How to get to 80 mph with a single screw

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02-23-2010, 04:24 PM

#11

dykstra

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PM Griff. He knows a lot about the 525SC.

Last edited by dykstra; 02-23-2010 at 05:39 PM.

02-23-2010, 05:20 PM

#12

blue thunder

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Quote:

Originally Posted by Old Navy

Race gas.

93 octane. I run 9.5:1 with hypereutectic pistons and up to 6.2psi with no problem, although I do have alum heads. Thats why I said 9.0. I would not go over 6psi with the 9.0 though. Not sure what the stock 525scs had for psi. The problem is the blower is a might small for a 454 and the higher compression helps a great deal and allows one to keep the blower rpm down so as not to make too much heat. Its a real good move with the 177 on a 454.

02-23-2010, 05:56 PM

#13

Griff

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A smaller top pulley on the blower and a BBlades labbed prop should get you there. No need to change the Tstat. Teague used to stock the 8# pulley which is about 2.75". You can still run 92 octane fuel and don't have to change anything else except for maybe the SC belt. Thats about all you can do without going inside the engine or adding a chiller.

02-23-2010, 06:07 PM

#14

blue thunder

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I have a couple 10 rib ~2.8" blower pulleys with the merc spline if you are shopping for some.

02-23-2010, 08:06 PM

#15

Rookie

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Quote:

Originally Posted by Kid Cumberland

Im running a stock 525SC setup and the boat tips out at 76MPH.

Is this on a GPS Speedo??? 6.9HP/MPH on a 95 straight bottom production boat sounds really good. or am I just off on my calculations.

02-23-2010, 08:38 PM

#16

getrdunn

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Quote:

Originally Posted by Rookie

Is this on a GPS Speedo??? 6.9HP/MPH on a 95 straight bottom production boat sounds really good. or am I just off on my calculations.

My old v24 Challenger was 5.3 HP/MPH however as you probably know they were one of the fastest production boats back then. That was a great bottom (slippery) but only about a 22 1/2 ft boat. Regardless I just think he wants to see 80 on the speedo.

Valako's comes out around 8 HP/MPH I think? I think the 525SC is over rated slightly also. Based on those numbers it would put this boat with a 525 at around 66 MPH. Never know maybe Reggie slipped a couple out with super sonic space age materials.

Last edited by getrdunn; 02-23-2010 at 08:44 PM.

02-24-2010, 08:27 AM

#17

ezstriper

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I agree with griff, smaller pulley(2-3 more boost) prop tuning will get you there if the 76 is GPS now..

02-28-2010, 09:50 PM

#18

Rebel_Heart

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It took my 93 27' Fountain about 650 hp to get to 80. And, that was doing nothing with the prop of drive height. But, I agree that if you are running 76 gps with 525, that pretty good.

03-01-2010, 12:59 PM

#19

Kid Cumberland

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Im surprised this didn't come up earlier. Yes it was 76mph on the GPS. Its a great running little boat. Im a pretty big fan of the 525SC but will give most of the credit to the hull design.