Can a 2.4 carb engine ever be built up to beat a 2.5 efi?

[Krazymaan]

Like the title says. I am very curious if a modified 2.4 non fishing carbed engine can ever beat out a stock 2.5 efi 260,280 or 300hp? Lets just say they both have ROS 20" mids and the same lower unit and the same prop and I suppose the same boat too.
Apples to Apples except the powerhead of course.
No way, just can't. Physics.
Absolutely, If you dial it in right.
Depends.

Whats the verdict?

[Krazymaan]

I would have thought at least one person would know the answer by now.

[speedinstream]

They use to build tuber 2.4 that were pretty strong probly run with a 260 but a 280 or a drag don't think so

[timmc6]

They use to build tuber 2.4 that were pretty strong probly run with a 260 but a 280 or a drag don't think so

Maybe your 260!!!! Lol

[David - WI]

I don't want to start anything, I know guys have built some bad-ass 2.4L motors; but I think it's a lot harder to do. I have one of each and they're both in pieces now. LOL

The 2.5L motor is a better design and breathes better; so it wouldn't be "apples-to-apples" even if you did build a 300hp 2.4L... it still wouldn't have the low-end and mid-range power that the 2.4L motor does - so you still lose any race. It would (probably) be harder to prop, harder to set-up the boat, and harder to drive fast because you don't have the more forgiving power curve of the 2.5L motor to work with.

I think it would also be less reliable / more prone to failure because it would probably take a lot more compression and more radical port timing to make up for older design's limitations.

[timmc6]

Ok not trying to be smartass,why did Mercury go up in stages ,you go from piston ported early to block porting,later ,we are talking a 50 + year evolution!! So the later years probably would be a lot better!!

[Krazymaan]

I don't want to start anything, I know guys have built some bad-ass 2.4L motors; but I think it's a lot harder to do. I have one of each and their both in pieces now. LOL

The 2.5L motor is a better design and breathes better; so it wouldn't be "apples-to-apples" even if you did build a 300hp 2.4L... it still wouldn't have the low-end and mid-range power that the 2.L motor does - so you still lose any race. It would (probably) be harder to prop, harder to set-up the boat, and harder to drive fast because you don't have the more forgiving power curve of the 2.5L motor to work with.

I think it would also be less reliable / more prone to failure because it would probably take a lot more compression and more radical port timing to make up for older design's limitations.

So not going too extreme on the weight issue one way or the other. Just questions for personal knowledge, I'm sure others are curious too especially the 2.4 guys like me. A 700lb race boat with a 275lb 2.4 mod vp or stronger would stand no chance against a 1100lb heavier race boat with a 475lb 2.5 something or other.? with the same mid and prop and fuel and stuff.
You saw my signature right?

[timmc6]

2.4 and 2.5 race motors weigh no less than 10lbs difference,I am not comminenting on boat weights.

[Krazymaan]

I just read that an Optima 300XS weighs in at 505lbs.
I know that my 2.4 Oval Port Mod Vp weighs in at 350lbs.
I'm not about to argue because my knowledge in very limited but thats more than 10lbs.

[90 5.0]

I just read that an Optima 300XS weighs in at 505lbs.
I know that my 2.4 Oval Port Mod Vp weighs in at 350lbs.
I'm not about to argue because my knowledge in very limited but thats more than 10lbs.

Thays a 3.2l motor not a 2.5. 2.0/2.4/2.5 all weigh very close to the same.

There is a 100lb weight difference in SS classes between a 2.4 and 2.5 fishing motor.
In lake racer there is a 300+ lb difference between a SS 2.4 and a s3000

just for what it's worth. Now a full effort 2.4? I think i saw a land and sea add somewhere claiming 300+ out of one, but it ain't gonna hang with a drag

you can make one run, I'm trying for the heck of it. For the weight break. Prolly stupid but we'll see and i like being different!!

[Krazymaan]

I learn something everyday.
So basically a 2.4 might be able to stick to your ass but it ain't going to naturally pass up your 2.5 for the most part based on block design and injection. That seems to be what I am hearing.

[Krazymaan]

Thays a 3.2l motor not a 2.5. 2.0/2.4/2.5 all weigh very close to the same.

There is a 100lb weight difference in SS classes between a 2.4 and 2.5 fishing motor.
In lake racer there is a 300+ lb difference between a SS 2.4 and a s3000

just for what it's worth. Now a full effort 2.4? I think i saw a land and sea add somewhere claiming 300+ out of one, but it ain't gonna hang with a drag

you can make one run, I'm trying for the heck of it. For the weight break. Prolly stupid but we'll see and i like being different!!

Are you saying your going to try to build a balls to the walls 2.4?

[flabum1017]

Ok not trying to be smartass,why did Mercury go up in stages ,you go from piston ported early to block porting,later ,we are talking a 50 + year evolution!! So the later years probably would be a lot better!!

Wait til they come out with the 12,000 rpm wankel engine

[eli]

i think a 2.4 can make 240 hp and run fine and be somewhat reliable
i know a guy who can make hp out of any 2 stroke if you want i can get his name he is going to tickle my 245's
20 hp more in each

[90 5.0]

Are you saying your going to try to build a balls to the walls 2.4?

No in outlaw class there is no weight break for a 2.4 vs a 2.5. If I was gonna build a full effort "balls to the wall motor it would be a 2.5 drag or a v8 rude.

Im building a super stock legal 2.4 to run in super stock class. See if I can make the 100lb weight break worth it. It will probublay be a failed effort as everyone has gone to 2.5's in super stock and I'm sure there's a reason but hey what's the fun in doing the same as everyone else!

Will run a 2.5 prostock the following year , that's the plan anyway and keep stepping up in classes.

Will play with some N2O on a river motor I have too.