Supercat engine questions and ideas
#1
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Hello all.
I'm in the process of restoring / resttifying my 1977 pantera 24-7.
I have a 30hr. 502 from eagle engines that I bought from a member here in June. It's an awesome engine And the plan was to use it to power the 24-7. Last week I picked up a nice early 2000's supercat engine from the dominator to the dry sump pan.
I have some ideas and some questions about my options. Here goes:
I want to sell the 30 hour 500hp 502 and use the supercat engine in the boat.
I'm thinking of dropping the compression to 9.8:1 or 10:1 and having an appropriate cam ground for my application.
I'm thinking of keeping it dry sump as apposed to putting a wet sump system on it. It has the filter boss and the pump mounting intact on the rear main cap so I could wet sump it. I have a killer segmented dry sump pan (five stage) so I'd like to use it. I have to check to see if it will clear my starter and I would need a six stage pump, the lines and a tank.
Some questions / concerns I have are as follows:
Is it easier or more practical to switch the oiling system to a canton set sump pan system?
Does anyone know the cam specs for a 2003ish supercat spec engine?
I'd like to keep the jesel shaft mount rockers and the mechanical roller lifters as its all top shelf gear. I boat about 20 to 30 hours per season so is setting the valve lash once a season that big of a deal?
Are the 312cc intake ports too big for a 509ci 5800 rpm engine? They are "as cast" apba big Brodie 2 plus heads.
Can I mill the domes off the 12:1 pistons enough to drop 2 points of compression? Is this a bad idea? Lol.
The boat will be run at 40 to 50 mph at cruise in Lake Erie and see service as a pleasure boat. I know this engine is overkill but, as a gearhead, I like "too much".
Oh yeah, it's a bravo one drive. I know, I know. Lol.
Any though or suggestions would be greatly appreciated.
Rob.
I'm in the process of restoring / resttifying my 1977 pantera 24-7.
I have a 30hr. 502 from eagle engines that I bought from a member here in June. It's an awesome engine And the plan was to use it to power the 24-7. Last week I picked up a nice early 2000's supercat engine from the dominator to the dry sump pan.
I have some ideas and some questions about my options. Here goes:
I want to sell the 30 hour 500hp 502 and use the supercat engine in the boat.
I'm thinking of dropping the compression to 9.8:1 or 10:1 and having an appropriate cam ground for my application.
I'm thinking of keeping it dry sump as apposed to putting a wet sump system on it. It has the filter boss and the pump mounting intact on the rear main cap so I could wet sump it. I have a killer segmented dry sump pan (five stage) so I'd like to use it. I have to check to see if it will clear my starter and I would need a six stage pump, the lines and a tank.
Some questions / concerns I have are as follows:
Is it easier or more practical to switch the oiling system to a canton set sump pan system?
Does anyone know the cam specs for a 2003ish supercat spec engine?
I'd like to keep the jesel shaft mount rockers and the mechanical roller lifters as its all top shelf gear. I boat about 20 to 30 hours per season so is setting the valve lash once a season that big of a deal?
Are the 312cc intake ports too big for a 509ci 5800 rpm engine? They are "as cast" apba big Brodie 2 plus heads.
Can I mill the domes off the 12:1 pistons enough to drop 2 points of compression? Is this a bad idea? Lol.
The boat will be run at 40 to 50 mph at cruise in Lake Erie and see service as a pleasure boat. I know this engine is overkill but, as a gearhead, I like "too much".
Oh yeah, it's a bravo one drive. I know, I know. Lol.
Any though or suggestions would be greatly appreciated.
Rob.
#4
MarineKinetics
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Vintage,
The Supercat engines were basically a spec platform built with durability and cost control at a premium. It will provide an excellent foundation for your project, however the consumables will need to be validated and replaced as necessary.
I'm thinking of dropping the compression to 9.8:1 or 10:1 and having an appropriate cam ground for my application.
9.7 – 9.9 would be the sweet spot with 93 octane.
I'm thinking of keeping it dry sump as opposed to putting a wet sump system on it. It has the filter boss and the pump mounting intact on the rear main cap so I could wet sump it. I have a killer segmented dry sump pan (five stage) so I'd like to use it. I have to check to see if it will clear my starter and I would need a six stage pump, the lines and a tank.
By all means keep the dry sump. If you plan on pulling vacuum have your pins DLC coated.
Some questions / concerns I have are as follows:
Does anyone know the cam specs for a 2003ish Supercat spec engine?
Yes, you will be ~ 1400-1600 RPM outside your desired powerband (depending upon your induction system) with that cam.
I'd like to keep the Jesel shaft mount rockers and the mechanical roller lifters as its all top shelf gear. I boat about 20 to 30 hours per season so is setting the valve lash once a season that big of a deal?
There is no durability penalty in utilizing a properly designed mechanical roller. Current hydraulic roller lifter technology has made huge gains in bridging the performance delta from the mechanical roller. That being said, you have premium Valvetrain components available to you, it would be a waste to not exploit the performance advantages to be had.
The aluminum rockers have a well defined fatigue life that should not be exceeded. If you cannot properly establish the cycle value for the rockers I would advise you contact Jesel about replacing the arm assemblies as there is no value to refurbishing them. The lifters should go back to Jesel for evaluation.
Are the 312cc intake ports too big for a 509ci 5800 rpm engine? They are "as cast" apba big Brodie 2 plus heads.
No, however there are better heads available for this project.
Can I mill the domes off the 12:1 pistons enough to drop 2 points of compression? Is this a bad idea? Lol.
It may be possible. You would have to first determine the grams per cc of the alloy of your piston (2618) to calculate the amount of material removal necessary to generate the required dome volume. You could then either mill or hand contour the crown area as necessary making sure you do not compromise the structural integrity (checking the topography of the underside of the crown) of the piston.
Bob
The Supercat engines were basically a spec platform built with durability and cost control at a premium. It will provide an excellent foundation for your project, however the consumables will need to be validated and replaced as necessary.
I'm thinking of dropping the compression to 9.8:1 or 10:1 and having an appropriate cam ground for my application.
9.7 – 9.9 would be the sweet spot with 93 octane.
I'm thinking of keeping it dry sump as opposed to putting a wet sump system on it. It has the filter boss and the pump mounting intact on the rear main cap so I could wet sump it. I have a killer segmented dry sump pan (five stage) so I'd like to use it. I have to check to see if it will clear my starter and I would need a six stage pump, the lines and a tank.
By all means keep the dry sump. If you plan on pulling vacuum have your pins DLC coated.
Some questions / concerns I have are as follows:
Does anyone know the cam specs for a 2003ish Supercat spec engine?
Yes, you will be ~ 1400-1600 RPM outside your desired powerband (depending upon your induction system) with that cam.
I'd like to keep the Jesel shaft mount rockers and the mechanical roller lifters as its all top shelf gear. I boat about 20 to 30 hours per season so is setting the valve lash once a season that big of a deal?
There is no durability penalty in utilizing a properly designed mechanical roller. Current hydraulic roller lifter technology has made huge gains in bridging the performance delta from the mechanical roller. That being said, you have premium Valvetrain components available to you, it would be a waste to not exploit the performance advantages to be had.
The aluminum rockers have a well defined fatigue life that should not be exceeded. If you cannot properly establish the cycle value for the rockers I would advise you contact Jesel about replacing the arm assemblies as there is no value to refurbishing them. The lifters should go back to Jesel for evaluation.
Are the 312cc intake ports too big for a 509ci 5800 rpm engine? They are "as cast" apba big Brodie 2 plus heads.
No, however there are better heads available for this project.
Can I mill the domes off the 12:1 pistons enough to drop 2 points of compression? Is this a bad idea? Lol.
It may be possible. You would have to first determine the grams per cc of the alloy of your piston (2618) to calculate the amount of material removal necessary to generate the required dome volume. You could then either mill or hand contour the crown area as necessary making sure you do not compromise the structural integrity (checking the topography of the underside of the crown) of the piston.
Bob
#5
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Thanks for your reply bob. I want to talk to you about grinding me a cam to put the torque curve where it needs to be for my setup.
I have a pair of edelbrock oval port performer rpm heads at the head porter being worked on right now. They came off the hp502 and have 1.89 exhaust and 2.25 intake valves. The intake runner is 290cc. Would these heads and a brodix hp2007 be a better choice for my application?
Thanks again bob! I highly value the advice.
I have a pair of edelbrock oval port performer rpm heads at the head porter being worked on right now. They came off the hp502 and have 1.89 exhaust and 2.25 intake valves. The intake runner is 290cc. Would these heads and a brodix hp2007 be a better choice for my application?
Thanks again bob! I highly value the advice.
#6
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We did what your thinking. We went wet sump do to room restrictions in the bilge. After cam and piston swap we got 650HP out of our Supercats Love them some bad a$$ parts in them for sure.
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[ATTACH=CONFIG]505336[/ATTACH][ATTACH=CONFIG]505337[/ATTACH]
#7
MarineKinetics
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Rob,
The Edel is a 26º head that is primarily an OEM replacement piece.
I would recommend diverting your porting resources into the Brodix. The are as cast w/CNC chambers and will respond well to competent modifications, easily outpacing the Edel ovals. Who is your choice for the porting work ?
Bob
The Edel is a 26º head that is primarily an OEM replacement piece.
I would recommend diverting your porting resources into the Brodix. The are as cast w/CNC chambers and will respond well to competent modifications, easily outpacing the Edel ovals. Who is your choice for the porting work ?
Bob
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Hey Bob. Victory engines in Cleveland Ohio does my machine work. The heads are with a retired machinist that still does porting out of his house. He was doing most of victories work back before cnc became regular practice.
He knows his stuff and has done lots of work for the guys here in the Cleveland area.
I'm going to have him finish the porting as he's half way done but I'll hold him off on the combustion chamber work as I'll be selling the 502 hp complete with the edelbrock heads and intake.
The brodix heads appear to just need a light cleaning as apposed to a reshaping of the runners.
Question on the valves.... Would you think the valves in t he heads are titanium? At least the intake valves with inconel exhaust. If they are titanium intake valves is there a reason to swap them out for a nice Manley stainless?
Thanks, rob.
He knows his stuff and has done lots of work for the guys here in the Cleveland area.
I'm going to have him finish the porting as he's half way done but I'll hold him off on the combustion chamber work as I'll be selling the 502 hp complete with the edelbrock heads and intake.
The brodix heads appear to just need a light cleaning as apposed to a reshaping of the runners.
Question on the valves.... Would you think the valves in t he heads are titanium? At least the intake valves with inconel exhaust. If they are titanium intake valves is there a reason to swap them out for a nice Manley stainless?
Thanks, rob.
#9
MarineKinetics
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Rob,
As per the rules (If this is still a legal spec engine) Ti and Stainless were legal on the intake side with SS and Inconel (no Ti) only on the exhaust. If there are no identifying markings on the valves you may need to weight them for a positive ID.
Here is where component (particularly used) evaluation comes into play. At the forefront, mass reduction, particularly on the valve side of the fulcrum is a huge advantage. If you have low cycle Ti valves on the intake side that show no evidence of seat erosion or fretting, run them. If not, discard the used parts and go with what your budget allows, either SS or Ti..
The exhaust side is far less forgiving. Inconel, period.
Bob
As per the rules (If this is still a legal spec engine) Ti and Stainless were legal on the intake side with SS and Inconel (no Ti) only on the exhaust. If there are no identifying markings on the valves you may need to weight them for a positive ID.
Here is where component (particularly used) evaluation comes into play. At the forefront, mass reduction, particularly on the valve side of the fulcrum is a huge advantage. If you have low cycle Ti valves on the intake side that show no evidence of seat erosion or fretting, run them. If not, discard the used parts and go with what your budget allows, either SS or Ti..
The exhaust side is far less forgiving. Inconel, period.
Bob