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Old 11-30-2016, 10:03 AM
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Originally Posted by Baja8808
I will be .030 over, so I think 8.8:1 with .010 in the hole and .053 head gasket. I have daytona sensors ignition boxes, can I still use the 525sc curve at that compression?
I dont know where i got the .060 overbore. Didnt get my coffee. In yet. But yea, 4.280 bore will be slightly less.

You could use the stock 525sc map, or a custom 2d map, or 3d map, etc. Lots of options
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Old 11-30-2016, 04:27 PM
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I played with timing from 31* to 34* all in. My motor made the best power at 34* and also had the lowest EGTs. My builder did not want to run more than 34* though.
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Old 11-30-2016, 04:41 PM
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Stock 525sc ran 34 or 35, cant remember. I'm running 35* at 6000rpm, 34* at 5500RPM, 32* at 5000RPM. 468, 420 blower, 8.5-9lbs boost. -9 heat range plugs, non projected tip. EQ 320 Iron heads.
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Old 11-30-2016, 05:37 PM
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The stock timing is 35 at 4500.
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Old 12-01-2016, 06:48 AM
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the pair i did have the t bolt 4 with v6 modules and 34 deg total advance.they have a custom race tek piston.the combination of parts seemed to work out well.
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Old 12-01-2016, 07:22 AM
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Only thing Id be wondering , is the use of the intercooler with this setup. The 177 is gonna be small for a hot 454 with good heads and cam. If i recall, on the engine mike tkach is talking about , those blowers were at 115% overdrive to make about 5lbs on my old engines and the ones hes built (my old blowers). They didnt have intercoolers.

I know when i added the intercoolers under my 420 blowers, i had to really increase the overdrive to get the boost back. The core is an airflow restriction. I am assuming you will have to go with a pretty small upper pulley, just to get to 5psi on that setup. Prob still better than not having an intercooler at all though on that setup.

Couple things Id consider. Making sure you have enough carb, so your not handicapping the blower. They dont like to have inlet restriction. The 177s are not teflon tipped, and i would make sure the blower is tight and fresh. If the rotor to case clearance is excessive, this will further exacerbate the issue.

Also, keep an eye on the rear bearings. The rear of those blowers use a crankcase, and known to get fuel diluted when the seals wear.

With that being said, i dont think 650hp will be too hard. Should be a nice running setup.
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Old 12-01-2016, 08:56 AM
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if i remember correctly we were at 4 to 5 lbs boost.the carbs were singel 1025 cfm 4150s.joe brought up a good point about the rear bearings on the 177s,,they do need to have the lube freshened every now&then.
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Old 12-01-2016, 09:05 AM
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Originally Posted by mike tkach
if i remember correctly we were at 4 to 5 lbs boost.the carbs were singel 1025 cfm 4150s.joe brought up a good point about the rear bearings on the 177s,,they do need to have the lube freshened every now&then.
Sounds about right. I wanna say, it had a 7 inch bottom pulley, with a 3.25 top , but its been a while . Prob would need a 3.00 or 2.85 top pulley with the chiller to get to about 5lbs with the cam and head upgrade
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Old 12-01-2016, 01:03 PM
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I have a 7 inch bottom pulley and a 2.85 top pulley. The blowers are going to DMPE for rebuilds. The carbs are the 1050 dominators.
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Old 12-01-2016, 02:37 PM
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^^^ nice . Heard good things about Darren
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