Intake

"guys,is there any advantage c

"guys,is there any advantage changing from low rise intake to high rise intake.what makes the differance.is there a fuel use + or -.thanks,larry 350,260 hp,4-bbl,"

"In a stock engine, no, you wi

"In a stock engine, no, you will not see the difference. Power in a V8 is determined by the heads and cam and then the intake and exhaust must be modified to take advantage of the increased airflow. The only advantage is 43 lbs. for a cast iron 4 bbl. intake vs. 13 lbs. for a aluminum intake."

"A standard 350 260 hp engine

"A standard 350 260 hp engine is exactly the same as the 350 270-280 hp engine (marine, mercruiser)

The only difference is the intake, the carb calibration and the flame arrestor. The secondary metering rods are slightly different (more fuel)"

"so, kghost, u are saying that

"so, kghost, u are saying that a std. 350 - 260hp. can achieve 270-280 hp. by changing just the intake, and tweeking the carb., and changing the flame arrestor????????
i have a 350 260hp. and would love to get more out of it. especially if it's that easy. i have a 2bbl. rochester. do you feel that it's possible to achieve the higher hp. with that setup?

i have to be honest, and no offense, but i am skepicle of what your saying. i've heard before that changing to larger carbs, and different intakes doesn't do a whole lot without getting into head and cam upgrades. and, you really threw a curve ball in there when you started talking about a different flame arrestor making a h.p. difference.

what's everyone elses take on this?"

I agree with Jeremiah..I insta

I agree with Jeremiah..I installed a new AL intake with 4bbl carb and all I got was a higher gas bill at the fueling dock..keeping it stock is the best thing until to rebuild..Heads and cam are the keys to more HP with that new intake and carb to match...

"heads or head porting and cam

"heads or head porting and cam upgrade to use the head change provides more HP increase per $$ a stock intake will retain low RPM torque and HP, and is good up to 350-400hp"

"I understand your sceptisism

"I understand your sceptisism

I am talking pre 1995 ish 350's.

I did a part number to part number comparison as far as parts and part numbers for the 260 hp and the 270 - 280 hp. ( every critcal part { cams, heads, pistons, etc.etc.} and the only differsnce is and I will repeat myself AGAIN, is the High rise intake and carb calibration and flame arrestor.

If anyone on this board can admit to bieng able to feel a 10 to 20 hp gain in a avarage boat then you are a very sensitive person because I certainly cant.

Bert The installation of a new al intake and 4 bbl does not guarentee any gains and if not calibrated properly can in fact diminish fuel economy. Seen it many times when done to 305's. Waisted effort for minimal gain. If your carb was to much for a low performance 350 than you would be waisting fuel for the same power output.

Remember is is not diffcult to achive 300 + hp out of a somewhat mild 350 ci motor. The 1986 fuel injected 350 (rare) was rated at 320 hp.

Worked on one in a 18 ft checkmate....75 miles per hour from a factory set up........a real scream!!

SO the potential is there it is just how you make it all come together.

Jeremiah of course a cam change and a rocker arm change and a good dual plane al intake and a Barry grant Marine carb and a Merc Big Block ing module could get you to 350 hp or more!!

So if you want more power it takes some doing and it takes bigger gains in a boat than a car to really apriciate the effort and money spent.

As said here before upgading the enging to say a 383 or something similar where your base engine is well over the 300 hp starting point is the only real way to go unless your engine designing and biulding skills are good enough to do it yourself.

Just my opinion......"

"Gents,,enjoy the Memorial hol

"Gents,,enjoy the Memorial holiday...Happy Boating"