Offshoreonly.com - 525 EFI clone

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Quote:

Originally Posted by Griff (Post 4095900)

Much easier and less expensive to build a hopped up 500EFI clone.

502 GM Block
GM Rect port heads with some port work and Manley valves
Use a 500EFI intake and MEFI 4
GM forged crank
Manley rods
JE Pistons
Cam similar to a 525EFI cam(Crane 741 on a 114 lob sep) and matching springs
I would work with Bob M and duplicate something he has already spec'd and something that somebody already has an ECM tune for.

I would not use 525EFI heads as it limits the exhaust you can use and increases the price.
You could go to Dart Pro 1 heads or AFR's to boost the HP some more.
The 500efi intake is only good to about 600hp before it becomes a limiting factor.

Thats pretty much what i would be after. Not really concerned with wringing every last hp out of it as i know the intake sets the limit there. I really just like the looks and the reliability of the system and with the intakes that pop up regularly think i could build a good pair for the Scarab at some point in the future. OffshoreDrillin Rob had (i think) MGD Performance in MD do his 500 EFI w/AFR's and some other stuff. I think they were in the low to mid six hundred HP range. I guess i should have worded this thread differently as a "500EFI clone with added HP" as i kinda knew the 525 was a different animal. :cool:

Griff you are a warehouse of knowledge :D which AFR's btw?

Tell ya something else i like about the EFI's . . . .you can throw a towel across the tops of the intakes and lay on 'em to work on the boat :D

315-335cc depending on the cam and overall package and the desired goals.
Might want to use the 315's for more torque down low and at cruise rpms or use the 335's for more hp up top

I think that the intake manifold and throttle body are a key part of the 525. I'm also liking the intake system on the new 565 a lot. Full length headers are a must for scavenging. Dual mechanical & electric fuel pumps and fuel cooler are another interesting part of the package. Must be able to run on 87 octane. I have to disagree on using ported GM heads. When you can buy a very low hour 525 take-out for $20,000 I think that it would be hard to duplicate this engine for that amount. As pointed out earlier there are all of the bolt on pieces like pulleys, high output alternator, high output steering pump, raw water system, fuel cooler, p/s cooler, oil cooler, headers alone are 4-5G.

Do not forget about the Brodix heads. There flow numbers do not show as well but in actual application they work Very well. Best horse power is in the heads and easiest on the engine.

Hey KWright any info on the wilson manifold you used(part number /cost). looking to go the same route on a 525 efi i am rebuilding.

Sorry been gone. My phone wouldn't let me post. There are all kinds of options best thing to do is to give Tim Hogan a call. Great people to work with.

Hi KWright ,
i want send you a PM but your box is full.
Please clear your box....
Have left you a visitor massage.
Thanks

Cleared. Sent you a email let me know if you need anything else.