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Most HP out of a 525

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Most HP out of a 525

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Old 02-13-2019, 08:37 PM
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Default Most HP out of a 525

Just curious whats the most HP you have seen out of a 525 without using a supercharger or turbos? I went down to bare blocks and am almost done putting them back together with some goodies. Dyno runs will show if it was work it or not

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Old 02-13-2019, 10:18 PM
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We found really good gains with the 525 just by going to a big bore. With no other modifications other than a 4.600 bore and ECM tuning to correct air/fuel we picked up approximately 60hp over a stock 525. Final number on the dyno was 610hp. Stock 525s constantly make 550hp on our dyno. By no means claiming to be the highest number from a 525 but we were very happy with the gains

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Old 02-13-2019, 10:28 PM
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Originally Posted by tdbrickndirt View Post
Just curious whats the most HP you have seen out of a 525 without using a supercharger or turbos?
I stopped reading after this because you clearly don’t like to party.
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Old 02-17-2019, 07:04 AM
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Originally Posted by MDG_Jason View Post
We found really good gains with the 525 just by going to a big bore. With no other modifications other than a 4.600 bore and ECM tuning to correct air/fuel we picked up approximately 60hp over a stock 525. Final number on the dyno was 610hp. Stock 525s constantly make 550hp on our dyno. By no means claiming to be the highest number from a 525 but we were very happy with the gains
Thanks for the reply. My motors went on the Dyno Thursday. They’re now 514ci. New heads, bigger valves, stiffer springs, better rocker arms etc. 657.2HP at 5750rpm and 641tq at 5000rpm. This was with a carb setup so when I put the efi intake back on the numbers will orobobe a little lower. Going to need to tune ecm like you did. Unfortunately I need new headers as fell so this rebuild is going to cost more than I was hoping lol
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Old 04-03-2019, 07:51 PM
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Did you ever re-dyno after the EFI was reinstalled?
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Old 04-04-2019, 10:07 AM
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The 525 intake runes out of air flow in the low 600hp range. Opening the mouth helps but its restrictive in other places. I did build mine last year made them into 540's opened intake and cnc heads stock cams and dyno 620 hp. But the motors gained a lot of torque. I gained 7 mph over stock 525's in a 42 Fountian.
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Old 04-04-2019, 10:19 AM
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Pic from Mark Rinda at MER Performance in SC:


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Old 04-04-2019, 10:24 AM
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Old 04-04-2019, 10:32 AM
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Originally Posted by rvtransport View Post
I gotta say, I love seeing “blue power” in colors other than blue. I wish more folks would have opted for that upgrade. I always wanted to build a pearl white 37AT with one red motor and one blue one.
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Old 04-04-2019, 10:38 AM
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a 525 is a 502.............lets stay in line folks.....
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