What are Bore, Stroke, Porting, and Relieving?

You hear car guys throw around the terms, “bore” and “stroke” all the time.  Most of us don’t know what that means.  I do.  Here’s what they mean, and how to identify them.

Bore:  Cylinder bore is the measurement of the diameter of the cylinders in an engine.

Stroke:  Stroke is the amount of movement a piston can move up and down.

A bored engine happens when you machine out the block.  For example, taking a 400 cubic-inch Chevy V-8 and boring out the cylinder walls to make the engine displace, say 500 cubic inches.

A stroked engine is simple to build.  You just pull out the current internal moving parts, and put in bigger ones.  Because bigger is better.  An infamous example of this is Chevy’s 302 cubic-inch V-8 from 1967-1969.  Chevy took their garden-variety 283 cubic-inch V-8 engine block, and put the bigger 327 cubic-inch V-8 internals in.  Voila.

An easy way to put into perspective just how thirsty an engine can be is to remember that a 302 cubic-inch engine will theoretically inhale and exhale 302 cubic inches of air and fuel in two revolutions of the crankshaft.  If you punch that engine out (slang for stroking it) to 347 cubic inches, then you’re going to have a more powerful engine.  That 347 stroker engine is popular with drifters – it’s based off of Ford’s capable 302 cubic-inch V-8.  A 347 cubic-inch engine is 14.9% larger than a 302.  So, that 350 horse 302 will have 402 horsepower.

Just stroking an engine for more power won’t solve your problems entirely.  A cam (or more nowadays) pushes on the intake and exhaust valves.  If you’ve got a bigger crankshaft and pistons, upgrade the cam!  You’ll have a far more reliable engine.  Upgrading the cylinder heads is also smart.

The nice part about stroking an engine is that the engine remains the same size externally.

Porting:  A ported engine refers to enlarging the intake and exhaust ports of an engine.  This makes for better and more airflow.

Porting is common in drag racing, especially with the use of nitrous oxide (yes, the same stuff that is used to push out whipped cream from the can).  It just makes more room for the air to go in and out.

Relieving:  No, the engine is NOT using the bathroom!  That would be relieving itself.  A valve seat is where the valve is attached to.  It’s usually a small mound of metal, but it doesn’t need to be.  Relieving just removes the extra metal to make more room for bigger valves.

Here are some pictures of the different kinds of engine enlarging.

This is a bored Chevy big-block V-8 engine block.  It’s been bored out from 454 cubic inches to 489 cubic inches.  That’s 35 cubic inches more air and fuel this engine will hork down.

This is a stroked Chevy small-block V-8 engine.  It displaces 383 cubic inches, rather than 350.  Instead of 350 horsepower, it makes 425 horsepower.  You can buy this engine from Summit Racing.

This is a close-up of a beautifully-ported Ford 302 cubic-inch V-8 from a 1987 Mustang GT LX 5.0.  The larger port is the exhaust port.  The small hole is the valve seat.

This is a relieved Ford 221 cubic-inch flathead V-8.

 

Why Legislation A.B. 550 Matters to Car People

California has recently proposeda new legislation.  While that might not mean all that much to us, it should.  Legislation A.B. 550 would allow for the owner of a motor vehicle subjected to the rigorous California smog check program to pay a $200 smog abatement fee instead of having to go to the trouble of smogging the car.

This bill would require the payment to go to the Air Quality Improvement Fund.  The measure will be considered by the Assembly Transportation Committee.

Currently, the smog check program requires an inspection of all motor vehicles when the car is initially registered, then biennially upon registration renewal, transfer of ownership, and various other circumstances.  You can find all of that on the DMV’s website.

The law currently exempts all cars manufactured prior to 1976, and certain other vehicles.

What’s so special about A.B. 550 is that it would allow the owner(s) of a motor vehicle that is required to take a smog test to pay a 200 dollar smog abatement fee IF the car meets the following criteria:

  • The motor vehicle is 30 model years or older
  • The motor vehicle was manufactured during or after the 1976 model year
  • The motor vehicle fails a smog test
  • The motor vehicle fails a subsequent smog test after necessary repairs were performed

This could mean a lot to hot rodding.  Newer cars are easier and cheaper to insure, parts are more plentiful and cheaper, and, since newer cars have the necessary smog equipment, hot rodders can start to build killer smog-legal street cars.

It’s extremely important to me and many others in the automotive industry that we (as in auto enthusiasts) contact the California Assembly Transportation Committee to voice your opinion of A.B. 550.

Here’s how to do it.  Email Steve McDonald at stevem@sema.org a copy of your letter. Also, send this to your automotive enthusiast friends! The more people who voice their opinions, the more likely the bill is to pass.

Here is a (very) long list of the committee members’ contact information:

Assemblymember Jim Frazier (Chair)
Phone: (916) 319-2011
Email: assemblymember.frazier@assembly.ca.gov

Assemblymember Katcho Achadjian (Vice Chair)
Phone: (916) 319-2035
Email: assemblymember.achadjian@assembly.ca.gov

Assemblymember Catharine B. Baker
Phone: (916) 319-2016
Email: assemblymember.baker@assembly.ca.gov

Assemblymember Richard Bloom
Phone: (916) 319-2050
Email: assemblymember.bloom@assembly.ca.gov

Assemblymember Nora Campos
Phone: (916) 319-2027
Email: assemblymember.campos@assembly.ca.gov

Assemblymember Kansen Chu
Phone: (916) 319-2025
Email: assemblymember.chu@assembly.ca.gov

Assemblymember Tom Daly
Phone: (916) 319-2069
Email: assemblymember.daly@assembly.ca.gov

Assemblymember Bill Dodd
Phone: (916) 319-2004
Email: assemblymember.dodd@assembly.ca.gov

Assemblymember Eduardo Garcia
Phone: (916) 319-2056
Email: assemblymember.eduardo.garcia@assembly.ca.gov

Assemblymember Jimmy Gomez
Phone: (916) 319-2051
Email: assemblymember.gomez@assembly.ca.gov

Assemblymember Young O. Kim
Phone: (916) 319-2065
Email: assemblymember.kim@assembly.ca.gov

Assemblymember Eric Linder
Phone: (916) 319-2060
Email: assemblymember.linder@assembly.ca.gov

Assemblymember Jose Medina
Phone: (916) 319-2061
Email: assemblymember.medina@assembly.ca.gov

Assemblymember Melissa A. Melendez
Phone: (916) 319-2067
Email: assemblymember.melendez@assembly.ca.gov

Assemblymember Adrin Nazarian
Phone: (916) 319-2046
Email: assemblymember.nazarian@assembly.ca.gov

Assemblymember Patrick O’Donnell
Phone: (916) 319-2070
Email: assemblymember.odonnell@assembly.ca.gov

Thanks for listening to my rambling about how this could turn the hot rodding hobby around.  If the bill passes, there will be people who abuse the system, but they already do that.  I wouldn’t worry that much about it.

I think these cars that are only slightly customized could greatly benefit from A.B. 550:

This bone-stock 1976 Camaro could benefit from an LS-motor swap.  Chevy Performance even offers an LS3 E-Rod engine that is smog-legal in all 50 states.  You just install the engine and slap on a couple of stickers that let the smog guys know.  These second-generation Camaros are popular among hot rodders, and one could throw on aftermarket suspension pieces and nobody would notice.

This is a simply tasteful C-10 stepside.  The wheels go well with the dark blue/black paint on the truck.  The big visor over the windshield is a cool touch from the 1950s.  It would be even better if the owner could put a thundering big-block with EFI on it.

This 1985 Fox-Body Mustang is an early Saleen Mustang.  It looks better than the flashier late-model Saleens.  It was a performer in the day, but my Mazda3 could beat it to 60, through the quarter mile, and in just about everything but looks.  If somebody bought a Fox-Body, got a body kit (Saleen rip-off body kits are common in drifting), put in an EcoBoost V-6 found in the Taurus SHO, this would look amazing, and go like stink.  If there was an aftermarket suspension kit on it, even better.  This would be a holy terror at autocross and track day events.  Plus, it would be a fun daily driver.  OK, I’m going to rein myself in now…

The last car on this little list is one I really want.  It’s a Chevy C3 Corvette.  Let me explain. It has stunning good looks, and would be quite the performer with a modern LS engine under the hood.  It’s already been done, and that’s the car in the picture.  It’s got an LS3 E-Rod under the hood, and even though it’s a 1972, one could very easily do the same thing to a 1976 or later model.

The Most Affordable Project Cars!

If you’re a classic muscle car fan, but don’t have anywhere between $35,000 and $100,000 to spend on that perfectly restored Chevy Camaro, don’t worry!

It’s always possible to find a project car for your budget, even if it’s not a Hemi ‘Cuda, Mustang Boss 302, or a Camaro Z/28.  But, who says it has to be one of those to be the coolest person on the block?

These are my choices that have been proven to be total street/strip demons for not a lot of money (you could buy a new Camry for the price of a well-built one).

I’ve always thought that the most important part of the hot rod building process is buying. The better the car, the less work you’ll have to do.

Obviously, there are far more choices than the cars listed below, but if you’re new to hot rodding, start with one of these!  You’ll thank me later.

  • 1979-1993 Ford Mustang:  Yes, there are always a good dozen of them at the local dragstrip, autocross, or drifting event.  But, that’s why people choose them – you can build a killer “Fox” for under $10,000.  Getting a car made after 1987 is what I would go with – they have sharper styling, more powerful engines due to better airflow and more fuel flow.  They are light, dirt cheap, don’t look too terribly bad, easy to work on, and have more aftermarket support than any other car on this list.  You can buy one from $1,500 to $5,500.  If you own one and want a massive supporting community, check out foxbodyforum.com
  • 1965-1970 Chevy Impala:  Yes, a behemoth is here.  In 1965 alone, Chevy sold a whopping 1 million cars.  Only the top-of-the-line Caprice had more options than the Impala.  They look good, but they have performance to back it up:  They had the infamous 409 cubic-inch big-block V-8, as well as the 396 cubic-inch big block V-8 and thundering, coveted 427 cubic-inch L-88 big-block V-8.  In 1970, the 454 cubic-inch big block took over from the L-88.  These big bruisers also came with a host of small block V-8s.  Though they may not be a canyon carver, there is a thriving aftermarket.  Expect to pay $1,500 to $10,000 for a non-L-88 car.  A good website is impalas.net.
  • 1971-1977 Pontiac Ventura:  The less-popular version of the Chevy Nova is a good way to get into hot rodding.  That being said, get a Nova.  While it’s a badge-engineered version of the Nova, it’s less popular and harder to find parts for.  Early Camaro suspension parts are interchangeable, but other than that, not much other Chevy stuff but engines and transmissions are interchangeable.  Paying somewhere between $3,000 and $12,000 is what you should expect.  
  • 1973-1976 Chevrolet Laguna:  This land barge is one of my favorites.  There’s a guy in Sonoma County who’s trying to sell one.  It was famous way back when for it’s wins in NASCAR (it came in right when the HEMI cars went out).  You can do literally anything to a Laguna.  The big engine bay can accommodate a big block, big headers on a small block, or a stroker engine.  The stock fenders can take very wide tires, which make it a good choice for drag racing or road racing.  Expect to pay $1,500 to $6,000 for one.  A good website is g3gm.com.  
  • 1970-1974 Ford Maverick:  When the Mustang’s rampant sales numbers killed the Falcon, Ford introduced the Maverick.  It directly competed with the Chevrolet Vega, but was more fun to drive with an optional 302 cubic-inch small block V-8.  Next to the Chevy small block, the Ford 302 small block is one of the most popular engines in America, making the modifications nearly endless.  Want to make it turn?  Turn to Global West, who makes tubular control arms for the Maverick, making it handle like a true goose (sorry for the Top Gun joke – I couldn’t help it!).  Pay between $1,500 and $3,500 for one.  Go to fordmaverick.com for a community.  
  • 1971-1977 Chevrolet Vega:  Yeah, this was next on the list.  It only seems logical to put Chevy’s offering below the Ford (it doesn’t have a V-8 stock, so it’s below the Maverick).  It was a glimpse into the future with it’s all-aluminum, overhead-cam four cylinder engine.  It also came with an electrical fuel pump and standard front disc brakes.  The suspension, punchy engine, and light weight means that it can be quite the performer with a modern engine.  If I were you, I would get the 3.6-liter V-6 offered in many of GM’s cars today.  It’s plenty powerful, and coupled with a car that weighs 2,300 pounds, will make this car a rocket ship.  Pay between $1,500 and $6,000.  Go to vega-world.com for a community.  
  • 1965-1973 Plymouth Fury:  If you want a stock big block in the 1965-1973 Fury, get a 1970 Fury Sport GT.  It’s got a 440 cubic inch big block topped with six carburetors.  That being said, you can easily drop just about any engine made by Mopar into one of these without a lot of work.  Go to stockmopar.com for a community.  
  • 1967-1973 Mercury Cougar:  Essentially just a Mustang with better styling (in my humble opinion) and a 3-inch longer wheelbase, the Cougar is an excellent cruiser.  It fits in at just about any motorsports scene, and is a crowd favorite at shows.  Pay between $1,000 and $6,000 for one.  Visit mercurycougar.net for a good website.  
  • 1968-1970 AMC AMX:  AMC’s much less popular competitor to the Camaro and Mustang never really caught on, which is a shame.  Yes, it sat two, so it really competed with the Corvette and lighter European sports cars.  They can be somewhat hard to find, due to their low production numbers.  They are more of a collector car, as their owners take pride in them.  Pay between $3,000 and $15,000 for one.  Get a more expensive one – it will be in better condition.  Go to theamcforum.com
  • 1972-1974 Dodge Challenger:  The reason I chose the 1972-1974 version is that the 1970-1971 models are more coveted and expensive.  Swapping a modern 5.7-liter HEMI V-8 under the hood is a popular, economical choice.  If you want to go over the top, shove a Viper V-10 under the hood.  Most buyers choose to restore them rather than radically modify them, so you likely won’t need to spend a lot of money on paint, trim and interior parts.  Pay $2,000 to $15,000 for one.  A good website is cuda-challenger.com
  • 1971-1972 Dodge Demon:  This car was very nearly called the Beaver.  It came as a fastback only, so you could tell it apart from the other drab cars of the era.  While it never would beat a HEMI Charger, it could hold it’s own against a big block Camaro.  The V-8s available are popular with racers today, as they can easily rev to 8,000+ RPM with very little modifications.  They are the Mopar version of the Fox-Body Mustang on this list.  Pay between $1,500 and $5,000 for one.  A good resource is valiant.org
  • 1963-1965 Mercury Marauder:  This car is the Mercury version of the Ford Galaxie.  It’s an entry-level version of the Monterey, and it only came with V-8s – the same engines as the Galaxie.  It came with a fastback roof like the Galaxie, as it helped this big bruiser win in NASCAR.  Pay between $4,000 and $15,000 for one.  A good resource is mercurymarauder.org
  • 1960-1970 Ford Galaxie:  The first-year Galaxie had all of the bling of the 1950s.  It’s a pretty car, but in 1960, it didn’t quite cut.  So, Ford redesigned it.  Halfway through 1963, Ford decided to improve it’s aerodynamics to get the upper hand in NASCAR.  This new slope-back style was called the Sports Roof or Scatback hardtop.  Ford also introduced the mighty 427 cubic-inch V-8 that is legendary in drag racing.  In 1968, Ford replaced the 427 with the 428 Cobra Jet designed for drag racing.  It also got better styling.  In terms of suspension, there isn’t much.  However, you don’t need much to go fast – a 427 Roush crate motor, drag shocks, big drag slicks, and a 9-inch rear end are all it needs for speed.  It’s not meant to be a canyon carver.   Pay between $800 and $9,000 for one.  Go to galaxieforum.com for a community.  
  • 1975-1980 Chevy Monza:  A derivative of the Vega, which was produced two years into the Monza’s production span, the Monza replaced the aging, terrible Vega.  Unlike the Vega, the Monza came with a standard V-8.  This makes it very easy to find speed parts for one.  They even have some race breeding in them, as they competed in the IMSA GT series.  You’ll also see many at the drag strip or in standing mile events, as they are fairly aerodynamic.  Pay $1,000 to $3,000 for one.  Go to v8monza.com for a community.
  • 1967-1976 Plymouth Valiant:  The first generation of the Valiant had a look right out of the 1950s.  1967 gave it a redesign that made it look relevant to the 1960s.  Finding a pre-1973 model is the best, as they don’t have the federally-mandated rubber bumpers.  Plus, they are lighter.  In 1974, it was essentially just a rebadged Dart.  This is good because there are twice the parts available.  One of the most common Valiant models you will see is the Valiant Scamp – it accounted for more than half of Plymouth’s sales that year.  Pay between $1,000 and $8,000 for one.  Again, valiant.org is a good resource.  
  • 1973-1976 Chevrolet Nova:  The Nova is a very popular choice with hot rodders because it is cheap, light, and shares parts with the first-generation Camaro.  Many Novas came with a small block Chevy V-8 stock, but they can easily accept big block Chevy V-8s.  In 1973, the government made every automaker put horrible rubber bumpers on their cars.  However, Chevy put an aluminum cover on the bumpers to minimize the horrible look of rubber.  So, the damage is relatively minimal.  The Nova is one of the most popular cars in the autocross and drag racing circuit, as they are cheap, easy to modify, and are light.  Pay $1,500 to $4,500 for one.  A good resource is chevynova.org
  • 1979-1986 Mercury Capri:  The Mercury version of the Ford Fox-Body Mustang is a love-it or hate-it affair for enthusiasts.  Mercury made multiple versions of the Capri, but they are all cheaper than the Mustang, and share the same parts.  Pay anywhere between $1,500 and $3,000 for one.  A good website is foureyepride.com
  • 1963-1969 Mercury Comet:  The first year of the Comet came with a weak 260 cubic-inch V-8.  In 1964, Mercury saw that people wanted better looks and more power.  The Comet was light, and Mercury made 50 cars that did well in the NHRA Super Stock drag racing class.  The next batch of Comets were true comets, with the powerful Ford small block and big block engines.  The sister cars to the Comet open up an aftermarket for it.  Pay $2,000 to $7,500 for one.  Go to cometcentral.com for a community.  
  • 1982-1987 Oldsmobile Cutlass Supreme:  This is the Oldsmobile version of the legendary Buick Grand National.  GM sold a lot of these cars, so finding one is easy…and affordable.  You can buy one for $500 to $3,500.  They might not be the best choices for canyon carving, but they are a cheap way into bracket class drag racing.  Go to oldsmobileforum.com for a community.  
  • 1964-1974 Plymouth Satellite:  This was the luxury mid-size Plymouth.  It was the only version of the Plymouth Belvedere to come with a V-8.  You could even get the 426 HEMI in it!  They can get pricey, but are fun cars to cruise around in.  Pay about $2,000 to $13,000 for one.  Go to bbodiesonly.com for a community.

This post took a lot of research, and I hope that you enjoy it.  Don’t take the Internet verbatim.  Even what you think is common knowledge should be double-checked.  I recommend getting books on muscle cars.  One of the best out there is the Encyclopedia of American Cars:  A comprehensive history of the automakers and the cars they built, including every major American automobile and scores of minor makes.  It’s a good read, and an even better research.  0912phr 45 O+20 Affordable Project Cars+american Cars Book