Magnum 27 Sedan speeds vs HP
07-05-2015, 01:59 PM
#1
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Magnum 27 Sedan speeds vs HP
If you have seen my build thread, you know I'm Restomodding a 27 Sedan. I have replaced the transom and raised the "X" 3" while updating to the Volvo SP-A outdrives that have integrated trim rams.
I am going to run a pair of Chrysler small blocks, and am beginning to gather parts for their builds. I am starting with a pair of 5.9 Magnum motors from late 90s Dodge trucks, as these had better flowing cylinder heads, and Hydraulic roller cams from the factory. My question is how much Horsepower I should shoot for. Id like to see 75-80 MPH out of the boat (If that is possible) I know the hull is up to it, and it seems as long as I keep the prps in the water the Volvos should hold up ok. The engines stock wit just a swap to a carb are good for 300 HP each, with a mild cam upgrade and some head work I know 400 HP is easily attainable, if I go with stroker cranks they will end up at 408 Cu In and 425-450 HP is not out of the question. My main question is how much do I need? (I know its never enough LOL)
Also I know the center of gravity is different in the sedan, how much does that affect the top speed and handling?
I am going to run a pair of Chrysler small blocks, and am beginning to gather parts for their builds. I am starting with a pair of 5.9 Magnum motors from late 90s Dodge trucks, as these had better flowing cylinder heads, and Hydraulic roller cams from the factory. My question is how much Horsepower I should shoot for. Id like to see 75-80 MPH out of the boat (If that is possible) I know the hull is up to it, and it seems as long as I keep the prps in the water the Volvos should hold up ok. The engines stock wit just a swap to a carb are good for 300 HP each, with a mild cam upgrade and some head work I know 400 HP is easily attainable, if I go with stroker cranks they will end up at 408 Cu In and 425-450 HP is not out of the question. My main question is how much do I need? (I know its never enough LOL)
Also I know the center of gravity is different in the sedan, how much does that affect the top speed and handling?
07-05-2015, 08:09 PM
#3
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I am running the late Chrysler center riser manifolds. I've been told they are worth 15 horsepower compared to the early log manifolds. I am going to make adapters to run Stainless risers from stock Mercruiaer manifolds.
07-05-2015, 10:04 PM
#5
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Gold Member
If you have seen my build thread, you know I'm Restomodding a 27 Sedan. I have replaced the transom and raised the "X" 3" while updating to the Volvo SP-A outdrives that have integrated trim rams.
I am going to run a pair of Chrysler small blocks, and am beginning to gather parts for their builds. I am starting with a pair of 5.9 Magnum motors from late 90s Dodge trucks, as these had better flowing cylinder heads, and Hydraulic roller cams from the factory. My question is how much Horsepower I should shoot for. Id like to see 75-80 MPH out of the boat (If that is possible) I know the hull is up to it, and it seems as long as I keep the prps in the water the Volvos should hold up ok. The engines stock wit just a swap to a carb are good for 300 HP each, with a mild cam upgrade and some head work I know 400 HP is easily attainable, if I go with stroker cranks they will end up at 408 Cu In and 425-450 HP is not out of the question. My main question is how much do I need? (I know its never enough LOL)
Also I know the center of gravity is different in the sedan, how much does that affect the top speed and handling?
I am going to run a pair of Chrysler small blocks, and am beginning to gather parts for their builds. I am starting with a pair of 5.9 Magnum motors from late 90s Dodge trucks, as these had better flowing cylinder heads, and Hydraulic roller cams from the factory. My question is how much Horsepower I should shoot for. Id like to see 75-80 MPH out of the boat (If that is possible) I know the hull is up to it, and it seems as long as I keep the prps in the water the Volvos should hold up ok. The engines stock wit just a swap to a carb are good for 300 HP each, with a mild cam upgrade and some head work I know 400 HP is easily attainable, if I go with stroker cranks they will end up at 408 Cu In and 425-450 HP is not out of the question. My main question is how much do I need? (I know its never enough LOL)
Also I know the center of gravity is different in the sedan, how much does that affect the top speed and handling?
07-06-2015, 05:12 PM
#6
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Just for reference, my 350 made 395 hp with 1.75" long tube headers. Installed the Merc center riser exhaust and knocked it down to 364 hp. Knock it down another ten for logs at that power level.
Are the Chrysler port locations similar to Ford or Chevy?
Are the Chrysler port locations similar to Ford or Chevy?
07-06-2015, 07:34 PM
#7
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Thread Starter
Not close enough. I thought about that already. Interesting enough big block Mopars can be adapted to small block Chevy exhaust manifolds but not small blocks.
07-06-2015, 07:43 PM
#8
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This is my other option. Not sure about the bare head pipe next to the head, though
http://www.hitekmarine.com.au/chrysler.htm
http://www.hitekmarine.com.au/chrysler.htm
