All Small Six Power ratings.

[aussie7mains]

OK, since things are a bit quiet here I thought Id open up a new topic. So with that in mind Id like to give some opinions, which I base on some experience and some rational thought, now in all cases I will be talking about NET or DIN power ratings which is as close as you get to actual installed power, NOT the sometimes OTT ratings given in many magazine articals. So the 200 crossflows were rated at 118bhp and the same year 250EFI was 155, those are pretty honest, the older pre crossflow were around 120 for the 250 (taken from brochures for industrial engines) the 200 probably about 85-90bhp. A 302 windsor 2 barrel around 155 a 4v around 170. A 351 4v cleveland (Australian 4v with 2v heads) 220bhp, this would have been equivilent to a 1970s 300bhp engine. I would estimate the 250-2v in factory trim to be around 130-135, a 200 with a 2v head around 100. These are all way less than the factory ratings, but we all know they were "sales based". So discuss!

 

[rocklord]

In the US, horsepower rating was changed from "Gross" to "Net" after 1973.
My rule of thumb for converting is to divide Gross HP by 1.4 to get Net HP.
So my 65 Mustang's 200cid originally rated at 120HP Gross is 85HP Net.

 

[bubba22349]

Yes often times people get very upset after having their cars Dyno'ed and get a rear wheel HP reading. Plus then comparing that to the older cars "sales based" HP numbers used here in USA until around 1971 or 72 or else they will compare those early engine Ratings to the 1973 up engines thinking those newer engine can't be as good but it is just not a direct comparison using these old posted sales ratings to the more accurate Chassis Ratings. Those First HP rating were a Fly Wheel HP and the engines were run with No Fan, Generator / Alternator, Water Pump, Power Steering, Air Conditioning Compressors, or any Emissions Equipment, Belts or Pulleys, no Clutch or Transmission, Driveshaft Etc. plus with an Open Exhaust System all of which makes a Big difference in the HP Readings. My first experience in seeing this HP discrepancy was as a Teen in the 1960's and I was at Sachs & Sons Lincoln Mercury's Shop in Downey, California, one day. They had just did a good Tune Up and then a Dyno Pull on a 1963 to 1965 Pontiac Tempest 326 V8 to see what it would do. They were fairly decent running engines, LOL still it put down a whopping 85 HP to the rear wheels.

 

[Kritas]

I wish I had a dime for every time someone has given me a horsepower estimate that they've calculated. Dyno, or it didn't happen.

 

[THE FRENCHTOWN FLYER]

I wish I had a dime for every time someone has given me a horsepower estimate that they've calculated. Dyno, or it didn't happen.

Likewise, if I had added up all the horsepower improvements I've been promised over the years just for using such-and-such part or machining process I'd be running in the 2's!

 

[drag-200stang]

0 to 60 or better yet 1/4-mile time and wieght of car, everything else can be cheated. Remember the 340 hp one barrel NA 200 dyno. That is why a lot of people never take their car to the drag strip, so people will not see it is mostly show and no go.
I am a what ever dude , show me.

 

[John Ha]

0 to 60 or better yet 1/4-mile time and wieght of car, everything else can be cheated. Remember the 340 hp one barrel NA 200 dyno. That is why a lot of people never take their car to the drag strip, so people will not see it is mostly show and no go.
I am a what ever dude , show me.

I guess I'm mostly a "whatever" guy. I always liked the old Rolls Royce "Adequate" horsepower ratings.

 

[Kritas]

I have a 200 block and a 250 head. From my compression tests, I'm guessing the CR is about stock, say 8.2:1. I'm adding headers and a 2.5" exhaust with a Weber 38 carb. I'm using synthetic oil (some folks say you can make minor HP with it.) I put in an HEI distributor, but I don't think that will do anything for HP. I did repaint the engine, which has to be worth something.

So, what's everyone's guess on the HP? Stock was 85 HP net, no?

 

[aussie7mains]

As another example, when i was a first year apprentice I had a 69, 221ci falcon ute, I did a "tune up" at the tech school I went to, then it was put on the vane chassis dyno the tech had, 75hp!!! It was rated at 135, so where did the 60 hp go? It was never there! Much later i was involved with natural gas conversions of diesel engines, we had 3 engine dynos on site, all eddy current units, we calibrated the torque transducers about every 6 months with an arm and certified weights. We ran engines at full torque and full power for up to 8hours, I can tell you this is hard work for these engines, the biggest we did was a 12litre Deutz V6, it made around 300kw and nearly 1500nm torque and it could do it all day. the heat generated by the brake was huge, we had 100mm copper pipes and a big pump to transfer the cooling water to a 600kw cooling tower. The engines radiant heat could raise the temperature of the air in a huge room by about 10c after a few hours. All these modern Superflow dyno test are for toy engines, most only take a few seconds, and I believe this is because the operators know their test subjects will fail if the engine is held full throttle for very long. The only exceptions seem to be the road racer guys, especially nascar and f1, and it takes a huge expensive effort to get that level of power and durability.
Crikey ive just edited the word BIG, i had put "bike" fat fingers!

 

[aussie7mains]

I have a 200 block and a 250 head. From my compression tests, I'm guessing the CR is about stock, say 8.2:1. I'm adding headers and a 2.5" exhaust with a Weber 38 carb. I'm using synthetic oil (some folks say you can make minor HP with it.) I put in an HEI distributor, but I don't think that will do anything for HP. I did repaint the engine, which has to be worth something.

So, what's everyone's guess on the HP? Stock was 85 HP net, no?

85bhp-90. Down here Ive heard that the Holden 202 in stock trim, a good one get 90bhp. There is a class of racers that run these engines with very limited mods allowed, they recon just of 130 for a really well developed unit. Im still puzzled why you guys bother with the 200ci six?

 

[Kritas]

85bhp-90. Down here Ive heard that the Holden 202 in stock trim, a good one get 90bhp. There is a class of racers that run these engines with very limited mods allowed, they recon just of 130 for a really well developed unit. Im still puzzled why you guys bother with the 200ci six?

It came with my car.

 

[Frank]

As another example, when i was a first year apprentice I had a 69, 221ci falcon ute, I did a "tune up" at the tech school I went to, then it was put on the vane chassis dyno the tech had, 75hp!!! It was rated at 135, so where did the 60 hp go? It was never there! Much later i was involved with natural gas conversions of diesel engines, we had 3 engine dynos on site, all eddy current units, we calibrated the torque transducers about every 6 months with an arm and certified weights. We ran engines at full torque and full power for up to 8hours, I can tell you this is hard work for these engines, the biggest we did was a 12litre Deutz V6, it made around 300kw and nearly 1500nm torque and it could do it all day. the heat generated by the brake was huge, we had 100mm copper pipes and a big pump to transfer the cooling water to a 600kw cooling tower. The engines radiant heat could raise the temperature of the air in a huge room by about 10c after a few hours. All these modern Superflow dyno test are for toy engines, most only take a few seconds, and I believe this is because the operators know their test subjects will fail if the engine is held full throttle for very long. The only exceptions seem to be the road racer guys, especially nascar and f1, and it takes a huge expensive effort to get that level of power and durability.
Crikey ive just edited the word BIG, i had put "bike" fat fingers!

Yes sir, the "real" diesels have it going on. I'm convinced that their incredible longevity while producing torque @ 2.2 lbs/cube is a combination of their no-cut-corners build and the modest speeds they are governed to. Engine life is shortened if too much is asked of it, in induction OR high rpm.
You're right, any engine can produce big #'s for 6 seconds in the sterile cool environment of the dyno cell. As much as I like Engine Masters, most of the info (not all) is useless in my public-street driving world.

 

[bubba22349]

I have a 200 block and a 250 head. From my compression tests, I'm guessing the CR is about stock, say 8.2:1. I'm adding headers and a 2.5" exhaust with a Weber 38 carb. I'm using synthetic oil (some folks say you can make minor HP with it.) I put in an HEI distributor, but I don't think that will do anything for HP. I did repaint the engine, which has to be worth something.

So, what's everyone's guess on the HP? Stock was 85 HP net, no?

Tighten up the 200's "Quench Distance" so its .030 to .040 and then Mill the Head to 52 CC's to raise that Compression Ratio to 9.2 to 1 and it will still run on the cheap 87 Fuel plus with all your other Mods you should come in around 110 HP or so.

 

[Kritas]

Tighten up the 200's "Quench Distance" so its .030 to .040 and then Mill the Head to 52 CC's to raise that Compression Ratio to 9.2 to 1 and it will still run on the cheap 87 Fuel plus with all your other Mods you should come in around 110 HP or so.

I'm buying John Ha's chrome trans dipstick. In the ad, he promised that it would increase horsepower. We'll have to factor that in.

 

[bubba22349]

85bhp-90. Down here Ive heard that the Holden 202 in stock trim, a good one get 90bhp. There is a class of racers that run these engines with very limited mods allowed, they recon just of 130 for a really well developed unit. Im still puzzled why you guys bother with the 200ci six?

What's not to like the little 200 Six's are the most plentiful here in the USA plus they are the Lightest Weight and Smallest Six ever made with lots of potential in a light weight Car. Besides aussie7mains, we didn't get to have all those great choices in the many Six's that Australia and New Zeeland had in the CrossFlow's and the Barra's. I do like all our 250's, 240"s & 300 Sixes as well as the all other early Antique Ford Six's from the Flatheads on up.

 

[bubba22349]

Likewise, if I had added up all the horsepower improvements I've been promised over the years just for using such-and-such part or machining process I'd be running in the 2's!

0 to 60 or better yet 1/4-mile time and wieght of car, everything else can be cheated. Remember the 340 hp one barrel NA 200 dyno. That is why a lot of people never take their car to the drag strip, so people will not see it is mostly show and no go.
I am a what ever dude , show me.

Yes the Drag Strip is the Optimate Dyno!

 

[aussie7mains]

Yes sir, the "real" diesels have it going on. I'm convinced that their incredible longevity while producing torque @ 2.2 lbs/cube is a combination of their no-cut-corners build and the modest speeds they are governed to. Engine life is shortened if too much is asked of it, in induction OR high rpm.
You're right, any engine can produce big #'s for 6 seconds in the sterile cool environment of the dyno cell. As much as I like Engine Masters, most of the info (not all) is useless in my public-street driving world.

The one I watch occasionaly is "power nation" its on Bloomberg TV which I get free with my package, most of the bloomberg stuff is rubbish, and power nation is for the people who know very little about automotive engineering. Everyone ONLY tests for maximums, they never touch anything part throttle, and Ive have rarely seen anything under about 3000rpm. I did have a thought that the superflow brakes did not have the ability to absorb much torque under that rpm, they are tiny brakes compared to the eddy current ones we were using. Low temps really helps. In any event they are not very real world stuff.

 

[bubba22349]

In the area I grew up there was one of the Clayton Dyno Factory's (El Monte Calif.)

 

[aussie7mains]

In the area I grew up there was one of the Clayton Dyno Factory's (El Monte Calif.)

There is an Australian company making dynos "dyno dynamics" in Melbourne, we had two of thiers, both adapted telma retarders for the brakes, they do there own software. Later we got a two PRC copies of Schenk setups, they were pretty good. I used to do the fit ups and test apparatus for them, drive plates etc etc. We also did our own ECUs and fuel injectors. it was a shoestring budget, but worked pretty well. Tata uses it. Ive chucked up some piccies from westport in Perth many years ago, One is my work area with machines, the others are dyno test areas and engines being set up for EFI natural gas.

 

[bubba22349]

Wow that's a very nicely equipped Shop!