Max WOT on a 496HO
06-30-2011, 07:50 AM
#11
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06-30-2011, 09:52 AM
#12
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hey guys-
It's in a 06 Cobalt 240. I had it out again yesterday in pretty good conditions and it was the same thing.
If peak power is at 5000rpms, I am not getting there.
The motor will remain in stock trim for quite some time. (light wallet after buying this one!) Maybe some headers next season.
I would imagine the difference in HP at 4775 and 5000 isn't all that much but heck, if I have a little extra sitting there I want it.
The boat runs great and sounds fantastic with the captains call open.
I came from a 5.7Merc in my last boat and the difference is unreal.
What would you guy recommend doing to props other than maybe dropping to a pair of 24's to pick a few hundred rpms?
Thanks
It's in a 06 Cobalt 240. I had it out again yesterday in pretty good conditions and it was the same thing.
If peak power is at 5000rpms, I am not getting there.
The motor will remain in stock trim for quite some time. (light wallet after buying this one!) Maybe some headers next season.
I would imagine the difference in HP at 4775 and 5000 isn't all that much but heck, if I have a little extra sitting there I want it.
The boat runs great and sounds fantastic with the captains call open.
I came from a 5.7Merc in my last boat and the difference is unreal.
What would you guy recommend doing to props other than maybe dropping to a pair of 24's to pick a few hundred rpms?
Thanks
06-30-2011, 09:59 AM
#13
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I poked around a little on this and it looks like the truth is right in the middle! Peak HP is at 5,000 RPM according to Full Throttle Marine: http://www.fullthrottlemarine.com/49...%20Article.htm
06-30-2011, 10:00 AM
#14
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hey guys-
It's in a 06 Cobalt 240. I had it out again yesterday in pretty good conditions and it was the same thing.
If peak power is at 5000rpms, I am not getting there.
The motor will remain in stock trim for quite some time. (light wallet after buying this one!) Maybe some headers next season.
I would imagine the difference in HP at 4775 and 5000 isn't all that much but heck, if I have a little extra sitting there I want it.
The boat runs great and sounds fantastic with the captains call open.
I came from a 5.7Merc in my last boat and the difference is unreal.
What would you guy recommend doing to props other than maybe dropping to a pair of 24's to pick a few hundred rpms?
Thanks
It's in a 06 Cobalt 240. I had it out again yesterday in pretty good conditions and it was the same thing.
If peak power is at 5000rpms, I am not getting there.
The motor will remain in stock trim for quite some time. (light wallet after buying this one!) Maybe some headers next season.
I would imagine the difference in HP at 4775 and 5000 isn't all that much but heck, if I have a little extra sitting there I want it.
The boat runs great and sounds fantastic with the captains call open.
I came from a 5.7Merc in my last boat and the difference is unreal.
What would you guy recommend doing to props other than maybe dropping to a pair of 24's to pick a few hundred rpms?
Thanks
I'd leave it stock and enjoy it, save your money.
06-30-2011, 10:18 AM
#15
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Thread Starter
Not bad advice Dave...
I am in Chicago. While the weather can get pretty hot and humid at times, it's been ideal lately. It was about 75 on very low humidity the last time I tested it.
I did notice on the dyno graphs posted in the link that on a stock 496HO with stock exhaust, there was about a 7 to 8 HP difference between 4750 (where my max rpm is) and 5000 where it made peak power.
I am in Chicago. While the weather can get pretty hot and humid at times, it's been ideal lately. It was about 75 on very low humidity the last time I tested it.
I did notice on the dyno graphs posted in the link that on a stock 496HO with stock exhaust, there was about a 7 to 8 HP difference between 4750 (where my max rpm is) and 5000 where it made peak power.
06-30-2011, 11:01 AM
#16
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just bc you set the limiter at 5400 doesnt mean that the engine will spin to 5400....lab the props to gain 200-400 rpm and you will probably be at 5000-5200 at max throttle without hitting the limiter in the computer,,,whipple can flash the computer for you ,,, and bblades is an expert on bravo 3 props. then enjoy your boat...you probably will only see a gain of 3-5mph at best
06-30-2011, 11:04 AM
#17
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Cj240:
Listen to what most other people are telling you here on this post.
The rev-limit on a stock 496HO is set at 5150rpms for a reason. The stock heavy clunker valves and weak springs cannot take more than that for long periods that this engine is subjected to in boating, so:"DON'T GO THERE!!"
As for squeaking some more rpms and matching good 5000rpms to your boats top speed, do some prop work -maybe labbing and get the rpms there and that will be about all you will ever see without going into the engine with mods like our Raylar kits or possibly 1-2 mph that you may gain from a good header kit like Dana , CMI Sporttubes or Hardin Marine long tubes.
As some have said, save your money, enjoy the summer boating and make meaningful and safe upgrades when you can in the future.
You also need to remember the Cobalt hulls are big and heavy for their size only a 22 degree-V, I believe and are never going to be really fast performance boats as they are considered more a sport performance cruiser.
Best Regards,
Ray @ Raylar
Listen to what most other people are telling you here on this post.
The rev-limit on a stock 496HO is set at 5150rpms for a reason. The stock heavy clunker valves and weak springs cannot take more than that for long periods that this engine is subjected to in boating, so:"DON'T GO THERE!!"
As for squeaking some more rpms and matching good 5000rpms to your boats top speed, do some prop work -maybe labbing and get the rpms there and that will be about all you will ever see without going into the engine with mods like our Raylar kits or possibly 1-2 mph that you may gain from a good header kit like Dana , CMI Sporttubes or Hardin Marine long tubes.
As some have said, save your money, enjoy the summer boating and make meaningful and safe upgrades when you can in the future.
You also need to remember the Cobalt hulls are big and heavy for their size only a 22 degree-V, I believe and are never going to be really fast performance boats as they are considered more a sport performance cruiser.
Best Regards,
Ray @ Raylar
06-30-2011, 01:19 PM
#18
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Thread Starter
Thanks Ray-
I have to agree. I have no major complaints with this baby. For a heavy 24 footer that throws one hell of a wake for boarding and effortlessly runs into the low 60's on the gps that's not to bad.
I wouldn't mind working the props to see max HP right at 5000.
I'll be giving you a call to talk about headers when I am ready.
I recently heard a 496 with Dana headers/thru hull exhaust and it was definitely a different sound.. Very nice indeed..
I have to agree. I have no major complaints with this baby. For a heavy 24 footer that throws one hell of a wake for boarding and effortlessly runs into the low 60's on the gps that's not to bad.
I wouldn't mind working the props to see max HP right at 5000.
I'll be giving you a call to talk about headers when I am ready.
I recently heard a 496 with Dana headers/thru hull exhaust and it was definitely a different sound.. Very nice indeed..
06-30-2011, 01:59 PM
#19
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Forget the headers on the 496. The stock manifolds flow very well. You either go ALL in on a 496, or leave it alone period.
Great engines in stock form that are turn key reliable hour after many hours. Going at it a piece at a time is only going to cost you reliability and aggravation.
Get your props either worked or drop a pitch to put your RPM's in line with your typical load and/or conditions.
Great engines in stock form that are turn key reliable hour after many hours. Going at it a piece at a time is only going to cost you reliability and aggravation.
Get your props either worked or drop a pitch to put your RPM's in line with your typical load and/or conditions.
Last edited by ZP'd; 06-30-2011 at 02:01 PM.
06-30-2011, 03:23 PM
#20
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Forget the headers on the 496. The stock manifolds flow very well. You either go ALL in on a 496, or leave it alone period.
Great engines in stock form that are turn key reliable hour after many hours. Going at it a piece at a time is only going to cost you reliability and aggravation.
Great engines in stock form that are turn key reliable hour after many hours. Going at it a piece at a time is only going to cost you reliability and aggravation.
