502 chevy vs 350 chevy

[64nailhead]

1st, and most importantly ( 🙂 ), I'm always going to push the turbo aspect of any power adder build because I'm a bit partial to them. But there are some reasons for that. The concern of having too small of a head or cam is easily overcome with a turbo. And actually, it is what makes a turbo build be so much more streetable than an equivalent HP NA, nitrous or supercharger build. You can drive the vehicle , daily drive, without using any boost implying no additional fuel needed due to using a relatively mild cam and set of heads. Then figure in the parts cost. A turbo build will be half or less than half of a supercharged or blower build. 565 mentioned using quality, name brand WG's and BOV. I agree, but 2 38mm Tial wastegates and 50mm Tial blow off valve is going to run you about $8-900. Add in two $300 turbos, another 3-400 in manifolds and piping and you're into it for about $2K of hard parts. Compare that to a blower or supercharger. I agree that a cam swap for the BB turbo build would be recommended, but you'd have to do the same for an equivalent NA, blown or supercharged build.

The cons to the turbo build is definitely the packaging. But it can be done and that aspect of the build doesn't cost anything.


To each his own, and don't let me or anyone else talk you into anything that you don't want. Build the car to do what you want it to do. For us (son and I) that has always included being able to drive whatever we build (during the non-salt seasons). Everything we put together is comfortable to ride in, has inner fenders and requires very little additional maintenance. The bulk of the additional maintenance is taking the time to check over all of our mods (welds, wiring and potential leaks.) If we can't hop in it in the summer and go for a couple of hundred mile cruise then it's not what we want. Turbo builds fit that description - at least for us.

Good luck - Jim

 

[bob64]

1st, and most importantly ( 🙂 ), I'm always going to push the turbo aspect of any power adder build because I'm a bit partial to them. But there are some reasons for that. The concern of having too small of a head or cam is easily overcome with a turbo. And actually, it is what makes a turbo build be so much more streetable than an equivalent HP NA, nitrous or supercharger build. You can drive the vehicle , daily drive, without using any boost implying no additional fuel needed due to using a relatively mild cam and set of heads. Then figure in the parts cost. A turbo build will be half or less than half of a supercharged or blower build. 565 mentioned using quality, name brand WG's and BOV. I agree, but 2 38mm Tial wastegates and 50mm Tial blow off valve is going to run you about $8-900. Add in two $300 turbos, another 3-400 in manifolds and piping and you're into it for about $2K of hard parts. Compare that to a blower or supercharger. I agree that a cam swap for the BB turbo build would be recommended, but you'd have to do the same for an equivalent NA, blown or supercharged build.

The cons to the turbo build is definitely the packaging. But it can be done and that aspect of the build doesn't cost anything.


To each his own, and don't let me or anyone else talk you into anything that you don't want. Build the car to do what you want it to do. For us (son and I) that has always included being able to drive whatever we build (during the non-salt seasons). Everything we put together is comfortable to ride in, has inner fenders and requires very little additional maintenance. The bulk of the additional maintenance is taking the time to check over all of our mods (welds, wiring and potential leaks.) If we can't hop in it in the summer and go for a couple of hundred mile cruise then it's not what we want. Turbo builds fit that description - at least for us.

Good luck - Jim

First Thanx for the input. I honestly like the idea but l know nothing about turbos, an l'm a old dog so it's not so easy to change my thought process. Second is l'm Canadian an as so a part that cost $15 dollars in States cost $147 here(AC Delco emergency cable) which is insane for the same brand. So l did order it from States and got all 3 cables delivered for half of the cost of one up here. So a turbo system availability l either have to drive a hour or so or order and wait. Not big issue, but still a factor. Nothing really around Niagara, and the shops that are here you still have to order it in. So simple is sometimes not what you want but it's the best way to go.

I have looked into it an a twin turbo system isn't cheap here but a 144 supercharger is close.

I know when l was thinking about EFI system on the camaro it took 6 months to get all the parts together an l did it because l thought it would be interesting, but it's not really, just a costly up-date. I only drive the car maybe 100 miles a year, boring! So when l built the olds l threw the left over parts from the camaro on that BB, intake, Carb and heads. Don't really drive it either.

So now it's this 502 or 350. I could rebuild a 78 350 for whatever system or build a top end for the 502, or stuff either the 72 350 or 502 as is in the Monty.

To complicate it more l got a 67 Chevelle that's been on the back burner for 6-7 years, which needs engine, transmission an rearend depending on how it's build.

So many parts laying around l'd like to use them up before l have to buy. But when building any vehicle l have found if you add one part odds are you'll need buy other parts to go with it. Just a brain twister!!

 

[1badgbody]

Leave the 305 in and drive it til it dies. Stroke the 350 with forged internals while you're cruising the car with the 305. I have a few cars with strokers and a few with 305s. Nothing wrong with a 305 (throw a 420/443 lift cam in it). Get in turn the key and drive with 0 problems, great reliable engine. I've had plenty of big block guys tell me that my small blocks are cute asking when I'm going to put a real engine in my car. Coming in at 1-1.5 sec faster in the 1/8 seems to wipe the smile off of their face. Stay small block. No mods to the car, parts are cheap and easy to find.

 

[Turbolq4]

Twin turbos on that big block.......



Over 1000lb/ft.

That's plenty of reasons for me!!

 

[bob64]

Leave the 305 in and drive it til it dies. Stroke the 350 with forged internals while you're cruising the car with the 305. I have a few cars with strokers and a few with 305s. Nothing wrong with a 305 (throw a 420/443 lift cam in it). Get in turn the key and drive with 0 problems, great reliable engine. I've had plenty of big block guys tell me that my small blocks are cute asking when I'm going to put a real engine in my car. Coming in at 1-1.5 sec faster in the 1/8 seems to wipe the smile off of their face. Stay small block. No mods to the car, parts are cheap and easy to find.

Sorry but l wouldn't waste a cent on a 305SB in less l absolutely had too. Ok not 100% true as l built an 78 Elcamino for one of my kids an put in a 305Vortec. But wouldn't do it for me if there is other choices.

Stroking a 350SB is a possibility, it's a cheap route.

 

[bob64]

Twin turbos on that big block.......



Over 1000lb/ft.

That's plenty of reasons for me!!

Yes, yes an No. Can't seem to wrap my brain around Turbo's, while l understand the concept an total free HP/TQ, in reading about doing a Turbo build it isn't something that l am comfortable doing myself. But in saying that it is still a possibility with an if l can find a kit that's a direct throw on an go.

I think some phone calls are in order to a Turbo manufacture an see what they come up with in a direct kit.

 

[Turbolq4]

Yes, yes an No. Can't seem to wrap my brain around Turbo's, while l understand the concept an total free HP/TQ, in reading about doing a Turbo build it isn't something that l am comfortable doing myself. But in saying that it is still a possibility with an if l can find a kit that's a direct throw on an go.

I think some phone calls are in order to a Turbo manufacture an see what they come up with in a direct kit.

Getting a kit is going to be big money. If you can weld at all then you can make a hotside for the turbos. It's the management end (wastegates and EFI/carb/ignition) that are the challenging part of turbos.

 

[kw502bbc]

I picked up a 87 Monte Carlo SS cheap last fall, 305 Sb, 200R4, 373 single tire fire 7.5, l do have a posi unit that came with the car. The car has T-roof also which is a negative as far as l'm concerned.

In saying all that l have the choice of a 502 with 450hp/550tq or 350 with 350hp/?tq. The 305 that's in the car seems ok but?
Also have the choice of transmission, 200R4, 400 or 4L80E.
Rearend will be getting an up-grade to a 9" that's laying against side wall in shop.

As some of you might know l'm into BB's, Camaro is 496, Olds is 468.

So my issue is them dam T-roof's, if l put a BB in it the twist l feel is going to cause issues. If l go 350SB then everything such as transmission(200R4) and 7.5 can stay.

Its going to be just a street car no racing, just nice cruiser. Don't really want to brace the snot out of the frame.

So thoughts on what you would do is the question? I need a little push in some direction as l'm on the fence.

 

[kw502bbc]

Unless you really have to have a Big Block, the 350 would be the way to go. The 502s are great engines, make tons of torque, and run well on pump gas. The motors have large bores with siamesed cylinders, so they are harder to cool. The iron head ones are heavy, too. The engines actually started out as motors built for Mercury Marine, so they have premium internals.

 

[lilbowtie]

Only you can really decide which way makes more sense for what you want to do. I run a stock block L-82 w/ chevy iron 2.02 heads and it's pretty respectable.