Dennis Moore, John B, and the HP500 EFI
09-23-2003, 07:09 AM
#31
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Location: KY
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Formula;
I couldn't agree more with you about who I'd have work on a bone stock motor. As for high performance I'd go with Bobby Daniels, Blown 1500, etc.....and not think twice about it.
I think people forget what "high performance" entails, things WILL go wrong...its only a matter of time. Its no ones fault, componets will fail. If you can't live with that or can't afford it then stay with stock power, and maintain that or it will break too.
I couldn't agree more with you about who I'd have work on a bone stock motor. As for high performance I'd go with Bobby Daniels, Blown 1500, etc.....and not think twice about it.
I think people forget what "high performance" entails, things WILL go wrong...its only a matter of time. Its no ones fault, componets will fail. If you can't live with that or can't afford it then stay with stock power, and maintain that or it will break too.
09-23-2003, 10:30 AM
#32
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Posts: n/a
Troutly - Thank You
jdnca1 -
Obviously some changes were made in the book between 1999 (my copy) and 2002 (your copy) but that is no big deal. By the way, the cam lift referenced is not @ .020 but is cam lift +/- .020 measured at the cam (rather than at the valve).
I also think that the 741 (or 16HR) is a waste of time without heads or head work. The gain is not worth the effort on it's own. Bite the bullet and pull the heads at the same time.
formulafastech – In the interest of civility I would pass on even that option.
220BR - thanks for stopping by.
JohnB -
The issue with black engine oil in 5-10 hours has little to do with the HP500 EFI and everything to do with the environment it is run and maintained in. The biggest culprit here is the inability to completely drain the oil when changing it. If you have 10-15% dirty oil remaining, it does not take long to discolor. On the other hand, depending on the oil that you are using, color often has little or nothing to do with health or quality. Many top end synthetics (Torco for instance) are dark by nature and tend to (dis)color differently than non-synthetics.
Is the HP500 EFI rich somewhere? Yes. At 3,250 RPM cold, just as it coming up on the cam, it seems to have a burble that is barely noticeable. Get over it and you are on the cam and in the heart of the powerband. When the engine is warm it is far less noticeable and if you are under load it is a non-issue.
It runs great in the car, stock and modified. I have never had an issue with it that has given me pause. The is nothing that compares to it.
The heat range of the plug is not as cold as you would think and, in my opinion, the style of spark plug is more of a factor than the heat range in the HP500 EFI. I prefer a projected tip plug (the specific plug will vary depending on application - boat or car). In the car I run side gapped 0576 Accel's which are the same heat range as the 43T's but with a projected tip.
I have no issue with the timing curve as it comes from Mercury Racing. I have never had an issue getting past 5000 RPM except when I we are prop testing and that is my fault.
jdnca1 -
Obviously some changes were made in the book between 1999 (my copy) and 2002 (your copy) but that is no big deal. By the way, the cam lift referenced is not @ .020 but is cam lift +/- .020 measured at the cam (rather than at the valve).
I also think that the 741 (or 16HR) is a waste of time without heads or head work. The gain is not worth the effort on it's own. Bite the bullet and pull the heads at the same time.
formulafastech – In the interest of civility I would pass on even that option.
220BR - thanks for stopping by.
JohnB -
The issue with black engine oil in 5-10 hours has little to do with the HP500 EFI and everything to do with the environment it is run and maintained in. The biggest culprit here is the inability to completely drain the oil when changing it. If you have 10-15% dirty oil remaining, it does not take long to discolor. On the other hand, depending on the oil that you are using, color often has little or nothing to do with health or quality. Many top end synthetics (Torco for instance) are dark by nature and tend to (dis)color differently than non-synthetics.
Is the HP500 EFI rich somewhere? Yes. At 3,250 RPM cold, just as it coming up on the cam, it seems to have a burble that is barely noticeable. Get over it and you are on the cam and in the heart of the powerband. When the engine is warm it is far less noticeable and if you are under load it is a non-issue.
It runs great in the car, stock and modified. I have never had an issue with it that has given me pause. The is nothing that compares to it.
The heat range of the plug is not as cold as you would think and, in my opinion, the style of spark plug is more of a factor than the heat range in the HP500 EFI. I prefer a projected tip plug (the specific plug will vary depending on application - boat or car). In the car I run side gapped 0576 Accel's which are the same heat range as the 43T's but with a projected tip.
I have no issue with the timing curve as it comes from Mercury Racing. I have never had an issue getting past 5000 RPM except when I we are prop testing and that is my fault.
09-23-2003, 12:48 PM
#33
Adivanman, Thanks for the information.
I was searching some of my past experiences and remembered motors with chokes set too tight and the black smoke and soot poring out the tail pipes, boats and cars! Fuel being a hydrocarbon, when burned should form CO and CO2. If it is not all burned, because of the lack of oxygen, will convert directly to carbon in the 900+ degree temperatures, and come out the pipes.
In the combustion chamber some of this fuel will adhere to the walls and begin to do a job on the rings. Some can get into the crankcase and cause dilution and some if in the carbonized form can turn the oil black.
In my case the leak down on the center 4 cylinders is over 20%. It's leaking into the crankcase. I'm thinking that the oil on the center plugs is also caused by the blowby which enters the center of the plenum. This is on both motors.
I suspect this may not be normal. If they are fixed what should be done to get more that 175 hours next time. On the cam thing, we have no (no wake zones) here and being a cat we cruise at 60 mph+.
Yes, I am discouraged.
I was searching some of my past experiences and remembered motors with chokes set too tight and the black smoke and soot poring out the tail pipes, boats and cars! Fuel being a hydrocarbon, when burned should form CO and CO2. If it is not all burned, because of the lack of oxygen, will convert directly to carbon in the 900+ degree temperatures, and come out the pipes.
In the combustion chamber some of this fuel will adhere to the walls and begin to do a job on the rings. Some can get into the crankcase and cause dilution and some if in the carbonized form can turn the oil black.
In my case the leak down on the center 4 cylinders is over 20%. It's leaking into the crankcase. I'm thinking that the oil on the center plugs is also caused by the blowby which enters the center of the plenum. This is on both motors.
I suspect this may not be normal. If they are fixed what should be done to get more that 175 hours next time. On the cam thing, we have no (no wake zones) here and being a cat we cruise at 60 mph+.
Yes, I am discouraged.
09-24-2003, 10:09 AM
#34
Offshore Cowboy
Platinum Member
Mucky Transom
I switched my 500 EFI's to CMI pipes that divert the water to a seperate chamber exiting the motor and now don't get any mucky black crap on my transom -- I picked up appx. 1/2 MPH (I know... big deal!), and the boat sounds gooood!
If you like, give Travis Brewer at Mars Marine (281-326-6630) a call. He's a Merc Platinum Dealer, did my pipes and all the motor work on all my high performance boats.
I don't know how well you can see the pipes (headers are kind-of in the way), but attached is a photo.
If you like, give Travis Brewer at Mars Marine (281-326-6630) a call. He's a Merc Platinum Dealer, did my pipes and all the motor work on all my high performance boats.
I don't know how well you can see the pipes (headers are kind-of in the way), but attached is a photo.
09-24-2003, 10:23 AM
#35
Joe,
Are you saying your exhaust is totally dry now? If so and the sooty transom is gone, maybe part of the problem is as Adivanman says, the water entrains the carbon and it then splatters all over the back of the boat. Without the water being present, most of the carbon will blow away with the exhaust!
This makes more sense than water causing the engine to burn richer.
Are you saying your exhaust is totally dry now? If so and the sooty transom is gone, maybe part of the problem is as Adivanman says, the water entrains the carbon and it then splatters all over the back of the boat. Without the water being present, most of the carbon will blow away with the exhaust!
This makes more sense than water causing the engine to burn richer.
09-24-2003, 02:12 PM
#38
Offshore Cowboy
Platinum Member
Yes - to all. The transom and swim platform are always clean.
The exhaust has two thin chambers running down the external side of the exhaust pipes (that flow a small bit of water to keep the pipes cool). In the old days, this set-up also called for drilling a couple 1" holes thru the fiberglass which drained the water that originally ran thru the stock pipes. With this set-up, it's done all-in-one and still keeps the 100% stock look -- however, it now roars like a lion.
The motor is still completely stock and utilizes the water sucked up from the outdrives. Hope this clarifies things.
For a better articulation, give either CMI or Travis w/ Mars Marine (# is above) a call. Sorry, this is the best I can do (as a layman)!
The exhaust has two thin chambers running down the external side of the exhaust pipes (that flow a small bit of water to keep the pipes cool). In the old days, this set-up also called for drilling a couple 1" holes thru the fiberglass which drained the water that originally ran thru the stock pipes. With this set-up, it's done all-in-one and still keeps the 100% stock look -- however, it now roars like a lion.
The motor is still completely stock and utilizes the water sucked up from the outdrives. Hope this clarifies things.
For a better articulation, give either CMI or Travis w/ Mars Marine (# is above) a call. Sorry, this is the best I can do (as a layman)!
09-24-2003, 05:26 PM
#39
Registered
Originally posted by Budman
Good post Mcollins!
Is the GM system to which you referred the same type of system that they are planning to use for their upcoming "displacement on demand" that will cut out cylinders when the engine is under light load?
Good post Mcollins!
Is the GM system to which you referred the same type of system that they are planning to use for their upcoming "displacement on demand" that will cut out cylinders when the engine is under light load?
