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View Full Version : Volvo Vs. Bravo



Powerquestboy
09-25-2002, 12:45 PM
I was looking for some insight about the volvo set-ups. I currently have a 22 Powerquest with a merc 454 and a Bravo 1 drive and love it. I'm looking at buying a 26 Powerquest with 7.4 GSI Volvo Penta with Duo-prop drive. I was wondering how the 2 compare? Also If I want to put a small supercharger on it will the drive handle the extra power. I have heard the volvos wont and the Bravo will. Any info would be greatly appreciated.

John Cobalt
10-30-2002, 11:03 AM
I think the Volvo's are excellent drives, I have one on a 21ft Cobalt with 5.7GSI 280hp. I know the same drive is used behind the new 496 with 425hp. I like quick hole shot regardless of the amount of people in the boat it is still a lot better with the two props.. Top end on my boat is somewhere around 60mph I have seen 63mph on the speedo. I think that speaks volumes about the drives efficiency coupled to a boat that isn't known for SPEED. The horsepower the drive will take is a good question. I'm thinking you would be
pushing it above 550hp. They are supposed to be extremely strong but how strong I don't know.

Powerquestboy
10-30-2002, 01:17 PM
Thanks for the info, anymore thoughts would be greatly appreciated. It seems like a Chevy vs. Ford thing. Some people love them and some people hate them. I personally only have experience with the Bravos but one of the boats I'm looking at buying a boat with the Duo-prop volvo outdrive.

John Cobalt
10-30-2002, 01:42 PM
My previous boats had Mercs. I changed because I heard so many good things about the reliability of the Engine and Drive. I spoke to Marine Mechanics and sales people a like. The Cobalt Dealer my boat came from wouldn't even order a boat with Merc unless the owner special orders it.
Let me say this if your in it for High Performance there is limited Hi Po stuff for Volvo's specifically. I would like to had different manifolds and a mild procharger but I haven't seen any info on any website specific to Volvo Engines. The ECM's would have to be reprogrammed for the super charger too. Secondly on my application the water impeller is on the front of the crank pulley this is usually where they add a second pullye for a super charger. This could be an issue as well. I'm at a dead end myself on that.

gnarley
10-30-2002, 05:10 PM
I've heard that the faster you go the more drag the dual props present & become less efficient as speed increases. Maybe someone will post what their top speeds are with dual props but I don't think they are in the 80's.

John Cobalt
10-31-2002, 08:44 AM
Gnarley,
I think you are right the dual props would have more drag. The fastest speed I know of without researching this is around 70mph with the Volvo DP in a Cobalt 226 running a 496. I am pretty sure the Volvo DP is more efficient than the Bravo 3 but at the same time for top speed they the Bravo 1's or that new Bravo Single prop drives are hard to beat because their design was specifically for high speed applications and research was done by Merc at lake X to keep the Prop from blowing out at speeds above i think 80mph

SchellSchock
11-01-2002, 10:15 AM
I have a 2000 Glastron 205SF. Not a boat known for speed. I insisted on the Volvo 5.7GSi with the DuoProp drive after much investigation. The dealer tried to talk me out of it cuz' it was a special order item from the factory. The first sign that I made the right choice was the Speedo. The single prop boat comes with a 60 mph and my had a 70mph installed. Running a half tank of gas 3 people in the boat (around 3100lbs total) and air temps in the mid 70s at 500 ft above sea level the boat did multiple passes at 68mph on a GPS. The props pull skiers out no problem and with 3 weight sacks (1050lbs) added it will hold plane as low as 15 mph for wakeboarding. I have read the drive will handle 500 hp no problem. The only down side is prop selection. They are sold as pairs and run about $1,000.00 in the stainles versions. All and all I am totally happy with the package.
P.S. I ran against an Identical boat this summer except he was running the single prop drive. He had 1 passenger, I had 4 and weight sacks filled I still beat him out of the hole and on top end (62 mph on speedo). So draw your own conclusions about the DP as opposed to the SX

John Cobalt
11-01-2002, 12:28 PM
Schellshock what propset are you running F7 or F8, you are smoking with the GSi smoking. 68 on GPS. I wish I could get the cobalt to run like that but Imagine I'm out weighing you cause I've got a big old Stainless wake board tower.

bignblown
11-01-2002, 06:50 PM
the volvo will shift with horsepower in front of it. if you are looking to go a 100mph get a single prop. If you want to ski and have fun duoprop is awsome. I have a buddy that has a 24ft wellcraft W/ 454 runs reall close to 70

RP2
11-06-2002, 01:31 PM
I have ran 74 on GPS @4900 rpm with 7.4 Volvo DP in a 24' boat. Very efficient drive, very expensive props... two sets=$2,000.

SchellSchock
11-07-2002, 02:40 PM
Schellshock what propset are you running F7 or F8, you are smoking with the GSi smoking. 68 on GPS. I wish I could get the cobalt to run like that but Imagine I'm out weighing you cause I've got a big old Stainless wake board tower. John I'm runnin' the F8 set which has been blueprinted and labbed. Thought about bumpin up or down a size but after prop guy got done gained 2 mph and RPM (5100) right were supposed to be.
Yeh 68 in this size boat is a BLAST.

gstark
11-12-2002, 12:29 PM
There was a past issue of Trailer Boats magazine that tested a Cobalt Volvo 5.7 vs. Merc 6.2, head to head, both dual prop I/O's but I don't recall what models. If I remember correctly, the Volvo accelerated faster and had a slightly higher top end.

hammy
11-13-2002, 12:04 PM
I ma conmsidering doing a repwer on my boat and i am m ost likely going to with volvo. I have done extensive research and i should tell you that if you are going to do it right and spend the money you want the dpx drive. It will hold more power and it doesnt have the cavitation probs at higher speeds that the dp has. The dp is an excellent drive but if your going for top end performance you will want the dpx or maybe even the single prop sx drive. The dual props have more drag causing them to be a little slower. Remeber the faster your going the more your problems wil be amplified. I think you wil find that the sx dp and dpx drives all handle considerabled amonts of torque and horse power as long as they are properly maintained and taken care of. I dont know what types of speds your looking for but be mindful that the mercs are designed for high speedsand do hold somewhat of an advantage the higher the speeds get. I am going with the volvo for longevity reasons and because i beleive that for the minimal sacrifice in performance in my particular application it is well worth the durability of the drive. I dont feel that i will be sacrificing much performance but i will be gaining in the quality and reliablity area. I am still learning myself so if anyone has any additional info let me know. hope i could help

SchellSchock
11-13-2002, 03:24 PM
Hammy,
I concur. The DPX drive is the better choice for hp from what I've heard. As far as durability the only prob I have had with mine DP drive is a rip in the shaft bellows allowing salt water to corrode the transom bearing. ($1500.00 R and R), then second time out after fix I didn't know the bait pump was not shutting off and filled the bilge with salt water allowing the same thing to happen. Other than that it has been solid. I've got 160 hrs on drive and it is still smooth as silk

jstwkd
11-13-2002, 04:04 PM
So if I were to have just bought a DP with a 5.7.What could I do to see 60-65.Currently I'm doing 50-52 on gps. 2002 5.7 gxi DP 225 BR crownline.

hammy
11-14-2002, 08:32 AM
Hey jst. We need to know somethings before i can give you any adsvice on hp mods. One, how many rpms is your motor turning at wot when your maxxed out on your gps. 2 exactly what 5.7 do you again? Fuel injected/carb etc. Is it the 250 horse or the 290 horse? Give soem details and maybe i can give you soem advice. Also how much does your boat way and what kind of hull is it? For all you guys otu there wondering how much hp it takes to push your boat a certaib speed there is a company called bam marine out of florida they hAVE A WEB SITE AND I BELIEVE THERE ADRESS is www.go-fats.com (http://www.go-fats.com) they have the formulas on their that mercrury/mercruiser uses to calculate theorectical speed and they also tell you how to calculate ytour prop slip . They have a handly little calculator on the web page itself that will allow tyou to get an idea of what horsepower level you might need to reach the speeds your wanting. remember that this research is by merc usin mer prodcuts so youll need to subtract a few mile per hour or add soem horse power fpor your vovlvo because merc just has a faster lower unit. also need to subtract mpn for duoprops because of ther added drag(yes single prop drives have it a little easier with top end speeds becausse one prop has less drag than 2).As for your cron line im going to guess and say that it isnt a hull know for speed but that its prob a quality boat built for a nice dry ride and superior planing and handling. You habe to remember thqat most speedy hull designs sacrifice planing ability and handling ability because they are designed to run with less surface acrea on the water. The opposite is true for many recreational runabouts. . They are designed to provide good planing fairly low cruisng speeds,good handling,etc. The duoprop drives are used on very few really high performance boats but they are used on alot boatsh that are designed to acceslerate eazasily ,pull skiers,have excelelnt handling.Its liek this jst. youve got a caddilac so making it a speed machine will be more costly than if yuo had a mustang.

John Cobalt
11-14-2002, 10:49 AM
Jstwkd,
I don't think the Crownline 225BR will do 60 to 65mph without a Pro Charger or the like. A very good friend of mine had one with a 350magnum with Captains call and a Alpha or Bravo 1 drive and it maxed out around 53 to 55. If you want that kind of speed you are going to need a lot MORE POWER. Like Hammy said you may need a prop change or something depending on your Max RPM. You have a great boat just don't know that your speed goals will be attainable w/o a lot of Money and HP. That is 13mph increase and thats approx 150hp.

SchellSchock
11-16-2002, 01:53 PM
Yeh.....
What Hammy said....

hammy
11-18-2002, 01:13 PM
Oh and for all of you that were wondering; a late model volvo drive is about as strong as a bravo. The neat part is that you can find the used volvo and have it rebuilt for about the same price as an alpha drive if you shop right , and it will save money over the bravo(not to mention that its hard to find anything other than a new bravo.

HM
11-18-2002, 09:30 PM
My dad has a 23' Sleek Craft with a Volvo 7.4 Duo Prop set-up. Runs 65 and is awesome out of the hole, with 6 passengers, 70 gallons of gas, 2 skiers, and a full 100 qt cooler.
He was told that the DuoProp can handle 600 HP max safely. I think the 7.4 Volvo is 330 HP? Got some nice room for improvement!

RP2
11-25-2002, 09:32 AM
. I think the 7.4 Volvo is 330 HP? Got some nice room for improvement![/QB]I believe that the 7.4 = 385 HP stock.

John Cobalt
11-25-2002, 12:15 PM
Hey guys, Just a word on the Volvo 7.4 DP from 1996 to 2001. There were two models one was a 310hp and the other 385hp. There was also a 8.2L 415 hp model as well (502 cube). Becareful on what one you end up with. The 7.4L 385hp model had a lot stronger bottom end with a much better base for supercharging. I was told the 310hp needed to be beefed up for supercharging. That they just wouldn't hold up under that kind of stress (unless very low boost). Just what I was told.