 35 year old victor ram 2R - that was designed when smaller cubed motors were more prevalent. The fact that the older ram did so well at your power level backs up my concerns that it's on the large size for my needs, at less rpm and only 700ish hp - but maybe not - only one way to find out.

Another problem seems to be finding a used one that has not had the runners gasket matched up to 2.45x1.72 or larger - I need them uncut to match up with the non-CNC'd AFR 335 ports (AFR's website even says don't gasket match the intake for these heads). I assume the reason for using the uncut 335's at this power level is that they flow at the same velocity as the CNC'd smaller port heads, yet cost less - pretty smart move I thought (Bob, not me). I'll probably have to go new.

I was not aware AFR made an as cast, 335cc runner head? I thought the 335cc head, was a cnc ported version, of the 325cc "as cast" head.

bck 09-29-2016 10:42 PM

That seems to be the case. Every other head is available with cnc. So a 305 can be as cast or cnc, then then 315 only comes one way. Then the 325 is available as cast or cnc, the 335 is not, etc. Every other size seems to be the cnc'd version of the size below it. So a 335 would be a cnc'd 325 I think.

MILD THUNDER 09-29-2016 11:33 PM


Originally Posted by bck (Post 4486416)
That seems to be the case. Every other head is available with cnc. So a 305 can be as cast or cnc, then then 315 only comes one way. Then the 325 is available as cast or cnc, the 335 is not, etc. Every other size seems to be the cnc'd version of the size below it. So a 335 would be a cnc'd 325 I think.

The way ive understood it, is the 305 is an as cast head, offered with a partial cnc port, which is basically a cnc chamber.

The 315, is a fully cnc ported version, of the 305 casting.

The 325cc head, is avail as cast, or as cast with cnc chamber.

The 335cc,is a full cnc ported version of the 325 casting.


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