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'72 Monte Carlo, 454 bbc, Sniper EFI and Hyperspark ignition, 4:11 TH400
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Discussion Starter · #1 ·
Hey folks. I bought my first classic and I'm ready to upgrade the engine. It is a very stock 454 that has the Sniper EFI and ignition on top. Stock headers are hard to look at. Stock intake also an eye sore. Especially painted silver. It has a slight knock with 25k miles, but runs smooth and is quick with the 4:11 rear end. It also has the GearVendors overdrive. Anyhow, I'm curious what direction you would go first. Heads and headers? Headers and intake?
 

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Yeah a slight knock would be my number one priority as to finding out what it is, a ticking fuel pump, rod or main bearing out? Before I worried about the intake manifold I’d be on the knock source.

Bogie
 

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Craigslist 5.3 complete with 200k for $500
Frash ecm $150.
Sbc to LS swap brackets $50

Bolt it up and Running for $800(you have the other stuff already).

If you want to make power just add money. But you can (usually) make the same power easier with a 5.3 then you can with a 454 for the same cash.
 

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5.3 makes more power than a 7.4 with better flow potential in the head options?
Yes. A 5.3 has potential to be built for the application. It is a strong block that can take a good amount of abuse.


Some info in stock and aftermarket head options in the link below. This does not discuss porting and customization which a book could be wrote about. But this is a easy to read overview.




He is talking about a 454 with aftermarket heads running 9.5 compression. Lets call it 420hp and a optimistic 530 ft/lbs that will cost 3 to 7k.
If you take a junkyard 5.3, swap a cam, put on some factory heads, and run a bit of boost you can make similar if not better numbers with better driveablity and longevity.

When it does go your not out 5k and 3 months of build time.
You hit up Craigslist, find another shortblock, throw a cam in, and your running the next weekend for less then $1000.

By using factory stuff you avoid a good amount of downtime. If you want ported heads(lookup playing with factory heads and the results a bit of work gives nice results) etc you can have a backup set sitting on a shelf ready to go in case you drop a valve when 7 decides it has had enough.
 

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'72 Monte Carlo, 454 bbc, Sniper EFI and Hyperspark ignition, 4:11 TH400
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Discussion Starter · #8 ·
I should have mentioned I want to keep the old 454 in this equation. I totally understand taking the route of newer is better in every way, but the 454 is a classic and one of the best. Like the TH 400 tranny behind it. One of the best ever built.
 

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I dont see how a 5.3 with boost can compare to a 7.4 with similar boost? You are not very good at math. Best flowing ls heads flow around 400 cfm compared to over 500 cfm for best rat heads.
ideal head/ street boost 5.3 would make over 900 hp.
same formula for 7.4 with slightly less boost 1100 plus hp
 

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Hey folks. I bought my first classic and I'm ready to upgrade the engine. It is a very stock 454 that has the Sniper EFI and ignition on top. Stock headers are hard to look at. Stock intake also an eye sore. Especially painted silver. It has a slight knock with 25k miles, but runs smooth and is quick with the 4:11 rear end. It also has the GearVendors overdrive. Anyhow, I'm curious what direction you would go first. Heads and headers? Headers and intake?
I am cheap. So I would start with some(inspected) 236, 49, or 781 heads(whats probally sitting on there now), mild cam, and go from there with 500ft/lbs as clos to 3500-4000 as possible. The lower you can move that peak torque the more often you will hit it. It will make for a nice streetable engine that won't break the bank.

What heads does your 454 have?
 

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I dont see how a 5.3 with boost can compare to a 7.4 with similar boost? You are not very good at math. Best flowing ls heads flow around 400 cfm compared to over 500 cfm for best rat heads.
ideal head/ street boost 5.3 would make over 900 hp.
same formula for 7.4 with slightly less boost 1100 plus hp
The 5.3 doesn't compare. The BBC will be cubic $'s more unless you want 5-700HP with boost. After that the BBC needs new everything to withstand much of anything. With that in mind, once those parts are upgraded, then BBC is hands down a winner in the HP category. It's not hard to make 1000hp with a turbo'd big block if you have alot of do re me.


If the OP wants to keep the BBC, then big headers, better heads is the way to go for ground thumping torque numbers that are very street friendly - to a point.
 

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A good start is to find out what the ticking noise is? Know that BBC's are real hard on flat tappet cams. You may have a cam with a lobe going bad. A easy way to check is with the Vavle covers off take a yellow or white marking pen and make a straight line lengthwise on each pushrod, about one inch long. You can use some rags so you don't make a mess. start the engine and look for the pushrods rotating. if one is not rotating, you will find the rocker arm is probebly not tight because the cam is going flat.
Could be a lot of other things, Fuel pump, Rod bearing, Wrist pin, ETC. Tto check for a rod or wrist pin, with the engine running. start pulling plug wires and reconnecting them, when you find the one that changes the noise, you will know which cylinder it is. Good luck on your project.
 

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a good hyd roller cam, duel plane intake, headers, carb and you're on your way to 450+. As far as cam goes, Call Straub or Bullet and get their recommendation.
I'm running a std bore stock piston 1978 454, with a Hyd roller, Morel lifters, Harland Sharp rockers
• Adv. 288/300 .050" 229/241
• Lift 600/570 with 1.7 109 Lobe Sep
RPM Air Gap intake
Hooker Blackheart headers
Holley 870 (Merlin Hardcore modified)
and i'm just shy of 500hp / 515 tq
 

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Only use a hydraulic roller cam for a BBC.
eBay heads are OK, but have a shop check them over closely. Or just buy the Racerite heads from Brodix.
 

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'72 Monte Carlo, 454 bbc, Sniper EFI and Hyperspark ignition, 4:11 TH400
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Discussion Starter · #18 ·
Only use a hydraulic roller cam for a BBC.
eBay heads are OK, but have a shop check them over closely. Or just buy the Racerite heads from Brodix.
Which Brodix heads would you bolt on? I definitely want aluminum...
 

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JP at the beginning you did not mention you want a big HP engine? Now you want aluminum heads?

How much power do you want to build??? Then we choose after market aluminum heads!
To be practical keep power below 1.5hp/cubic inch, so 460 x 1.5 = 690 or much less or much less? You only need a 265 cc open chamber oval port from AFR or look at Chad Spieir heads in similar 265 cc range. Those 2 heads are the best heads in that size/power range. If you only need 550 hp then GM 049/781 heads prepped by someone that does port work can get you there easily. The GM heads are cast iron so keep CR below 9.7:1
 

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'72 Monte Carlo, 454 bbc, Sniper EFI and Hyperspark ignition, 4:11 TH400
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Discussion Starter · #20 ·
I had no idea cast iron heads could get me to 500hp. I think I need to identify what heads on are already on this! Do you know where the numbers are located on heads?
 
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