KWright

Yes but is the airflow increased by mass volume or speed. A faster flow on a smaller port volume might net better results? Just putting it out there for thought.

SB

We got a few hundred + gallon old dishwashing set up from a restaurant sitting outside for a while for few hundred bucks to feed the sea water pump.

I tell you what, the bravo sea water pump sucked it dry a lot quicker than we thought...would have to leave water hose in it to make a few dyno runs back to back. Those move massive water amounts !

MILD THUNDER

Intake , carb, and cam swap, you gained 33 FT lbs of torque at 5800rpm and 37HP at 5800?, (655HP vs 692HP at 5800). Downside, you lost some Torque, below 4600RPM.

Anytime your HP numbers improve above 5252 RPM from your baseline, you're also making more torque there. Therefore, usually, you see a faster speed.

Full Force

My old engines...565CI,, PBM rotating assembly, 9.5:1 Pro Comp 320 heads, Cam was 236/[email protected], .578/.578 114LSA, Chinese intake, 870cfm Vacuum sec carbs...

Boat ran 73.7 with lots of seat of the past pull from 4000-5500 IN BOAT...25 Mirage plus's@5500... beste speed I saw was even in spit flat water...
[ATTACH=CONFIG]563526[/ATTACH]

New engine 540CI, AFR325's, 9.5:1, cam was 241/[email protected] .681/.663 112LSA boat saw 73.2 ONCE... spinning 25 mirage plus's to 5300... were spec'd to spin existing props to 6000...

[ATTACH=CONFIG]563527[/ATTACH][ATTACH=CONFIG]563528[/ATTACH][ATTACH=CONFIG]563529[/ATTACH]


So new engines made more HP, but tad less TQ, boat was a SLUG and would not even meet old speed let alone faster...

So this years goal was to get things dialed in and move powerband UP... TQ and HP....

bck

Old engines made 660 hp @ 5600. New combo made 706 hp @ 5800. Torque is as shown. Edit- I was told I could've had more significant improvements if I was willing to spin them faster. More on general principle then anything else I refuse to spin motors above 5800

Full Force

The person designing my stuff this time is pretty sharp, we will know if it works when I go boating... so much more comes to play then CC, cams, compression, airflow... ALL needs to be dialed in to really maximize... not just say "this will work" hope myn results prove that.

MILD THUNDER

There's on thing you're leaving out, or forqetting. That was BEFORE, those procomp heads got worked over by Dean Gellner. A fresh valve job, cleanup, etc, and I am sure the engines picked up some power. Had they been dyno'ed after that work was done, I am sure the HP would have increased, and the numbers would have been higher. Prob as high if not higher than the numbers on the current dyno sheets. Those procomp heads, while a chitty chinese casting, were copies of the RHS heads if I recall, and some guys make some big power with them after reworking them. My point? Those old 565's, with those heads, were probably making just as much if not more power than the current 540's with afr heads. Plus, two different dynos, which pretty much means comparing the numbers, is void lol

F-2 Speedy

It is amazing how much water those stock pumps will move, B Smith had an electric primary pump feeding the sea pump to make sure they didnt go dry, his holding tank was also set up to catch rain run off.

MILD THUNDER

To gain 700RPM with same props, my guess, is you're gonna need to be making about 175hp more, than you were. So, about an 800HP 540. That would take you from 72mph, to about 82mph, with same props spinning 6000, instead of 5300. I just don't see 82 in a TRS mistress even with 700's.

Realistically, with a cam change, intake change, my guess, 5500 74-75mph, instead of 5300, and 72-73mph.

Normally, wouldn't be worth it. But since you're cams went to chit, and heads went to chit, its a no brainer at this point to make some changes.

Full Force

LOL I know just comparing I guess, my goal was 700 HP 540's, I did not get that... so I plan to this time .... I HOPE