Volvo Penta 225 V8 (2013 model) needs more power

[mike82j2000]

I have a 2013 21' Regal boat with the new 225 V8 and it's nice and quiet and good on fuel, but I could use some more power. Any more than 4 people seems to bog the motor down and need extra time to plane. Engine runs very nice and smooth and only has 68 hours on it, but I feel it could use a kick in the pants. I should be able to pull way more power from a 5.7L V8.

I understand the engine is tuned down for efficiency and emissions. How can I wake it up a little? Another 30-50 HP would be perfect! Please help.

 

[muc]

The 225 is a 4.3L V6 engine. It's top available horsepower is 240 in 2015 engines. It's possible you could get an extra 15 HP out of your engine but a good prop will probably get you better performance. What prop are you currently running? What other props have you tried?

 

[Bondo]

I should be able to pull way more power from a 5.7L V8.

Ayuh,.... Welcome Aboard,.... If it's a 350, it must have a 2bbl. carb,....

Go to a 4bbl, 'n ya oughta see 260 or better,....

 

[bruceb58]

That engine is MPI and it's a V8.

i thought it was weird as well that they brought out a 225HP MPI V8.

http://www.volvopenta.com/volvopenta...Language=en-gb

 

[mandmj]

Wow. 225 hp from 350ci spinning to 4800 RPM. Its 1986 all over again. It would take a lot of digging to find out (cross checking part numbers on head, cams, injectors, intake manifold, throttle body, compression ratio, etc), but if you got lucky it would only be an ECU change/Reflash to the 300hp or maybe ECU and rocker arms to the 320hp version...

I looked at specs on Volvo's page and it shows the same CR at 9.4:1. One would think that would mean same pistons, and maybe heads. I have doubts about them opening up an engine from GM to change the internals much but maybe a cam change? This may be all ECU tuning, in which case find someone who can reflash it or just buy a new ecu (probably at least a grand) and pick up 75hp.

Back when they had Gi (300HP) and GXi (320HP) 5.7s, the difference was tuning and roller tip rockers that were 1.6:1 ratio vs the standard 1.5:1.

 

[mandmj]

Well, I got curious this afternoon so I decided to ck some part numbers. I ran numbers comparing the 3 following models:

V8-225-c-a
V8-300-c-a
v8-320-c-a

The only difference I found between the 225hp and 300hp engines was the part number for the ECU. The throttle body, cam, rockers, valves, springs, pistons, block, crank, intake, injectors, etc all seem to have identical part numbers for the 2 models (they even usually use the same page on volvopentastore.com)

The 320HP V8 has different rocker arms, springs and ECU from both of the above, but o/w is the same as well.

So, if you knew someone w/ a higher output engine in the same family, a quick ecu change could prove this, but that is unlikely. It might be worth a call to these guys: (or someone similar, I have no experience w/ them, just looked on their site for other reasons).

http://www.obd2allinone.com/mefituning.asp

One question is the MEFI computer you have. I think it is MEFI 5, and programming those may be more difficult. Check out offshore only . com as well for info on custom tunes for the ecu.

HTH.

 

[jerryjerry05]

What kind of RPM's at wide open?
What kind/size of prop?

 

[jhnmdahl]

Is the ECU readily reflashable? This doesn't sound like the kind of thing Volvo's exactly going to promote or make easy.

I have the same engine in a Cobalt, and it pulls pretty well with the duo-prop outdrive until you hit max rpm. I recall Volvo saying the V8-225 and V8-300 had about the same torque until you got to high rpms, where the 300 was mapped for more rpms and horespower.

 

[mandmj]

I seriously doubt Volvo will reflash anything for you, but others here may know. The OEMs are pretty good at guarding their programming on the ECUs, and IIRC, you cant get an ecu reflased w/o a serial number from your engine. I'm speaking of an aftermarket reflash to try to recover the top end power. this type of reflash is something very common in the automotive world, especially on pressurized (turbo/supercharged) motors.

I for one would be curious on these engines to see if the throttle body was even fully open at WOT. Theoretically it would be an easy way to limit top end power by reducing intake cfm (sort of like an old 2 barrel vs a 4 barrel carb) by limiting the amount the throttle body could open. I would think they would have to limit it someway as the cams/valves are the same, and the intake/etc is the same, and otherwise it would make the same power. One cant just reduce injector output or lean detonation will occur. That being said, reduced timing will cut power as well, and it may be some combination of the 2.

 

[jhnmdahl]

mandmj, I think that's exactly right - just never open the throttle body at higher rpm, and you have the V8-225. I did find a place that claims they can reflash it to the V8-300 program, but I'd rarely use the extra high end HP and don't want to muck with the warranty coverage for the time being.

 

[mandmj]

Makes sense. But when the warranty's out....then have some fun! If you are willing, post the info in the thread to the location that will reflash for future reference if other stumble onto the thread.

 

[jhnmdahl]

mandm, sorry I forgot to include the link in my last post. Looks like these guys will do it: http://www.obd2allinone.com/mefituning.asp