Can heads from a 5.0L 32valve engine work on a 4.7L engine
01-13-2002, 08:21 PM
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Three Wheelin'
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Can heads from a 5.0L 32valve engine work on a 4.7L engine
Spring project, can heads from a 5.0L with 32valves fit and work on my 4.7L 16valve engine, can I retain the intake and ignition. I know I have to use 32v pistons
Any information is appreciated
Steve C
The Great White
Any information is appreciated
Steve C
The Great White
01-14-2002, 01:51 AM
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Steve,
You should be able to bolt them on. That having been said, there are a few important items that would have to be addressed.
The first is bowl diameter. The bowls of the 32V heads are sized for 100mm cylinders. You have 97mm cylinders. You would either have to rework the top of the cylinders to get a good match and to ensure proper seating of the head gasket, or bore the cylinders to 100mm - which I believe might be pushing it. Without a matching bore, flame propagation and head gasket seating would be seriously compromised.
The second is the whole piston thing. You might be able get your existing 97mm pistons flycut for the 4V valve pockets - though I have not heard of this being done and am unsure what effect this may have on piston integrity. I have seen both 2V and 4V pistons and the pockets are very different in location. Or, you will have to bore the block to accept the 100mm 4V pistons - which may require machine work to the wrist pin and/or con rod.
The third issue would be the ignition and fuel mapping which are different for a 32V motor.
Even doing it yourself, is this really worth your time? (as you could be doing customer work for $XX per hour...) You are going to incur a lot of machine shop time as well as the time spent pulling the motor to swap the pistons and bore the block. And you'll get a pretty small return on a HP per $ basis.
If you want a 4V motor, the least expensive option is just to buy one complete and drop it in. If you need some sources (other than the obvious/expensive ones) I have some contacts - let me know.
Greg
You should be able to bolt them on. That having been said, there are a few important items that would have to be addressed.
The first is bowl diameter. The bowls of the 32V heads are sized for 100mm cylinders. You have 97mm cylinders. You would either have to rework the top of the cylinders to get a good match and to ensure proper seating of the head gasket, or bore the cylinders to 100mm - which I believe might be pushing it. Without a matching bore, flame propagation and head gasket seating would be seriously compromised.
The second is the whole piston thing. You might be able get your existing 97mm pistons flycut for the 4V valve pockets - though I have not heard of this being done and am unsure what effect this may have on piston integrity. I have seen both 2V and 4V pistons and the pockets are very different in location. Or, you will have to bore the block to accept the 100mm 4V pistons - which may require machine work to the wrist pin and/or con rod.
The third issue would be the ignition and fuel mapping which are different for a 32V motor.
Even doing it yourself, is this really worth your time? (as you could be doing customer work for $XX per hour...) You are going to incur a lot of machine shop time as well as the time spent pulling the motor to swap the pistons and bore the block. And you'll get a pretty small return on a HP per $ basis.
If you want a 4V motor, the least expensive option is just to buy one complete and drop it in. If you need some sources (other than the obvious/expensive ones) I have some contacts - let me know.
Greg
01-14-2002, 10:12 AM
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I'm guessing the intake off of a 16V wouldn't fit on the 32V heads.
The question I have is why ? You are better off with a complete 32V engine or add some Euro parts (don't remember your car) and get the power up to 300.
Please keep me posted if you do proceed and if the 16V intake matches the 32V heads.
Good luck.
The question I have is why ? You are better off with a complete 32V engine or add some Euro parts (don't remember your car) and get the power up to 300.
Please keep me posted if you do proceed and if the 16V intake matches the 32V heads.
Good luck.
01-14-2002, 10:17 PM
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Greg, John,
Thanks for the input. Here are my thoughts. My euro M28/22 engine makes 310 crank horsepower. I want more. I know an unmodified 928 engine (without turbo pistons, rods, head gaskets) aren’t reliable when supercharged or turbocharged. Especially with boost pressure over 5 pounds. So why spend 5+ grand for an unreliable engine?
I was thinking of porting and polishing the 32 valve heads, installing a 16v 45mm intake, and 40.00 mm exhaust valves, in lieu of the 32v, 37mm intake and 33 mm exhaust valves.
I want to retain my euro 16v extrudehoned induction system. I feel this system will produce more horsepower then the 32v intake system. I have no data to support my theory. This is just a gut feeling.
I don’t want the hassle of installing a 32v engine, in place of a 16v (rearranging hoses, wires, vacuum lines, plugs, etc). As to ignition and fuel mapping I can chip my controllers or use a piggyback or stand alone engine management system.
If I cant bore my block out to 100mm, ill have to use the 5.0litre engine.
Just some thoughts I’ve been kicking around, don’t know if it’s feasible. What do you guys think? I’m looking for 450 hp.
Steve C
The Great White
Thanks for the input. Here are my thoughts. My euro M28/22 engine makes 310 crank horsepower. I want more. I know an unmodified 928 engine (without turbo pistons, rods, head gaskets) aren’t reliable when supercharged or turbocharged. Especially with boost pressure over 5 pounds. So why spend 5+ grand for an unreliable engine?
I was thinking of porting and polishing the 32 valve heads, installing a 16v 45mm intake, and 40.00 mm exhaust valves, in lieu of the 32v, 37mm intake and 33 mm exhaust valves.
I want to retain my euro 16v extrudehoned induction system. I feel this system will produce more horsepower then the 32v intake system. I have no data to support my theory. This is just a gut feeling.
I don’t want the hassle of installing a 32v engine, in place of a 16v (rearranging hoses, wires, vacuum lines, plugs, etc). As to ignition and fuel mapping I can chip my controllers or use a piggyback or stand alone engine management system.
If I cant bore my block out to 100mm, ill have to use the 5.0litre engine.
Just some thoughts I’ve been kicking around, don’t know if it’s feasible. What do you guys think? I’m looking for 450 hp.
Steve C
The Great White
01-15-2002, 12:37 AM
#5
Steve,
The 928 engine is very adaptable but why reinvent the wheel?
It will be much cheaper to buy and install a complete S4 engine with all the electronics than to modify your engine with 32-valve heads.
Why don't you stroke your 16-valve motor and port your heads? I think the Euro S engine with another liter of displacement should make you very happy. Your engine would be capable of 400 hp with the right mods. You could also supercharge your engine, unless it's a CIS, with the kit from FAST or donate your car to Huntley for their Eaton blower project? Supercharging your engine will be cheaper than doing all the internal modifications it will take to produce big hp from this engine, that is, once again, unless the car uses CIS.
The 928 engine will eat up your bank account faster than a greedy trial lawyer with a personal vendetta.
Jim Nowak
The 928 engine is very adaptable but why reinvent the wheel?
It will be much cheaper to buy and install a complete S4 engine with all the electronics than to modify your engine with 32-valve heads.
Why don't you stroke your 16-valve motor and port your heads? I think the Euro S engine with another liter of displacement should make you very happy. Your engine would be capable of 400 hp with the right mods. You could also supercharge your engine, unless it's a CIS, with the kit from FAST or donate your car to Huntley for their Eaton blower project? Supercharging your engine will be cheaper than doing all the internal modifications it will take to produce big hp from this engine, that is, once again, unless the car uses CIS.
The 928 engine will eat up your bank account faster than a greedy trial lawyer with a personal vendetta.
Jim Nowak
