Can you make a 502 mpi flow more air?
11-18-2014, 09:57 PM
#12
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I have a ported 502 mag upper and lower will support 650 hp or your money back .will require upgraded injectors ,I would sell it reasonable knowing it would go to a good home and your old intake has value .was on a 540 alum heads big cam flashed stock ecm
11-19-2014, 07:33 AM
#13
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It would be cheaper in the long run to enjoy as is and work on finding some better intakes so when you have to do some freshening, you can upgrade and make the power you want. For 500HP, they are just fine with some light mods. Much after that, they are a waste of money for NA application in my opinion. They have proven time and again to not do well after 5,200RPM and now a days 5,500-5,700RPM or more seems to be the norm for guys making good power. I have read every post on every thread on every boating forum regarding MPI intakes over the last 10 years and the results have been the same for everybody that tried to make power NA, they spend a ton of time and money modifying the lower, the throttle body and the fuel rail and then they dump them for something that works.
11-19-2014, 08:40 AM
#14
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If I wasn't supercharged,I wouldn't have bothered w/ mine.but I wanted injectors in each port.this back in 05 and no intake was available.
If I was NA,I'd go the route I did for my truck,Holley single plane and a 1000cfm throttlebody.Used that setup for a few hot rod engines ranging from 454 to 509's.
If I was NA,I'd go the route I did for my truck,Holley single plane and a 1000cfm throttlebody.Used that setup for a few hot rod engines ranging from 454 to 509's.
11-19-2014, 09:43 AM
#15
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I've been down the highly modified MPI system road. Yes it can be done, but it ended up costing about the same as when I ditched it and went with the Holley HP setup. That opens up soooooo many more options and horsepowers and is much easier to deal with.
When working with the MPI, every time you turn around you are making a compromise somewhere. I still have the modified MPI setup gathering dust on my shelf. My setup was looking to be ~600-620 hp on a 540.
If I had done it again, I would have just rebuilt my perfectly good 502 MPI and set it up for boost. Much easier and would have been cheaper but then again I never do anything the easy way. I wanted something different from the norm.
When working with the MPI, every time you turn around you are making a compromise somewhere. I still have the modified MPI setup gathering dust on my shelf. My setup was looking to be ~600-620 hp on a 540.
If I had done it again, I would have just rebuilt my perfectly good 502 MPI and set it up for boost. Much easier and would have been cheaper but then again I never do anything the easy way. I wanted something different from the norm.
11-20-2014, 11:44 AM
#16
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I made 650 hp from my low compression 540 thru a modified mpi intake with bored out throttle body with my blower belt off. Keep in mind how ever this was on Crocketts dyno with no accessorys and he used the more generous J607 correction. I still have a spare bored out throttle body for one that I would part with, Smitty
11-20-2014, 04:00 PM
#17
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I have 540 ci engines with stk heads making 509 hp at 5100 rpm's the boat runs 93.2 at 5000 rpm's. The boat is worth more with merc. factory fuel injection at 93 mph than with any after market blower or efi. system at 100 + mph.
I know the cheep way with a intake and carb and a different cam and I'm at 625+ all day.
I thought I read some where that a guy opened one up to flow more air some how.
I know the cheep way with a intake and carb and a different cam and I'm at 625+ all day.
I thought I read some where that a guy opened one up to flow more air some how.
11-20-2014, 04:07 PM
#18
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14 Apache. Steve Stepp is a old family friend and I never thought of owning anything other than a velocity. I also know how to make them run 39 feet 9000# 500efis. 5 blade 27 hydro's 88 mph. But now I don't feel guilty. He doesn't own velocity anymore.
11-20-2014, 09:24 PM
#19
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Ignoring the laws of diminishing returns does not discount its existence
The mag mpi intake will never be sexy ,if your mpi set up is in good shape swapping to a modded one will be one of the cheapest components of a journey well into the mid to upper 500 hp as rigged ,wet exhaust and all .after that its time for stroker crank ,blower ,more rpm or combo of all of above . Now that I have read the last post I realize your already there .if you were nearby I would hand you the ported upper and lower I have to let you try it .did well on a 540 gen 5 with a cam and gil exhaust and Russ Collins injectors
The mag mpi intake will never be sexy ,if your mpi set up is in good shape swapping to a modded one will be one of the cheapest components of a journey well into the mid to upper 500 hp as rigged ,wet exhaust and all .after that its time for stroker crank ,blower ,more rpm or combo of all of above . Now that I have read the last post I realize your already there .if you were nearby I would hand you the ported upper and lower I have to let you try it .did well on a 540 gen 5 with a cam and gil exhaust and Russ Collins injectors
