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brwic, what kind of speeds are you seeing with that combo? Do you feel that is enough power for the boat, as far as planing out, and staying on top in rough water, running with a heavy load, etc?

Quote:

Originally Posted by macjazzy (Post 3755052)

brwic, what kind of speeds are you seeing with that combo? Do you feel that is enough power for the boat, as far as planing out, and staying on top in rough water, running with a heavy load, etc?

We have seen 66 @ 5000rpm with 4 people and 1/2 tank of fuel on LOTO and Lake Tenkiller in OK. It is "enough" power, the boat planes easily with the tabs about 1/2 down coming out, then run them up, no need for them, really in any water I've been in, after that. Boat handles big lake chop very well. It would be nice to have more power just for the top end, just depends on what you're looking for.

Quote:

Originally Posted by teaguecustommarine (Post 3662891)

Hey NASCAT,

That Cobalt really came out cool, and it was surprisingly quick for its size. It would be an ideal boat to spend the whole day on. I remember thinking of adding a giant flatscreen under the hard bimini with some satellite TV and it would be party time!

As a performance enthusiast, I would definitely consider buying it as an alternative to your everyday bland "cruiser"

John Teague

Went to sea trial the ILMOR powered 343 you guys did the custom upfit on & it is a masterpiece. Kudos to the owner who took a chance on customizing his brand new boat by stripping the Merc power & drives & adding the ILMOR's as well as Kudos to Teague for the professional rigging job, it's nothing short of 1st class.

Boat gets on plane w/ ease, no tab, accelerates nicely & runs strong.

Quote:

Originally Posted by brwic (Post 3748613)

Hey Guys,
I have an 04 model 343, love the boat, it is all it is cracked up to be have been in LOTO after the Shootout coming out of the cove in some BIG chop and the boat performs great with 5 guys in it. HOWEVER, it is the 496HO/Bravo 1 package and I continually get high (like 250ish) oil temps after over 4k rpm for 10 or more minutes. I have: fresh impellers, cleaned the oil coolers, cleaned the heat exchangers, run full synthetic, have talked to Ray at Raylar, have been in the engine compartment at 4500rpm with a temperature gun checking every hose coming in and out of everything, gauges are reading accurately.......well I've done everything everyone has suggested and still get climbing temperatures. Has anyone had any issue like this? Both engines do exactly the same thing. I love the boat, hate the issues, ready to trade power or trade the boat. Any ideas??
Thanks

I have 525's in mine and the engine compartment temperature has been a problem. I believe Cobalt did some 600 SCi boats that were running very hot. I changed my blower motors to larger capacity units which I run constantly. That seems to help. Good luck.

Pasquesi
Thanks for the info. I may try that next. I have been in that engine box when the boat is running with a infrared temp gun checking temps. Didn't seem that hot but, of course, the hatches were open. We are in the process of putting some 3" x 16" tube oil coolers on it. I'll let you know how that works. May have to do the blower motor exchange too. Appreciate the input.

I ordered some 3X16 Hardin oil coolers and had Keith Scroggin put them on. (Very clean application/installation) Lake tested the boat today ran about 20 minutes at 4500 rpm and 15 minutes (8 miles) at WOT today (air temp about 90) temps never exceeded 205. Before would have been 250/260 and I would have backed it down. Bigger oil coolers are the ticket. Thanks Keith.

I've always been interested in 343's, those of you that have them or have had them what did you think of the center console, helm to the port deal? Did it take some getting used to or no big deal?
Any idea why didn't they put the helm to starboard of center?

Any of the 343's have gen and air? Is there any room to install a genny?

Quote:

Originally Posted by RebarBox (Post 4346208)

Any of the 343's have gen and air? Is there any room to install a genny?

I'm pretty sure that was an option.

When the Ilmors were installed what outdrives did they use ? Or how was that all set up ? just wondering

Also anytime you add horse power to your boat you have to add ventilation and incoming air to the engine compartment. Merc has the specs on this per volume - per horsepower .