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Old 09-30-2024 | 10:08 AM
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Default 454 build criticism or opinions

So now that I have decided to put a big block back in my Bandit, let me know what you guys think of the potential build. The goal is to get the most out of what I have to work with already on the garage.

Brodix 312cc bb2 plus rec ports
22cc dome.030 pistons
Upgraded rods with tarp hardware
Hardin Marine Cam
Imco thumper exhaust
Edelbrock RPM Air gap
Quick fuel 750

Only other option I have is running mild ported 049 iron heads with 2.19/1.88 valves.

This will replace the peanut port 454.
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Old 09-30-2024 | 04:50 PM
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A 454cid engine will most likely run better/stronger and you'll probably be happier with the results of the GM 049 castings vs a 312cc intake runner head.
Either way, you'll also be happier with using a dual-plane intake manifold (Edelbrock Air-Gap if you can) on a 454cid engine too. 👍
Just my .02
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Old 09-30-2024 | 05:57 PM
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The rpm air gap I already have along with both heads. But it's for the rec ports. I do however get so many mixed opinions on heads.
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Old 09-30-2024 | 06:19 PM
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I would try to swap the manifold with someone and go with the 049 heads. Guys have used the rectangular port intakes on oval port heads but it is not ideal. I agree that the Brodix heads are too much for a 454.

I would not waste my time and money putting ARP bolts in stock rods. By the time you are done you can almost buy a set of new Scat or Eagle rods and be better off.

The only problem with the 049 heads and the pistons you have is you are going to end up with too much compression for pump gas. I dont like to see any more than 9.5 to 1 with cast iron heads, prefer a little less. Thats with 93 octane fuel.

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Old 09-30-2024 | 06:31 PM
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Originally Posted by BillK
I would try to swap the manifold with someone and go with the 049 heads. Guys have used the rectangular port intakes on oval port heads but it is not ideal. I agree that the Brodix heads are too much for a 454.

I would not waste my time and money putting ARP bolts in stock rods. By the time you are done you can almost buy a set of new Scat or Eagle rods and be better off.

The only problem with the 049 heads and the pistons you have is you are going to end up with too much compression for pump gas. I dont like to see any more than 9.5 to 1 with cast iron heads, prefer a little less. Thats with 93 octane fuel.

I have scat rods already with the arp bolts. I just neglected to mention it since they're just an I beam rod, nothing special other than the bolts.
I thought that the 049 heads were 122cc? Am I wrong? (Lots of conflicting info on the be web)
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Old 09-30-2024 | 07:37 PM
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Originally Posted by BillK
I would try to swap the manifold with someone and go with the 049 heads. Guys have used the rectangular port intakes on oval port heads but it is not ideal. I agree that the Brodix heads are too much for a 454.

I would not waste my time and money putting ARP bolts in stock rods. By the time you are done you can almost buy a set of new Scat or Eagle rods and be better off.

The only problem with the 049 heads and the pistons you have is you are going to end up with too much compression for pump gas. I dont like to see any more than 9.5 to 1 with cast iron heads, prefer a little less. Thats with 93 octane fuel.
I usually try to stay around 9.2 with iron heads solely because you can never trust the fuel you get to be the octaine advertised and I dont like being too close to the edge just to gain a couple horsepower.
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Old 09-30-2024 | 07:46 PM
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Originally Posted by Danimal182
I have scat rods already with the arp bolts. I just neglected to mention it since they're just an I beam rod, nothing special other than the bolts.
I thought that the 049 heads were 122cc? Am I wrong? (Lots of conflicting info on the be web)
Most of the ones I have seen are closer to 118. If they actually are 122 then you will probably be ok. Only way to know for sure is to cc one of them.
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Old 09-30-2024 | 07:59 PM
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Originally Posted by Danimal182
The rpm air gap I already have along with both heads. But it's for the rec ports. I do however get so many mixed opinions on heads.
Heads are one of of those things that are all over the map of opinions and suggestions.

But you can't escape physics.

What rpm are planning to cruise at?

What peak HP are you loosely looking to achieve?

049 heads will have better port velocity at part throttle cruise, but will likely limit the top end a little.

Brodix 312 are aluminum? I couldn't fine mention of iron versions. The Brodix heads flow way more in the exhaust, as well as intake. 312s are not as big as the GM 088 Rec Ports that Mercruiser used on many of their Blue engines, and they have really poor int port floors and stifling exh port flows.

049 exh flow @0.400" 140cfm
088 ported exh [email protected]" 188cfm prob best 088 flow
Brodix 312 plus exh [email protected]" 187cfm
​​​​
The Brodix are the way to go. Better intake flow and way better exh flow. You're getting about 265 cfm @ 0.400".

Stan Weiss' - Cylinder Head Flow Data at 28 Inches of Water -- DFW / FLW Flow Files for use with Engine Simulation Software

You can use Larry Meaux's head flow chart to check them out.
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Old 09-30-2024 | 08:38 PM
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What are the specs on the Hardin Marine Cam?

Did I miss what drive you have on the Bandit?
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Old 09-30-2024 | 10:50 PM
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Originally Posted by Danimal182
Brodix 312cc bb2 plus rec ports
22cc dome.030 pistons
Upgraded rods with tarp hardware
Hardin Marine Cam
Imco thumper exhaust
Edelbrock RPM Air gap
Quick fuel 750
I like it. Cam specs would be helpful. I'll always opt for better performing aftermarket aluminum heads than stock iron.
I run Dart Pro1's at about 320cc on my 454's @ 585HP and 87 pump gas.
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