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Current power: 7.4l mpi motors (oval port heads, 310hp and MEFI 3's)

NOW?!?!

I am planning on building motors and robbing as many accessories and brackets from the old motors as possible. Upgrading what I have to as I go. I also have HP525 EFI intakes laying around, which I would love to use. Looking to burn 89 to 91 octane.

Option #1: Take current blocks to be tested and make them into 489's or 496's, good set of heads, cam and use the 525 intakes.

Option #2: Get 502 long blocks, change the cam and use the 525 intakes.

Option #3: Find myself 502 blocks, turn them into 509's and use the intakes. And have the capability of turning into 540's later.

Option #4: This is what my plan was until now(after reading about so many builds), build 540's with some (525 intake massaging).

End goal...

89-91 octane
use the HP525 intakes(which I understand are the limiting factor)
looking for 550-675 HP and rpm range of 5400-6000

thanks guys
 

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Current power: 7.4l mpi motors (oval port heads, 310hp and MEFI 3's)

NOW?!?!

I am planning on building motors and robbing as many accessories and brackets from the old motors as possible. Upgrading what I have to as I go. I also have HP525 EFI intakes laying around, which I would love to use. Looking to burn 89 to 91 octane.

Option #1: Take current blocks to be tested and make them into 489's or 496's, good set of heads, cam and use the 525 intakes.

Option #2: Get 502 long blocks, change the cam and use the 525 intakes.

Option #3: Find myself 502 blocks, turn them into 509's and use the intakes. And have the capability of turning into 540's later.

Option #4: This is what my plan was until now(after reading about so many builds), build 540's with some (525 intake massaging).

End goal...

89-91 octane
use the HP525 intakes(which I understand are the limiting factor)
looking for 550-675 HP and rpm range of 5400-6000

thanks guys
You asked for my thoughts so you will get them. If I were in your shoes your budget would dictate a bunch. If funds were available I would do it this way. I would go with aftermarket blocks and build 540's with good heads and use your intakes that you like. The extra cubes will make it easier to hit your power target and still have a smoother idle to make it easier on the drive going into gear without having a rough idle. If purchased right the cost of the short block would be close to what buying 502 short blocks would be, but with better parts. Buying a 502 block vs a dart or bowtie (or similar) will not be a big spread in cost, so going with the better block now will mean less cost down the road. With the variety of heads out there you can get a great head package that will be a great match for your combo and your intake and tuning will finish them off.

Now if you are limited on funds then using your current blocks and throwing stroker kits in them is a great way to get cubes and get an improvement. Truth be told, if your short blocks are in good condition you could put good heads and cam in them your performance boost would be very noticeable and you would not have the huge hit to the pocket book that new complete engines would do. A new top end could comfortably put you in your 550 + hp window, so that is something I would think about. I have lots more thoughts, but no time so let us know what you think.

Paul
 
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