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boss27 10-22-2008 03:25 PM

building a 454
 
would like to build a strong 454 it is a mag dont care if efi stays on or not. would like
intake
carb
heads
cam
headers
the bottom end is good now so i dont want to touch that this winter would like to see 600hp? or close? is this even possible?
please dont recomend a 540 or some thing bigger as i can not do that at this time! price range of $6-8000 any help,thoughts, ect would be great!

jayhawk261 10-22-2008 03:47 PM

600 hp out of a 454 will be tough without going to high compression. If it is a stock mag now, it probably has 8.8:1 compression. With the components you listed above (the right ones), and your stock compression, you would probably be limited to the 500 - 550 hp range max.

All of the items you listed will run about $6k - $7k total just for the parts. The headers are pretty expensive as I'm sure you know, and a good set of heads with springs and valves will run about $2500.

On top of the parts cost, you'll have some money in R&R unless you have the ability to do it yourself. I don't know if you can do a cam change in the boat. I know in mine, I thought I could because the vertical part of the back seat lifts with the engine hatch. Upon closer inspection, the engine sits low enough that the cam is still below the opening and wouldn't be able to be removed in the boat. Just some things to think about.

We went through my 454 MAG MPI last year and got 501 hp with raising the compression to 9.5:1 and doing basically what you've talked about here. I kept the fuel injection, which will be leaving soon. I'm switching to a carb because the stock manifold is too restrictive.

ezstriper 10-22-2008 05:29 PM

I agree with jay there.....thats a far reach without a blower and keeping the compression in the real world area, also to run that much cam going to be a issue..just don't see it working well...Rob

boss27 10-22-2008 05:59 PM

thanks for the imput guys, i think i might be better off with a pro charger....but i am not sure of ecm re-flash, herd lots of bad stories on re-flashes that simply did not work!....just ask jasonsmith on this!

blue thunder 10-23-2008 05:07 PM

I agree going forced induction is your best and cheapest option. Install good exhaust valves, cometic head gaskets and run carbs not injection. That's what I would do. I never dynoed my engines but believe I am close to 600hp with 454s and 177s.

RBeyer 10-23-2008 05:21 PM


Originally Posted by blue thunder (Post 2723445)
I agree going forced induction is your best and cheapest option. Install good exhaust valves, cometic head gaskets and run carbs not injection. That's what I would do. I never dynoed my engines but believe I am close to 600hp with 454s and 177s.

I have a ProCharged and modified 454 Mag FI. I can give you some input if you would like. I have a set of heads that are built and ready to bolt on 1.94 2025 Iconel valves, etc. $1000. I opted for Edelbrock Aluninum this time, I'm not sure they were worth the investment we saw some gain and of course the weight thing but not enough for the investment. As far as the Cometics I am torn after 250 hours I did have a failure O-ringed this time. I had Tyler Crocket dyno and reflash. I would not do it without being on a dyno again. I ran good for 250 hours but the dyno tune made a huge differance. 720 HP 727 ft lbs and turn key every time. 1998 Velocity 280 with a B-max 1.30 ratio 97.8 MPH GPS.
Bob

boss27 10-23-2008 07:05 PM

rbeyer that is a heck of a top speed! what fuel system did you use? headers? cam?.....here's what i think i am going to do.for this winter headers@ a pro charger. this should put me around 620hp!.....again thanks for all the imput!

HaxbySpeed 10-23-2008 09:53 PM

1 Attachment(s)
I just put this one together from spare parts.. 8.7-1 comp,
Edelbrock RPM Oval ports, stock 525SC cam, Used 177 from 525SC, 4.75 - 5lbs boost, CMI E tops from 500EFI. Not bad power for a pretty cheap top end package.. :drink:

RBeyer 10-24-2008 06:03 PM


Originally Posted by boss27 (Post 2723523)
rbeyer that is a heck of a top speed! what fuel system did you use? headers? cam?.....here's what i think i am going to do.for this winter headers@ a pro charger. this should put me around 620hp!.....again thanks for all the imput!

My apologies typo 87.8 GPS Aeromotive fuels system, 60 lb injectors custom fit to the rail and intake by Tyler, EMI Thunder exhaust, Procharger M3SC, It is a custom grind cam I can get you the specs. I have a perfect Crower custom grind and those heads I spoke of for sale. If you Procharge I would at least look at those items and would Dyno. Speeking from my lessons. Also you probably want to consider a drive upgrade. It is the week link.

the vig 10-25-2008 08:17 AM

I know you dont want to hear about a larger engine, but I just sent out a deposit to Bill Lawson at Ateco. He is building me 540 form pan to manifold for $8995.00 Comes with a 2 year warranty and he will put it on the dyno after we reuse my Ignition, Carbs Pumps etc.. and make sure it is making 600 HP


995.00 is not to much more of a stretch for some peace of mind.

IMHO

Also he has been great about answering all my newbie go go fast boat questions and is seems to be happy to spend enough time on the phone with you to make you feel comfortable about working with him.


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