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-   -   convert 454 to 525sc (https://www.offshoreonly.com/forums/general-q/202915-convert-454-525sc.html)

blue thunder 02-10-2009 04:13 PM

I have 2 tstat housings that came with that I don't use if you are needy.

BT :cool:

jeff1000man 02-10-2009 05:11 PM


Originally Posted by blue thunder (Post 2797291)
I have 2 tstat housings that came with that I don't use if you are needy.

BT :cool:

I know someone that would probably buy them from you if you want to sell them. If you are interested PM me and I'll get you his number.

redcorvetteman3 02-10-2009 09:40 PM

454
 
So if I already have good parts in a 496 about 9.5 or little less comp I can bolt on a 177 or 250 blower and gain a 100 hp+ or? I thought most people think those blowers are two small.

jeff1000man 02-10-2009 09:43 PM


Originally Posted by redcorvetteman3 (Post 2797646)
So if I already have good parts in a 496 about 9.5 or little less comp I can bolt on a 177 or 250 blower and gain a 100 hp+ or? I thought most people think those blowers are two small.

Thos blowers are to small for a big engine. They work pretty well on what you are trying to do. Run 3-4lbs from a 177 and there is no reason you shouldn't be over 600HP

chris-jack 02-11-2009 02:10 AM

thanks for the offers, i think i will do the conversion after i have been driving the boat. it is winter, i had no chance to go with it till now. i want to see how the thing works and decide afterwards if i will do the upgrade. here in austria the boating seasaon starts not before April and i just want to do the exhaust, nothing else. thank to everybody.

blue thunder 02-11-2009 06:17 AM


Originally Posted by redcorvetteman3 (Post 2797646)
So if I already have good parts in a 496 about 9.5 or little less comp I can bolt on a 177 or 250 blower and gain a 100 hp+ or? I thought most people think those blowers are two small.

The work very well with a little higher compression. Mine is 9.5. It crutches up the blower so you get a decent effective compression ratio without overspinning (heating) the blower. Mine is about 12.5:1 at full boost (5psi) and runs on 93 octane. Hypereutectic pistons too. I wouldn't attempt this with FI though, only the carbed version due to tuning ajustability. Also you should put in cometic head gaskets, inconnel exhaust valves and arp head bolts.

BT :cool:

Griff 02-11-2009 12:24 PM


Originally Posted by redcorvetteman3 (Post 2797646)
So if I already have good parts in a 496 about 9.5 or little less comp I can bolt on a 177 or 250 blower and gain a 100 hp+ or? I thought most people think those blowers are two small.


I would go with a 250 on 496ci. With your CR, you will just have to keep boost around 4#.

jeff1000man 02-11-2009 12:28 PM

I got a 250 blower set up for a single carb and I have the carb and all the belt and bots and flame arrestor you can have for $2500 plus the freight also. Carb needs rebuild, but it came from nickerson.

redcorvetteman3 02-11-2009 06:05 PM

454
 
So generly a 177 or 250 up to say 540 ci ? Then maybe a 420 for 572 and up? Sounds like a good price on your package , but I need two then probibly new head gaskets (only got felpro now) then new roller cam and lifters and then better exhaust . Im pushing 10-12k would love to do it but wont see it in the boat buget for now. Oh what about inner coolers would i need them two? Thanks

jeff1000man 02-11-2009 06:29 PM


Originally Posted by redcorvetteman3 (Post 2798306)
So generly a 177 or 250 up to say 540 ci ? Then maybe a 420 for 572 and up? Sounds like a good price on your package , but I need two then probibly new head gaskets (only got felpro now) then new roller cam and lifters and then better exhaust . Im pushing 10-12k would love to do it but wont see it in the boat buget for now. Oh what about inner coolers would i need them two? Thanks

It all just depends on what you want overall.

I have put the 250's n 540's buut it really doesn't do anything until it is at WOT, but then it also depends on the cam and the heads etc.

I have also put 8-71's on 454's to run 6-7lbs.
It is all in the set up.

The 420 is still only good up to a 502 or 509 also, but it depends on the setup. I have seen 420's on 540's that make 900HP. I have also seen 10-71's on 540's that only made 850HP.

Save up your money and by then you might have other options available. Better to save the money and get everything at once, or what happens is that needs and tech change with prices or availabilty and you don't need the stuff you have been stockpiling. Parts are a lot easier to buy than to sell.


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