525SC Weiand 177 On A 454 MAG in Formula 242LS
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525SC Weiand 177 On A 454 MAG in Formula 242LS
I have a the factory mercruiser supercharger and manifold off a 525SC engine. Is there any difference between this and an automotive Weiand 177? I want to run it on my 88 242LS Formula. The boat has the 454 MAG bone stock with 200 hours. Can I just bolt it on with a 1050 dominator and a set of stainless marine headers? It looks like the 525 is basically a 454 MAG with a supercharger any other differences? I see the compression is lower I'm assuming thats pistons? Is the head gasket and studs the same? Also anyone have a 10 rib crank pulley for sale? Thanks.
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I have a the factory mercruiser supercharger and manifold off a 525SC engine. Is there any difference between this and an automotive Weiand 177? I want to run it on my 88 242LS Formula. The boat has the 454 MAG bone stock with 200 hours. Can I just bolt it on with a 1050 dominator and a set of stainless marine headers? It looks like the 525 is basically a 454 MAG with a supercharger any other differences? I see the compression is lower I'm assuming thats pistons? Is the head gasket and studs the same? Also anyone have a 10 rib crank pulley for sale? Thanks.
#4
Don't confuse the 525sc with the new 525. 525sc was a 454 with a blower on it. I think it was a 6-71, but I have been out of the I/O scene for a while.
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The upper pulley shaft on the Merc 177 has a different spline than the automotive 177 so Merc customers could not put smaller pullys on to raise the boost and increase warrenty claims.
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I have a the factory mercruiser supercharger and manifold off a 525SC engine. Is there any difference between this and an automotive Weiand 177? I want to run it on my 88 242LS Formula. The boat has the 454 MAG bone stock with 200 hours. Can I just bolt it on with a 1050 dominator and a set of stainless marine headers? It looks like the 525 is basically a 454 MAG with a supercharger any other differences? I see the compression is lower I'm assuming thats pistons? Is the head gasket and studs the same? Also anyone have a 10 rib crank pulley for sale? Thanks.
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You can put smaller pulleys on those. Mercury called them high altitude pulleys and they were also
available aftermarket. We had them on a trip 42 Fountain
available aftermarket. We had them on a trip 42 Fountain
#9
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As was said, the auto and marine SC's are the same except for the shaft for the pulley. Merc used a splined shaft and they are NLA.
There are also 2 different types of pulleys with different depths that were used for the upper pulley on the Merc SC.
I would try to find a slightly smaller pulley for the lower crank pulley to reduce boost. You might be able to order a new lower pulley. I think the stock Merc upper was 3.5" and the lower was 7"....or it was 3.25 and 6.5. Either way it was 2:1 overdriven and was 5.5# of boost. With your higher compression, it would be smart to reduce boost a little and use a 1/2 inch smaller lower bring boost down 1/2-1# and make it about 1.85:1 overdriven. You should be fine with a V8-24 ignition module and should be able to run the stock 32* of timing.
The 525SC was hand assembled and balanced at Merc Racing. Different pistons, cam, roller rockers and a lot of other little stuff that are different from a 454mag.
There are also 2 different types of pulleys with different depths that were used for the upper pulley on the Merc SC.
I would try to find a slightly smaller pulley for the lower crank pulley to reduce boost. You might be able to order a new lower pulley. I think the stock Merc upper was 3.5" and the lower was 7"....or it was 3.25 and 6.5. Either way it was 2:1 overdriven and was 5.5# of boost. With your higher compression, it would be smart to reduce boost a little and use a 1/2 inch smaller lower bring boost down 1/2-1# and make it about 1.85:1 overdriven. You should be fine with a V8-24 ignition module and should be able to run the stock 32* of timing.
The 525SC was hand assembled and balanced at Merc Racing. Different pistons, cam, roller rockers and a lot of other little stuff that are different from a 454mag.
#10
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Teague used to carry smaller upper pulleys that could increase boost to 8#. Not sure if they still do. I was running just under 8# of boost on my 525SC with no problem at all.