Engine building ?
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Deal of the Century,
don't hold me to this, but I thinking of letting my VORTECH engine go, less header, soon, very cheep maybe on Ebay, you heard and saw it run this past weekend at the Races, for those that don't follow Racing, Mark Henderson and I got 3rd in Michigan, we ran extremely well but the big bastard couldn't get out of the turns fast enough. So I'm thinking of building my HP500efi, the Joker was burning Race Fuel (smell) and pushing 600+ hp, the Ocean will be an equalizer but many of the Races are in Rivers with tight turns, nothing turns like a Superboat but it takes power to get her going again. I thinking $5k range for 520+ power, you cant beat that price. will make that decision soon, very soon.
Eddie
don't hold me to this, but I thinking of letting my VORTECH engine go, less header, soon, very cheep maybe on Ebay, you heard and saw it run this past weekend at the Races, for those that don't follow Racing, Mark Henderson and I got 3rd in Michigan, we ran extremely well but the big bastard couldn't get out of the turns fast enough. So I'm thinking of building my HP500efi, the Joker was burning Race Fuel (smell) and pushing 600+ hp, the Ocean will be an equalizer but many of the Races are in Rivers with tight turns, nothing turns like a Superboat but it takes power to get her going again. I thinking $5k range for 520+ power, you cant beat that price. will make that decision soon, very soon.
Eddie
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Originally Posted by Pat McPherson
If 500HP is the goal, a 454mag is a good base for modification...
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#13
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There is nothing wrong with rebuilding a 10 year old engine so long as it has not been rotting in salt water.
I did a total rebuild on my 1996 502MagMPI last year for about $2500. The engine was vary tired at 480hours as it had a tough life pushing my buddy's 29' Fountain before I bought it from him.
The short-block is a piece of cake to overhaul.
Bring the block to a machine shop and have them hone the cylinders, clean the oil passages, and install new cam bearings.
The rods should be magnifluxed, shot-peened, and re-sized with new APR bolts.
The crank should need nothing more than polishing with crocus cloth.
Ring, bearings, an oil pump, and gaskets are not a lot of $$ and you should be able to reuse your existing pistons as they are forged.
If you don't have the confidence to complete the work yourself, I would bet a shop local to you would do what I've described for around $1500.
Now you have a short-block that will hold up for many more hours of abuse.
Now your valve train selection and head modification/replacement will decide how much power the engine will make.
A 24' Superboat will run over 80mph with 500HP if set-up properly. 60-70mph cruise, no problem...
I did a total rebuild on my 1996 502MagMPI last year for about $2500. The engine was vary tired at 480hours as it had a tough life pushing my buddy's 29' Fountain before I bought it from him.
The short-block is a piece of cake to overhaul.
Bring the block to a machine shop and have them hone the cylinders, clean the oil passages, and install new cam bearings.
The rods should be magnifluxed, shot-peened, and re-sized with new APR bolts.
The crank should need nothing more than polishing with crocus cloth.
Ring, bearings, an oil pump, and gaskets are not a lot of $$ and you should be able to reuse your existing pistons as they are forged.
If you don't have the confidence to complete the work yourself, I would bet a shop local to you would do what I've described for around $1500.
Now you have a short-block that will hold up for many more hours of abuse.
Now your valve train selection and head modification/replacement will decide how much power the engine will make.
A 24' Superboat will run over 80mph with 500HP if set-up properly. 60-70mph cruise, no problem...
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Patrick
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I was running 5700rpm, 23mir+, 74-75mph gps salt water.
Valve train was changed over to hydraulic roller. Bored out to 461ci, compression 9.35:1.
Dart iron eagle heads, intake by Zul racing Demon carb... 800cfm, i think.
JC perf built the engine, and he knows what was in it. He is one who will help a board member, not sure if he gives secrets away or not.
Razor, where are you located?
Jeff can rebuild your motor reasonably, probably to whatever level you want, and you can dress it yourself.
Give him a call 516.216.0778.
Valve train was changed over to hydraulic roller. Bored out to 461ci, compression 9.35:1.
Dart iron eagle heads, intake by Zul racing Demon carb... 800cfm, i think.
JC perf built the engine, and he knows what was in it. He is one who will help a board member, not sure if he gives secrets away or not.
Razor, where are you located?
Jeff can rebuild your motor reasonably, probably to whatever level you want, and you can dress it yourself.
Give him a call 516.216.0778.
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fasteddy -
I was wondering what name you go by on the board, Great Race. You have seen my boat, I think 500HP would be the ticket for my 24 in the P6 Class. And I do agree with the others that it would be cheaper to rebuild my 454. I would just rather go prepared and not blow an engine. I was talking with Tyler Crokett about some posibilities, and I think his price will be a little too high for me.
Also, I would not mind having 2 engines, One in the boat and on ready to go in the boat. If I loose one I will have something to fall back on.
I was wondering what name you go by on the board, Great Race. You have seen my boat, I think 500HP would be the ticket for my 24 in the P6 Class. And I do agree with the others that it would be cheaper to rebuild my 454. I would just rather go prepared and not blow an engine. I was talking with Tyler Crokett about some posibilities, and I think his price will be a little too high for me.
Also, I would not mind having 2 engines, One in the boat and on ready to go in the boat. If I loose one I will have something to fall back on.
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Stormrider, I live in Michigan, Metro Detroit Area. One of the Guys from the Cat Can Do crew (Won the the P2 Class in Algonac) works at my marina.
I am thinking a 509 or 540?
How much power will my Stock (Square) Heads support? (I will have them redone.) I would think they would be fine at the 500 HP level.
I am thinking a 509 or 540?
How much power will my Stock (Square) Heads support? (I will have them redone.) I would think they would be fine at the 500 HP level.
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Also, My boat was from Massachusetts. It was always trailered but was used on the rivers primarily (brackish) and used in the ocean? There is really no way for me to tell just how bad the corrosion may be.
I think I will just go new components.
I think I will just go new components.
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Your stock rectangular port heads can be modified to support 600HP, but unless you do at least some of the work yourself, it will cost nearly as much as a new set of aftermarket heads.
I had the heads off my 502 bowl ported, milled 0.020", and the valve job done for $650 including new springs. They would likely support 550HP with the port work that was done.
1-800-runsnew sells a 500HP/509 base engine (long block with tin) that dyno's at around 515HP for $5800. It is basically a HP500 with a better cam and comes with a one year warranty. I have bought engines from JK and they do stand by their product.
Have Fun and Happy Boating...
I had the heads off my 502 bowl ported, milled 0.020", and the valve job done for $650 including new springs. They would likely support 550HP with the port work that was done.
1-800-runsnew sells a 500HP/509 base engine (long block with tin) that dyno's at around 515HP for $5800. It is basically a HP500 with a better cam and comes with a one year warranty. I have bought engines from JK and they do stand by their product.
Have Fun and Happy Boating...
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Thanks Pat,
I know you went through the same growing pains that I am just beginning. I think I will build my own, I just now need to figure out the best combination for my purpose. I will build new with World (Merlin III) products. Horsepower of torque, torque or horsepower. 24' Superboats are light, I think I would do better spinning a smaller 23" prop around 5500 RPM (should be around 70) and have the ability to run it to 6000 RPM. The question is, do I try to do it with a 454, 509 or 540? I would probably have the best luck with the 454, less stroke should wind up quicker for me and give me better acceleration between 40 and 70mph.
Any experts out there I would love to here what you think?
I know you went through the same growing pains that I am just beginning. I think I will build my own, I just now need to figure out the best combination for my purpose. I will build new with World (Merlin III) products. Horsepower of torque, torque or horsepower. 24' Superboats are light, I think I would do better spinning a smaller 23" prop around 5500 RPM (should be around 70) and have the ability to run it to 6000 RPM. The question is, do I try to do it with a 454, 509 or 540? I would probably have the best luck with the 454, less stroke should wind up quicker for me and give me better acceleration between 40 and 70mph.
Any experts out there I would love to here what you think?
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Razor,
From what I am reading it sounds like you want something along the same lines as the motor in my boat. Started off as a 454 Mag then the top of the motor was reworked including new carb, intake, rockers, etc she dyno'd at just under 500 hp at 5700 rpms with 502 lb/ft torque at around 4700-4800. Pat talked to the previous owner of my boat and may be able to shed some more light as I am going off of the paper work that I have. The thing about this motor is the mid range punch and the run from 45-75 will throw you almost in the backseat. Also I am back and forth right now between 25p 3 blade and 26 bravo 4 blade. I still have the 3 blade on now so that I can see what handful this boat really is and what I need to look for. Supposedly the 4 blade will tame the ride and chine walk a little bit. BUT the top end prop for this boat is a worked 25 Non plus mirage. Hope this helps a little bit
From what I am reading it sounds like you want something along the same lines as the motor in my boat. Started off as a 454 Mag then the top of the motor was reworked including new carb, intake, rockers, etc she dyno'd at just under 500 hp at 5700 rpms with 502 lb/ft torque at around 4700-4800. Pat talked to the previous owner of my boat and may be able to shed some more light as I am going off of the paper work that I have. The thing about this motor is the mid range punch and the run from 45-75 will throw you almost in the backseat. Also I am back and forth right now between 25p 3 blade and 26 bravo 4 blade. I still have the 3 blade on now so that I can see what handful this boat really is and what I need to look for. Supposedly the 4 blade will tame the ride and chine walk a little bit. BUT the top end prop for this boat is a worked 25 Non plus mirage. Hope this helps a little bit