Lies, Damn Lies and Horsepower

Anyone who has ever set out to plan an engine build has had to deal with the mysteries of horsepower and torque. The internet is full of information - some good, some not so much - trying to explain what these things are and why they are important. Before I start talking about engine mods I'm going to try just this once to nail down the science.

How Fast is Fast?

There is an old saying among hot-rodders and racers: 

"Speed costs money.  How fast can you afford to go?" 

Honestly answering that question is the first step in deciding what sort of car and engine you're setting out to build, else you will likely spiral into a constant game of second guessing yourself - looking for more and more power - that at best will cause  you to spend more than you have to and at worst will prevent you from ever actually finishing your car!

It takes at most 50 horsepower for a typical mid-size car to cruise at 100 mph.  The BMW Z3 coupe - with similar size and aerodynamics as our beloved S30, and with 228 crank horsepower (in the ballpark of a stout L28 street build) - has a top speed of 155mph. Any modern car can easily reach the century mark - even though in most of the US you can't drive faster than about 85 mph without losing your license. On the street, top speed is not nearly as important as acceleration: how quickly can you speed up to change lanes or merge into highway traffic or pass a lumbering truck on a two lane road.

Do you really want a silk purse?

When I was a snot-nosed kid growing up in small town Pennsylvania, having your own car was the Holy Grail of high school life. Unless your parents were especially well-off and especially generous, having a car at age 17 meant saving up several years of less than minimum wage income, buying a worn-out car and then learning to wrench it back to life. One of the things we learned kind of quickly was that the actual wrenches came in 3 varieties:

• No-name stuff they sold at the no-name discount store that were really cheap and quickly broke.
• The shiny Proto tools hanging on a big display behind the counter at the NAPA store; the chrome would have looked at home on a '57 Chevy. These were really pretty and never broke, but you could spend a whole week's paper-route money on a single socket!
• And then there were Craftsman brand tools from the Sears store. Less than half the price of the Proto stuff, not quite as shiny but with the same lifetime guarantee (this was back in 1976 - sadly things have changed -  the quality of Craftsman tools has slipped and Sears itself is on shaky ground). Like a lot of my friends, the Christmas after I turned 16 I got the 100-piece Craftsman tool set under the tree - 1/4, 3/8 and 1/2 inch drive ratchets and sockets and a set of combination wrenches in a nice steel toolbox.  I think back in 1976 that set cost all of $99. And I still have most of those wrenches today!

What does this little trip down memory lane have to do with old Datsuns? Simple enough, whatever part you want to buy or repair you want to make, there will usually be 3 options: something cheap that will quickly wear out or break, something fancy and really expensive, and something that is not cheap or fancy but will work well and last forever.

A lot of the folks you'll find working on old cars have technical backgrounds: there are the unsurprising machinists and mechanics and engineers, but also computer programmers and finance guys and various kinds of health care workers. They tend to be the people who have to be fanatical about doing thieir job just right. Doing a half-way job on a car that you are passionate about is unthinkable, but doing everything to perfection uaully means never getting to the point of having a car that you can drive and have fun showing off and taking places. When you're planning out a restoration or engine build it is tempting to go for all the fancy stuff. For any one part its often just a few dollars more, and when you're going back and forth between which thing to buy you start thinking "I'm only going to buy it once, I might as well go for the best". The hidden gotcha is that by adding 20% (or more) to the cost of everything, you're likely stretching out the day when you have the money to actually finish the car - if you don't lose interest before that happens!

Its not just money, sometimes its actually time. This occured to me in the middle of a project to spiff up the interior of my 260Z. I had bought new seat covers and foam seat inserts from Banzai Motorworks and the fellow who runs the place recommended ACC Carpets. They had reasonable prices, so I bought a set - no hassles, came quickly. Then I pulled the old carpets out, and while the floors were still pretty solid there was some ugly rust where the floor pans were welded together and a spot under the passenger seat where I suspect someone spilled something corrosive (maybe a Coke?) many years ago. No problem, I think - I'll just use one of the rust converters to clean them up and put a coat of "rust encapsulating" paint on them before I put the carpets in.

After a couple weekends this job just got bigger and bigger.  The jute padding on the transmission tunnel smelled like a wet dog - I pulled it up and used Goof-Off glue remover to cleanup the paint underneath.  The sound deadening "tar mats" were removed - through a combination of dry ice (about $50 worth), heatgun (had  to buy that too) and a putty knife (I  thankfully already had). I read up on rust-converters and bought a gallon jug of Evaporust and followed the directions: spread paper towels over the rusty floors, soak it with the Evaporust liquid and cover with plastic garbage bags to keep it from drying out. The rust came up, but slowly. Sanded some of the worst pitted areas and applied a heavier dose of Evaporust. Started to see bare metal. Switched to MetalBlast, a  phosphoric acid based product that removes and neutralizes rust and etches the steel in preparation for paint (it also removed a lot of the remaining factory paint). And finally I brushed on two coats of RustBullet.

Before

Evaporust followed by Metal Blast

A lot of rust removed

After two months of weekends the floors look better - 45 years of crud have been removed, 95% of the rust is gone and there is paint covering bare metal - but to be very honest it doesn't look like the professionally sand blasted and epoxy sprayed interiors you see on the $50,000 restorations on the intenet. And oh-crap, I've been crawling in and out of the car so much that the ancient weatherstripping on the door frames - which weren't all that bad to start with - have started to disintegrate.

Two coats of Rust Bullet

This is where you have to apply the "silk purse" thinking. How important is removing all of the surface rust from the floor - that is just going to be covered up with a carpet? On a car that never goes out in bad weather? When I'm an old guy who will be lucky to still be driving  a car with no power steering 10 years down the road? Did I really have to do all this? Well, maybe... but only for the warm fuzzy feeling it gives and not for any practical reason.

When I bought my Z, I searched hard to find a fairly complete car with a solid body and minimal wear and tear. I set an informal search radius of 200 miles, and spent a lot of weekends driving to look at Datsuns. Along the way I passed on a few nice looking and nice driving cars that were either patched-up (wheel openings made largely of Bondo) or where the seller was obviously misrepresenting the condition of the car (e.g. claiming original paint on an obvious re-spray).  Eventually I found a 260Z with not too much rust in the usual places, with a nice looking but not too-recent re-spray and an interior you weren't afraid to get into without a recent tetanus shot. Sure, the engine ran a bit rough, the AC didn't work and the suspension had a metal-on-metal feel, but all the pieces were there. The repairs it needed were things that bolted on.

If you read the collector car buyer guides, I did all the right things, but looking back I did something very wrong: I bought a car that you could drive but that no one really wanted to drive. Getting the car to that driver level - not just moving under its own power with the road manners of a worn out pickup truck, but feeling like an honest-to-God sports car - was a lot of work and money, where all of those there-but-nearly-worn-out parts need to be replaced anyhow. And if you don't have the money, time and facilities to get to that driver level, you are likely to end up with a neglected project car moldering in your garage.

It's too late for me, but if you're just starting down the collector car path, do yourself a favor: either buy a car that truly drives well, or if you can't get the perfection-monkey off your back start with a basket case car where you know you will have to completely replace everything. Trying to walk the middle of the road is a good way to get run over!

One day at a time

In the software engineering world there is a famous book - The Mythical Man Month by Fred Brooks - that tells of the trials and tribulations of one of the first big software projects (the development of the IBM 360 operating system).  The book has a joke that has become famous in the software biz:

Q:  "How does a  project get to be a year late?"
A:  "One day at a time!"

If you're the least bit interested in engineering you should track down a copy of the book and give it a read, but the point of this joke is that there are an endless list of minor set-backs that delay every project - a key employee has the flu, a part is delayed in shipping, a manager asks for a demonstration, the system fails in some unexpected way and requires rework - and all those tiny, impossible to predict delays simply add up.

Thats how my Datsun 260Z managed to sit unmoving in my garage for most of the last 15 years, often trapped by boxes of household junk. Every now and then I'd get it started and drive it to work or to a car show or something, but it was always a bit of an ordeal. The car didn't run well or drive well and it rattled and smelled bad inside.