Hot Rods Horsepower minimum, got a number?

Describes my first ride at 12 years old in my pals' older brothers Sunbeam Tiger.

 

It's difficult to compare apples to oranges .... & Then quantify it into any thing more than a feeling , unfortunately , that's what ex-spurts attempt to do .

 

You need enough to "WAX" a 911 Porsche at the stop light, my 425 nailhead in my 29 Ford roadster gets it done. I'm thinking 400hp is good.

 

I can’t afford to win any wallet races so I get my kicks doing the most with the least. I’m happy with my bangers.

 

Build an "Atkinson cycle" engine from the stock 144" [or 170"]

You deck the block so the flat top pistons are above the compressed gasket height, then flycut the combustion chambers for piston clearance
You want about 13.0:1 static compression [plus]

You hunt down a good cam grinder to do a custom grind ,where the closing of the inlet valve is delayed further up on the compression stroke for a dynamic compression ratio of 9.0:1. to 9.5:1
The net result is that the engine has a greater effective expansion than compression

You would want a decent ignition, single barrel carb, and 5 speed manual trans, low rolling resistance tyres

A lightweight vehicle like an early Falcon / Ranchero should easily net 35-40 mpg.[average mpg in real world driving]

If you wanted to go "off topic", vulture a Toyota 1NZ-FXP engine which is already an Atkinson cycle engine [1500cc and 76hp]
These engines are "sale proof" because they are so reliable, that there is no 2nd hand market for them

 

Hello,

As a teenager, I felt plenty of horsepower in our vehicles. And one that was the most fun, but lacked horsepower for any steep slope on our coast highway travels. The Flathead powered 1940 Ford Sedan Delivery ran like a top, never faltered for any repairs and gave us endless smiles on our thousands of miles of coastal searching and enjoyment.

But, it was severely lacking power. If you have to downshift to 2nd gear or even first to make it to the top of a steep coastal road or are prevented from going up to the local mountain cabins and ski resorts due to lack of power, then alternatives are/were necessary.

At one time our 1958 Impala was all that we needed for winning at the dragstrip and on any street of our cruising. It was advertised as 280 hp, but it was more like 350 with a cam/lifters, polished ports/head, and a definite 14 second quarter mile car when needed. The C&O Stick Hydro + 4:56 gears made believers out of a lot of 55-56 modified 283 Chevy sedans with 4 speeds+. No one got away from the stop light as fast as our Impala with the C&O Stick Hydro.

It came down to tuning, and concentration for quick reaction times when it was necessary to go. The C&O Stick Hydro was excellent for super quick starts from the line. If I could keep the power going, it was lights out for the guy in the next lane. 6 red Impala tail lights told the story. The last thing we were able to do after our A/Stock class racing was over was to modify it with a cam/lifters and port polish for a little more h.p. My brother had it dyno tested and for the early versions of the dyno and our tuning, it registered 280-290 hp at the rear wheels.

At the time, there were other 348 motor models and the 315 hp was the top of the line. But, hard to get at the time of ordering in the fall of 1957. As the 409 motors came out, it was over before it got started. No way a 280 hp Impala was going to blast by a 360 hp 409 Biscayne of our teenage friend. So, it was intimidating enough to look at and since it did not race anyone except for some fun challenges against the 58 Impala. that was all that it took to have fun and still be friends.

The C&O 58 Impala got out so far in front at the start that the owner of the 409 Biscayne saw the 6 red taillights signaling the “race” was over. No quarter mile race, and close to an 1/8th mile, but a little sooner. I could see the 409 coming up fast, but, by then, the RED lights signaled it was over. Ha! Almost 100 hp advantage was not something to challenge. Then and now. All smiles and great fun for all concerned.

Jnaki

These days, my wife enjoys a full throttle acceleration going up the steep roads near our house, now and then. When I stomp on the pedal, her listed 300 hp little station wagon heads up the hill and everything seems to flash by quickly. The same exact model has been clocked a 13 seconds in the quarter mile by a drag race driver in his own version.

So, it is not just pure horsepower, but in a smaller lightweight family road trip car, anything can happen. She does not hear the pure power sound, but when it comes on, it is fun. Even for a couple of old folks enjoying our road trip coastal drives on empty roads.

The great thing is, it always starts up, runs great and is so comfortable that our pre pandemic road trips up to the San Juan Islands was a snap… comfortable, safe, power when we needed it, and extremely, FUN! But, she keeps telling me if we ever have to go live in the mountains of inland California or somewhere in Colorado, she would get a 600-700 hp all wheel, drive crew cab truck for our desolate road trip needs. She likes to have the power when she needs it… yikes! YRMV

 

This seems to have become relevant: https://www.jalopyjournal.com/forum/threads/ultralight-cars-how-low-can-you-go.246587/

 

This was hot rod building 101 back in the day

 

You need enough power to pass safely on the Hwy. My sis was almost killed on a 2 lane Hwy when she decided to pass a car with our 82 Ford Escort Wagon (auto). It had been gifted to us by our uncle. Had a measly 70 hp. Couldn’t believe Ford could build such a car.

 

My old '56 F100 had a 305 SBC and TH400 and 2.73 gears that probably put down 140-150hp to the tire, and it was still a blast around town and on the highway. My current '56 F100 has the motor out of one of my old OT street cars and put down 670hp to the tire in it's previous form with a powerglide. Now, with the OD trans, 3.73 gear and a much lighter truck, it's going to be a riot.

HP is one thing, but gearing is everything. Even my newish F150 DD makes 325hp out of a little V6, backed by a 6spd Auto and 3.55's, the truck absolutely rips.

 

if it's a daily driver I would prefer some light oomph but not at the expense of a 100$/wk gasoline bill. So doing some quick math, about 230hp max.
But again it's different if it's 16lb/hp or 11lb/hp. or the rearend has highway gears.
My truck here, I can time eggs boiling but I love driving it.