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superchevy.com built a 400hp SBC for $1000


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http://www.superchevy.com/technical/engines_drivetrain/completebuilds_testing/sucp_0910_chevy_350_engine_build/index.html

 

I am hoping for some input from people who are experienced with engine building. I was wondering if this is actually possible or did they doctor the results just to give the article a happy ending. Per the article they got 407 hp at 5,900 rpm and 410 lb-ft of torque at 4,500 rpm; if this is true this is incredibly good value for money.

Edited by logan1
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I will say yes this is do-able within that described budget. Friends can have parts, Barter, swap meet, ebay, and Craigslist are all ways to save money. But I would think, to make that engine last. Most people would start with hot tanking the block, new cam and lifters, all engine bearings, pistons and so on. Which will of course, cause that budget to go North.

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If you have the block and heads already then yes. alot of the time people get on the "might as well go big" boat and go with a $700 set of forged pistons, $600 rods, $1500 crank, $900 heads..etc when people have made the same power level safely on cheaper cast pistons, stock rods with ARP bolts, cast crank..etc.

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I'd believe it.

 

A "refreshed" bone-stock 350 can get you close to 250hp. I thought I went "all out" on my build and it didn't go much more than $2300. If you shop around you can get SBC performance parts for cheap. I got my forged steel crank for less than $400 brand-new. I'll probably be pushing something like 400~420 at the flywheel.

 

This downturn in the economy sucks for the industry but it's a goldmine for the consumer if you've got the cash.

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http://www.superchev...uild/index.html

 

I am hoping for some input from people who are experienced with engine building. I was wondering if this is actually possible or did they doctor the results just to give the article a happy ending. Per the article they got 407 hp at 5,900 rpm and 410 lb-ft of torque at 4,500 rpm; if this is true this is incredibly good value for money.

 

Logan1:

 

Yes it is doable IF a Fuel Injected 350 engine with a good bottom end, compression and oil pressure can be found. Without this it WILL NOT BE DOABLE for $1000.. Further, with a Carb for induction, the short block will go down hill at an accelerated rate. If fuel injection is used and proper oil changes, then the short block will last LONGER.

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Logan1:

 

Yes it is doable IF a Fuel Injected 350 engine with a good bottom end, compression and oil pressure can be found. Without this it WILL NOT BE DOABLE for $1000.. Further, with a Carb for induction, the short block will go down hill at an accelerated rate. If fuel injection is used and proper oil changes, then the short block will last LONGER.

 

 

You make it sound like a carb is the devil. There is no difference between the fuel injected small block and carbed one. Plus carbs are cheaper and they wont make your "short block decay at an accelerated rate". Yeah if your a retard and use don't tune it it will make the thing run pig rich but a little know how will make a huge difference. 400 horse for a grand is not outside the realm of possibilities if you spend your money wisely. A good carb, intake, ported heads, cam, and headers will make 400 pretty easy. All of that can be had for less than a grand if you know to where to look.

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Logan1:

 

Yes it is doable IF a Fuel Injected 350 engine with a good bottom end, compression and oil pressure can be found. Without this it WILL NOT BE DOABLE for $1000.. Further, with a Carb for induction, the short block will go down hill at an accelerated rate. If fuel injection is used and proper oil changes, then the short block will last LONGER.

 

LMAO......How did you come to this conclusion?

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Yes it is doable IF a Fuel Injected 350 engine with a good bottom end, compression and oil pressure can be found. Without this it WILL NOT BE DOABLE for $1000.. Further, with a Carb for induction, the short block will go down hill at an accelerated rate. If fuel injection is used and proper oil changes, then the short block will last LONGER.

 

I'm trying to figure out how fuel injection makes a cast-iron block, steel crank, rods and cast pistons last longer than a properly tuned carburetor? I understand the argument that fuel injection, to some extent, makes power more efficiently, but it also costs more to purchase and modify.

 

If you can find a wrecked 1998+ F-Body or Corvette and someone who desperately needs it off of their front lawn, you could get extremely close to 400hp for around $1000, I suppose. Or, maybe find a chop shop in TJ? Then again, that's not a "traditional" small-block, it'd be an LSx.

 

I do see lots of ads on Craigslist for performance longblocks (some come fairly dressed but, typically, less carb, manifolds, water-pump, pulleys, etc.) for at or less than a grand. Might want to look there.

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You make it sound like a carb is the devil. There is no difference between the fuel injected small block and carbed one. Plus carbs are cheaper and they wont make your "short block decay at an accelerated rate". Yeah if your a retard and use don't tune it it will make the thing run pig rich but a little know how will make a huge difference. 400 horse for a grand is not outside the realm of possibilities if you spend your money wisely. A good carb, intake, ported heads, cam, and headers will make 400 pretty easy. All of that can be had for less than a grand if you know to where to look.

 

The Carb is the DEVIL. They take a LOT more maintenance than a good Fuel Injection System to keep them in good condition. Typical TBI injected 350 engines from the junk yard have MUCH less wear than the carb'd 350 engines with the same mileage. The carbs tend to wash down the cylinders with raw fuel especially on start-up. Typically if the choke system works properly on the carb, then one pump on the gas pedal usually sets the choke to the proper position when COLD. This shot of RAW fuel will tend to wash down cylinder walls on at least one cylinder. Multiple pumps on the gas pedal just make the situation WORSE. It is surprising the comments to the former post on this subject and the number of negative responses to same.

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If you have the block and heads already then yes. alot of the time people get on the "might as well go big" boat and go with a $700 set of forged pistons, $600 rods, $1500 crank, $900 heads..etc when people have made the same power level safely on cheaper cast pistons, stock rods with ARP bolts, cast crank..etc.

 

No offense, and its totally off topic, but if one spent $2800 on the rotating assembly and $900 on heads in an effort to make n/a power he is doing it all wrong.

 

As for the 400hp 400ci for $1000 is quite do able if one is resourcefull enough. If you are not very resourcefull just spend 4 or 5 times the money on a crate motor with a warranty. Thats what I would do.

Edited by roger280zx
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Deal-making is a subtle art, and I don’t doubt that savvy shoppers, with a dose of sprightly do-it-yourself enthusiasm, can arrive at a 400 hp engine for under $1000. As with most things, tenacity, cleverness and a dash of good luck will trump a fat wallet.

 

But any decrement of skill/experience/patience, and you’re looking at more money for less performance. “It can be done†is not to be conflated with “it’s straightforward to do for the average amateurâ€. You can easily spend $10,000 and end up with only 250 hp… and eaten cam lobes after 20 miles of driving.

 

Personally I think that $500 for a mostly-complete 350-based SBC is a good deal. Even if the engine eventually grenades or fails to meet desired performance specs, it’s an excellent placeholder until something better arrives. Building a custom engine using new parts is the only way to ensure trouble-free operation, and even that is contingent on good skill and good luck. But then you’re looking at $500 pistons, $600 rods, $1300 heads,… Then there’s the machining: $150 for tanking and leak-checking the block, $200 for boring and honing with torque-plates, $250 for balancing the crank/damper/flywheel, $200 for align-boring the mains, $200 for decking the block, and so forth.

 

So why not just buy a crate engine? Because the crate engine likely has a flat-tappet cam (with specs not to your liking), cheap rockers and pushrods, cheap oilpan and so forth. And has anyone on this board ever successfully collected on a warranty for a non-stock-replacement crate engine?

 

Bottom line: experienced people who know the weak-links can afford to take shortcuts and therefore can save considerable money. The rest of us need to be realistic about the alternative: top-shelf parts for mid-shelf performance.

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That is pretty close to my combo. I used a TPI motor with iron vortec heads, a Performer RPM intake, edledbrock carb, decent matching cam. Everything else stock, my car makes a tick over 300rwhp on the dyno. Not too shabby for a super low cost combo.

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The carbs tend to wash down the cylinders with raw fuel especially on start-up. Typically if the choke system works properly on the carb, then one pump on the gas pedal usually sets the choke to the proper position when COLD. This shot of RAW fuel will tend to wash down cylinder walls on at least one cylinder. Multiple pumps on the gas pedal just make the situation WORSE. It is surprising the comments to the former post on this subject and the number of negative responses to same.

 

In a fuel injected vehicle, unless you're talking about late-late-model EFI (like after MY2000), you would still get a cylinder wash-down at cold start up. As the "choke" mechanism functions essentially the same on a TBI as it does on a carb. If anything, I'd think you'd end up dumping more fuel by it running from a pressurized injector than it would from the almost non-existent vacuum draw on a cold engine. It wasn't until they had computer controlled timing advance/retard mechanisms that would cause the engine to run leaner when cold (to warm up the engine faster and prolong the life of the catalytic converter) that much changed. Plus, I'd think for the sake of engine life, you'd want it to run a little rich at start-up, no?

 

I'm far from an expert, but what you're telling me sounds counter-intuitive.

 

They take a LOT more maintenance than a good Fuel Injection System to keep them in good condition.

 

Because chasing down bad sensors is less maintenance than checking balance with a uni-sync and a screwdriver? To me EFI presents more points of failure, with a carb you have one low pressure fuel pump and like 2 (3?) vacuum lines, with EFI you've got a whole mess of vacuum lines, 5 sensors, injectors, fuel rails, two pumps and a computer.

 

Don't get me wrong, a well-planned, thoughtfully installed EFI system works better on average than a comparable carburetor, but I don't see how (unless you're talking about the newer OBDII systems with 3D maps) it really makes much of a difference on engine wear over a carb. If you live on a mountain at 5000 ft. and commute to your work at sea-level, then yeah, probably.

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Fuel injection is really cool and the tuneability is really amazing even using a stock GM ECU but not every motor needs to be injected. A properly tuned carb is just as good as a properly tuned injection setup. Carbs are cheaper and the tuning one is a really simple matter if you can turn a screwdriver. Fuel injection is also easy to tune provided you have the right mindset it has the disadvantage of being more expensive and electrically complex. Too say one is better than the other is foolish, however neither one has anything to do with the durability of the motor. You are trying to make it seem like a carb dumps grotesque amount of fuel every time you open the throttle. It just isn't the case, granted you have to pump it once to set the choke. Big deal, look at the cranking PW of an injector and see how much longer it is than at idle.

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Fuel injection is really cool and the tuneability is really amazing even using a stock GM ECU but not every motor needs to be injected. A properly tuned carb is just as good as a properly tuned injection setup. Carbs are cheaper and the tuning one is a really simple matter if you can turn a screwdriver. Fuel injection is also easy to tune provided you have the right mindset it has the disadvantage of being more expensive and electrically complex. Too say one is better than the other is foolish, however neither one has anything to do with the durability of the motor. You are trying to make it seem like a carb dumps grotesque amount of fuel every time you open the throttle. It just isn't the case, granted you have to pump it once to set the choke. Big deal, look at the cranking PW of an injector and see how much longer it is than at idle.

 

Over the RPM range of the engine, the Carb will have rich and lean curves. The screwdriver can only set the IDLE fuel mixture. Granted EFI is more expensive than a Carb. But EFI is tunable, both Fuel and Ignition, THOUGHOUT the RPM range. With Carbs the main jets need to be changed with changes in Barometric Pressure and Humidity to achieve optimum mixture burn. EFI continually uses feedback from the exhaust to adjust fuel mixture for optimum quality throughout the RPM range.

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Thanks for posting the article. Although I am taking my own path that involves a bit more cleaning and replacement of higher wear items, I share a very similar build mentality. My dad and his friends made alot of HUGE contributions to my build that will likely keep my total SBC conversion somewhere around $2000-$2500.

 

Being in no rush to finish a project and having a well defined budget seems to be the best circumstances for saving money.

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Over the RPM range of the engine, the Carb will have rich and lean curves. The screwdriver can only set the IDLE fuel mixture. Granted EFI is more expensive than a Carb. But EFI is tunable, both Fuel and Ignition, THOUGHOUT the RPM range. With Carbs the main jets need to be changed with changes in Barometric Pressure and Humidity to achieve optimum mixture burn. EFI continually uses feedback from the exhaust to adjust fuel mixture for optimum quality throughout the RPM range.

 

There are standalone ignition systems that would allow you to program advance curves, they're not that expensive, either, which means that if you can spend a little time jetting and setting the carb, you could dial in an appropriate ignition curve to match.

 

Barometric pressure and humidity changes have to be pretty drastic before you need to change the main jets. I'm sure if I drove my car from Miami, FL to Las Vegas, NV I would start seeing the outer limits of serviceability with whatever jet size I started with, but the engine would still run and I don't think I'd spin a bearing because I got a few extra aerosol-sized-droplets of fuel in the combustion chamber.

 

The fact of the matter is that with a budget of $1000, I don't think you're going to find anything more than a TBI set-up. For a fully integrated, super-amazingly-extra-efficient, tunable EFI system you're going to be looking for something like a sequential multi-port. TPI might be a cheaper, yet effective, alternative.

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Now that's a more realistic magazine engine build! These guys bought some nice parts, spending $1800 for some ported AFRs (vs. the $600 Vortecs installed originally)... to lose 18 ft-lb of torque at 3500 rpm. Folks, this is exactly what happens in the real world. Sometimes we cut corners with massaged stock/cheap parts, and the combo works wonderfully. Then we get excited over the possibilities, "upgrade" (at high cost) and end up with inferior results.

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Michael: They lost torque in the low-end in exchange for a "peakier" power band. I wouldn't call that "inferior" results, I'd call it tuning.

 

Not everybody wants to melt their tires at a stop-light. Personally, I'd want my power-band to be just above where I might be cruising on the freeway. Another guy that does AutoX or road-race might favor a higher RPM performer.

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