350 v 454. What's the best option for my situation?

[HunterRotten]

I know there is quite a big difference between 5.7 L of displacement and 7.4 L of displacement. Is the 7.4 L all that much more worth it over the 5.7 L?

My dad and I have now been working on this truck(1978 GMC SWB) almost every weekend and are doing a complete frame-up restomod in our garage with what we have and what's available to us. I currently have the motor my truck came with and a bare block 4 bolt main 350. There's also the fact that my exhaust was made to bolt up to a very nice set of heddman ceramic coated headers for a small block. I don't think accommodating the pipes for a big block is much of an issue but I am out a set of nice headers.

I'm not too worried about gas mileage, this truck is not and probably will not ever be daily driven unless the weather is nice and the humidity is down. I don't see it getting more than 3,500 miles a year if that and I don't think it's going to haul much more than furniture occasionally.

The information given, what would you say would be worth my while for an engine? The current 2 bolt 350, a ground up built 4 bolt 350, or an upgraded 4 bolt 454?

I'm not looking to blow my socks off and be stupid fast, I just want some fun low-end torque and to be able to cruise along like a happy camper.

[Rickysnickers]

If I was in your shoes, I would look at a 383. I think that would give you the best of both worlds. It would be "relatively" inexpensive and would give the mouse a nice boost in power.

[johnthegreat508]

I just did a 454 swap on my truck that used to have a pretty good runing 350 with vortec heads. My mild 454 has brutal passing power and roasts the tires. It sucks though for the most part, with the stock 16 gallon tank I can't drive past a gas station. The added weight of the 454 made my swb truck handle like a pig and feel a lot heavier. I would recommend staying with the small block. If you are building less than 500hp I would just build the 2 bolt main 350 and it will be plenty of fun. A stroker small block though would be the best of both worlds.

[3drburb]

I think the 350 may be the best bang for the buck in the long run of the 2.
I am guessing here, but was your truck a factory inline 6?
If so, on top of the big block 454 price you may also need a suspension upgrade to handle it.

[Redcap]

There is no replacement for displacement.

[andrewmp6]

Why not a ls swap it or a cummins swap ?The ls will give you almost big block power depending which one.A cummins 5.9 stock has 500 foot pounds of torque depending the year.

[b454rat]

I'm a big block guy, but in ur case a nice small block will be good. You can still bump up the power and have some fun and get drivability/mileage. When I swapped to a 454, I think my mileage got better cause the engine didn't have to work as hard. IMO, LS for mileage, not for power. Don't hold a candle to big block torque!!! Cummins would be too hard on the frame, would need to plate just bout whole frame to keep from twisting and cracking. Torque is lil over 400lb/ft for a rotary, going up from there. Plus added cost of tranny swap, mounts, crossmember, etc etc....

[my56chevytruck]

Originally Posted by Redcap

There is no replacement for displacement.

what are you wanting the 454 for? Looks, torque, potential HP, I chose BBC, the only way to go, but seriously, a 350 is good for driving but, if you want the looks, go with the 454. EVERYBODY has a 350, and there's nothing wrong with it, but if you want a different look and lots of them, go with the BBC. Like redcap said, there is NO replacement for displacement.

[Tiger Joe]

stick with a small block. you will have a lot less money into it.

if you go big block, not only do you need you headers, but you'll need just about everything else that would go on the motor too (fuel pump, front accessories, new rad). plus on top of that the cost to build the big block will probably be double the sbc.

don't get me wrong, i love the big blocks, got a 496 myself and my dad and I are doing a 468/nv4500 swap in a c30- BUT big blocks are a lot more expensive than small blocks.

buy a 383 crate motor, drive it for a few years with that, then later if you still want more think about a bbc upgrade

[Dead Parrot]

My 2 cents worth. Stick with one of the 350's. Sounds like you already have all of the auxiliary stuff for one(manifolds, linkages, brackets etc)

If you want low end torque, consider a rear gear change and add in some type of limited slip differential. Mate with a beefed up 700r4 if you want to avoid modern electronics or a newer overdrive if adding electronics ok. The overdrive will help keep the rpms down when highway driving.

Build one of the 350s for low to mid range torque. Towing type cam, cam timing, etc. Keep the 2nd as a spare or future build.

[77 C-20 Scottsdale]

I agree with what Rickysnickers said. Both my trucks are 454's, a C-20 and a GMC C-35. That being said, since you have a 1/2 ton short bed truck that will do relatively light hauling, I would build your 4 bolt main 350 block into a 383 stroker. All your accessories, exhaust, radiator etc, will stay the same. Much cheaper for you that way. You will gain a lot of power and still have a small block. Your original engine can be stored away, as you want to keep it if it is numbers matching to the trucks VIN.

[HunterRotten]

Thanks for all the information and opinions, everyone! There was a wide variety of opinions here from keeping my 2 bolt 350 to LS to even a Cummins swap suggestion. I am still on the fence about the decision but here is how I see it.

My 1972 2 bolt main 350 is a good engine (engine that's in the truck. Ran out of the factory with an inline 6) but it's a bit on the weak side. This is the cheapest route to go however if I go this route I'll always talk about an engine swap and drive myself crazy. I currently have to replace my alternate, power steering pump and a few other accessory items.

My 4 bolt main 350 would be really fun to build and a learning process for myself as I've never really dug into an engine. My dad used to build them for a living back in the 90's and early 2000's. This would be the most expensive option, whether it be a 350 or 383.

The 454 I have found is out of a 1982 1 ton and I am told it has about 115,000 miles. I am not looking for much more than a stock big block if I go this route. The seller is only asking for $500.

So at this point I'm leaning towards the 454 I think it would be a really cool engine to have since as said previously, everyone has a 350. I can swap over my MSD distributor, 660 Holley 4 barrel, and adapt my Chevy V6 aluminum serpentine brackets with adapters I found for about $150. + I'd have money from selling the ready to go 2 bolt 350. I am sure somebody wants it.

[Tiger Joe]

an 82 c-30 454 was probably only low 200s hp wise (i think maybe 230ish?). lots of torque but its going to choke out early in the rpm range most likely wont make it past 5,000 rpm.

IMO that's not ideal for a bbc in a half ton. plan on a cam swap to make it more fun.

plus don't count on the 350 selling very quick. I see small blocks on clist for months. heck ive got 3 sitting in storage

[HunterRotten]

Originally Posted by Tiger Joe

an 82 c-30 454 was probably only low 200s hp wise (i think maybe 230ish?). lots of torque but its going to choke out early in the rpm range most likely wont make it past 5,000 rpm.

IMO that's not ideal for a bbc in a half ton. plan on a cam swap to make it more fun.

plus don't count on the 350 selling very quick. I see small blocks on clist for months. heck ive got 3 sitting in storage

Yes, I agree. I did some research on the stock BBC. With the miles it has on it and peanut port heads I can see some upgrades while I clean it up. I'm thinking a camshaft of some kind and the seller said he has some 049 Corvette Heads but I know those BBC heads weigh a ton so I might be in the market for some aluminum heads which I would also do if I built a 350/383.

I also think I will replace my 2" drop coils with standard height coils + 2.5" drop spindles to counter the weight of the big block. I planned on upgrading coils as well as my truck is too low. All my suspension has been upgraded with tubular control arms, polyurethane bushings, and heavy half leaf's in the rear + caltracs flipped on the axle. I'm also going to be running a tremec tko 5 speed manual.

How much would you say a 2 bolt stock-ish 350 is worth? It's been cleaned up, sealed, painted and ready to go with new timing chain and harmonic balancer.

[3drburb]

If you are going with the 454, you may want to post on the suspension forum about your swap for advice before you do and mention your current suspension.

I looked at your build and with the new type A- arms and as low as you are now, I honestly think it's going to be way more than you plan for maybe even a rear end swap.

I know this is a truck ( build ) forum but sometimes switching out decent running gear and such especially when we are just getting in these trucks and cars can lead to many frustrations and stall projects.

In the end its your truck and cash but you asked for advice so this is my penny in the pot. Lol

Btw I saw your build and that truck is looking mean lowered with that black hood. You and your Dad is doing some nice work.

[Tiger Joe]

a truck engine could have 781s on it, which are very good heads ( I just bought an 85 454 out of a c30 and it was factory rated at 240 hp, came with 781s) 049 and 781 are very close and both good iron heads.

cheap aluminum heads will set you back close to a grand for a big block. the better brands are going to be over 2k.

your not going to make any power unless you change pistons cuz chances are that's a low compression motor. so no point in AL heads unless you bump the compression up.

I bought a 76 454 with 781s on it and it was like 8.25:1 compression based on what i calculated ( I checked everything before breaking motor down) it had a radical solid lifter cam in it and was a dog because it didn't have the compression to support the cam. other wise with low compression you cam choices are going to be limited, you'll likely end up with more a truck cam, nothing wrong with that, but since your building a half ton I'd think you want a lil more bark out of your motor.

so now if you are changing pistons well that's basically a full engine build. might as well save the 500 and build a 383 out of the small block you already have. now it sounds like you have your mind made up you want a big block. I get it. I've got a 496 in my c10 with a tko 5 speed. its a blast. if you want the big block do it, but just understand you are going to have to drop some coin into that 454, as the 80s era 454s were pretty gutless.

2 bolt 350? probably 2-300 bucks. There are at least a dozen 350s on my local clist. with these 350 crates selling so cheap, its really driving the used market down.

[tucsonjwt]

I have had both 454 and 350 in my 3 squares but they were all 3/4 tons. Your 1/2 ton truck is really not a good fit for a 454. As was mentioned, the truck 454 is not really a high horse engine - more for low end torque. If I were you, I would buy a nice 350 crate motor and be done with it. When you build up an old motor you have a lot of opportunities for mistakes and inappropriate parts (not that you would ever do that). I would sell what you have and invest that money in buying a used serpentine setup for your new crate motor.

The most important thing in your build up should be a transmission with a lock up torque converter (like 700R4 or newer.) I would make sure you have a rear axle ratio of no more than 3:73, and a 3:23 would be better. I know you don't care about gas mileage but if you have a nice truck you will be driving it more than you think. Plus, a relatively good fuel mileage old truck will be easier to sell when the time comes.

[SCOTI]

Buy a stroker kit for the 4-bolt 350 block you already have. Match the rotating kit w/the correct top end to yield the best investment returns.

It can yield the same power output of a mild big-block w/o the extra weight/costs. You'll be able to re-use most (if not all) of your existing components on the current 350 & you can continue driving the truck while building the new motor.

No need to do a BBC, LS, or Cummins swap for the power level you're seeking. Sometimes being 'different' is as easy as focusing on the details of what's already there vs the extreme of a swap.

[johnthegreat508]

I did higher compression pistons and have 049 heads on my 454 with better springs and a mild cam. The rebuild was pretty cheap because I ordered a complete kit from Northern Auto parts. As far as power goes, just build a 350 or 383 and throw a turbo on it, then you'll have as much power as you need.

[wilkin250r]

Personally, I'm not a huge fan of the early big blocks in stock form. All low-end grunt, but falls on it's face just as things start to get interesting. It's like a diesel engine on regular gas. But then again, I like to rev my engines out a bit. I would easily prefer a built 350 over a stock 454.

[akart]

Originally Posted by johnthegreat508

I just did a 454 swap on my truck that used to have a pretty good runing 350 with vortec heads. My mild 454 has brutal passing power and roasts the tires. It sucks though for the most part, with the stock 16 gallon tank I can't drive past a gas station. The added weight of the 454 made my swb truck handle like a pig and feel a lot heavier. I would recommend staying with the small block. If you are building less than 500hp I would just build the 2 bolt main 350 and it will be plenty of fun. A stroker small block though would be the best of both worlds.

vortec heads are junk. Lots of better heads out there. I am getting tired of this vortec on the brain stuff (said nicely). You need a new manifold,valve covers,gaskets, etc. And they have small valves. And it is a lot of work swapping out heads for old vortec heads which are prone to cracking. Just look around and see all the used heads which were bought to get a good set. Then you are going to have them rebuilt or you getting suspect "new"
I hates vortec. I guess misery loves company,

[nonstop]

Originally Posted by HunterRotten

My 4 bolt main 350 would be really fun to build and a learning process for myself as I've never really dug into an engine. My dad used to build them for a living back in the 90's and early 2000's. This would be the most expensive option, whether it be a 350 or 383.

The 454 I have found is out of a 1982 1 ton and I am told it has about 115,000 miles. I am not looking for much more than a stock big block if I go this route. The seller is only asking for $500.

Since you brought up cost, I will put in my two cents. My 85 3/4 ton came from the factory with a 350. When the time came to replace the engine, I decided to build a 454. I bought an engine for $600. I had a shop do the machine work, head work, and balancing, but I did all the assembly myself. With that said, when all was said and done, I was into the engine for about $6000 or more. It's not an outrageous build. It has a mild cam, and Edelbrock performer intake, and .030 over pistons. What really pushed the price up, was the parts that did not come with the engine and were not interchangeable with a small block. It still sounds like he would be money ahead building a nice stout 383.

[WorkinLonghorn]

The best combination I ever had was a 350 with a major RV cam and a jetted QudraJet. I don't know the cam specs because I bought it like that from a guy pulling a TT. It must have been the most radical available and it was a kick to drive. It was all finished by 4500 RPM (guessing) but it sure was fun.

[HunterRotten]

There has been quite a lot of feedback here and I have read everything that has been posted. I appreciate all the information everyone has shared! There is a bit of confusion I see in terms of where my truck is at but I think that's my fault for not clarifying.

Suspension is a bit unknown. I plan on lifting the front end up as it is too low. I have 2.5" drop spindles I plan on keeping on the front, making the coils the determining factor (and of course the engine.) The rear end as of today has 4+1 leaf springs, rated for 1950 lbs each with caltracs. The spring has been flipped under the axle for a drop.

Drivetrain. I had fabricated driveshaft made at a local shop that will connect my Tremec TKO 500 5 speed manual to my GM 12 bolt. I have a open differential with 3.42's and will for some time.

Engines in question:
A 1972 dated 350 2 bolt main. It has been built as far as I can tell however it has been built with stock equivalent parts. It's history is unknown, when I bought the truck in 2015 the oil the came out of it was scary. When I took it apart though it looked pretty good. It has an aluminum intake, new MSD distributor, and holley 660 street avenger. The heads on it are pretty good, I think we decided they were better than the vortec heads we have.

197? dated 350 4 bolt main. Bare block that's in rough shape, needs some machine work. We have some pistons and a camshaft for a 350 laying around.

1982 dated 454 4 bolt main. Seller says 115,000 miles. Comes with everything from the oil pan to the cast intake. For an extra $300 he will give me 094 heads to accompany it. I plan on using my MSD distributor and holley 660 street avenger 4 barrel carb with it. Probably change out the intake to an aluminum one.

This all being said. I have told the seller I am interested in the 454 with the 094 heads for $800 pickup on Saturday morning about 2 hr away. This will get me the big block I'm drooling over and I think I can make it fit my needs for less than $1,000 ontop of initial purchase.

If I'm wrong or backwards then call me out on it and tell me why. Worst case scenario when I put my truck back together (it's in more pieces than I can count) I'm not happy with my big block and I can save my pennies for awhile and build my bare block that'll be waiting.

[Tiger Joe]

Like I said in my last post- you have your mind made up on the big block and that's fine. Just say that.

$1000 into a big block? I'll say you go over that- headers, intake(stock truck iron is not a good intake) and you need a cam swap. There's your $1000 easy.
are those heads ready to go or need machine work? Any machine work is going to cost probably $3-400 minimum.

115k is getting up there in mileage for a 80s carb motor so I wouldn't be surprised to open that motor a find you need a full rebuild. Remember cars back then didn't go 200 or 300k miles like modern ls engines.

even after all this, like I said in my post you still have a low compression motor and will likely choke out before 5k rpm. I used to own a 454ss- the 90s factory built big block half ton. I'll tell you a low 200 hp big block is NOTHING like a 70s muscle car big block. If that is the big block you are after a truck motor won't cut it.