Higher ratio rocker arms and 6.2 MPI engines
08-25-2008, 02:03 PM
#11
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Sounds easy enough Dustin, but do you have any examples demonstrating the long term reliabilty of a swap like this on stock 6.2's? I have the same boat as rhsj2006 (292 Fastech) and they are pretty heavy boats.
Couple questions. What boost and what octane is required in your example to get 15 mph? These engines only hold 4.5 qrts of oil. Is a $140 cooler enough, or should you try an increase the capacity? Does the SC kit come with larger fuel injectors or are the small stock ones enough with a recal? The stock exhaust on these 6.2's aren't much better than the old style logs (they aren't as nice as stock 496 manifolds). Wouldn't a free flowing exhaust offer a pretty good bang for the buck on a blown engine and also reduce combustion temps?
Don't get me wrong, I really would like to believe 15 mph can be this cheap and easy, but my concern is long term reliability. I want to hear from people that made this swap and have some run time!
Couple questions. What boost and what octane is required in your example to get 15 mph? These engines only hold 4.5 qrts of oil. Is a $140 cooler enough, or should you try an increase the capacity? Does the SC kit come with larger fuel injectors or are the small stock ones enough with a recal? The stock exhaust on these 6.2's aren't much better than the old style logs (they aren't as nice as stock 496 manifolds). Wouldn't a free flowing exhaust offer a pretty good bang for the buck on a blown engine and also reduce combustion temps?
Don't get me wrong, I really would like to believe 15 mph can be this cheap and easy, but my concern is long term reliability. I want to hear from people that made this swap and have some run time!
Whipple systems are tested and proved with stock exhaust so we know that works. Aftermarket exhaust, such as some inexpensive Imco's work great, they will lower the EGT's 50deg while lowering boost 1psi, power will be basically the same though (unless you change sc pulley for more boost). CMI and Lightning will make 25-30lbs of torque more below 4000rpm and will make a touch more hp (5-10), but will have the same temp/psi drop. So they do help, but many of our customers leave stock on and have no problem with that. You would have to decide bang for the buck on that.
To get 15mph in boat such as your is 6psi, 91 octane California gas, 4 pitches larger in prop.
Kits come with larger fuel injectors, adjustable fuel psi regulator, billet throttle body, intercooler, low temp stat, reflash, etc.
Dustin
08-25-2008, 09:37 PM
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The cooler I was thinking is from CP Performance, 2" H x 16" L. Works very well. The larger unit is $399.99 and certainly is better. The 16" will add over 2qts capacity which is enough, but the large unit is nearly 4qts extra capacity which nearly doubles the factory system.
Whipple systems are tested and proved with stock exhaust so we know that works. Aftermarket exhaust, such as some inexpensive Imco's work great, they will lower the EGT's 50deg while lowering boost 1psi, power will be basically the same though (unless you change sc pulley for more boost). CMI and Lightning will make 25-30lbs of torque more below 4000rpm and will make a touch more hp (5-10), but will have the same temp/psi drop. So they do help, but many of our customers leave stock on and have no problem with that. You would have to decide bang for the buck on that.
To get 15mph in boat such as your is 6psi, 91 octane California gas, 4 pitches larger in prop.
Kits come with larger fuel injectors, adjustable fuel psi regulator, billet throttle body, intercooler, low temp stat, reflash, etc.
Dustin
Whipple systems are tested and proved with stock exhaust so we know that works. Aftermarket exhaust, such as some inexpensive Imco's work great, they will lower the EGT's 50deg while lowering boost 1psi, power will be basically the same though (unless you change sc pulley for more boost). CMI and Lightning will make 25-30lbs of torque more below 4000rpm and will make a touch more hp (5-10), but will have the same temp/psi drop. So they do help, but many of our customers leave stock on and have no problem with that. You would have to decide bang for the buck on that.
To get 15mph in boat such as your is 6psi, 91 octane California gas, 4 pitches larger in prop.
Kits come with larger fuel injectors, adjustable fuel psi regulator, billet throttle body, intercooler, low temp stat, reflash, etc.
Dustin
Thanks a lot for the feedback. Our marina only has 89 octane (R+M/2 method in Missouri). What psi is safe to run using this fuel? I didn't know the small block kit comes with an intercooler. Sound's like a very nice package!
08-25-2008, 10:06 PM
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Just did a pair on a 28 ZX. They're 5.7's but same as the 6.2 kit. The systems are awesome and took about 7 hours for the first one and 6 for the second, including oil cooler install. The Bravo shift linkage and the computer have to be relocated, but other then that it is about as easy as swapping an intake and carb. Cutting the tape off the wiring harness to access some wires is the most time consuming part of the entire job. 
Just waiting on the computers and props and I'll let y'all know how it turns out! 
Just waiting on the computers and props and I'll let y'all know how it turns out!
08-26-2008, 07:22 AM
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Just did a pair on a 28 ZX. They're 5.7's but same as the 6.2 kit. The systems are awesome and took about 7 hours for the first one and 6 for the second, including oil cooler install. The Bravo shift linkage and the computer have to be relocated, but other then that it is about as easy as swapping an intake and carb. Cutting the tape off the wiring harness to access some wires is the most time consuming part of the entire job. Just waiting on the computers and props and I'll let y'all know how it turns out!
Just waiting on the computers and props and I'll let y'all know how it turns out! rhsj2006, sorry for the hijack, but I'm sure you are interested in this install as well!
08-27-2008, 12:02 AM
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Me 2! Dustin What kind of hp could be expected with your set up with Stainless Marine manifolds and risers on the 6.2? And do you have any hp & torque rpm curves? Steve
