Inliners International Forums General Discussion Engines 235 six horse power rating

Good morning,
While looking at the various specs on a 235 chevy six motor, I see that the horse power rating on the 235 stick is 123 HP... The Power Glide is 136 hp.. Both enigenes have the same bore and stroke and run a single barrel Carb.
Where does the addtional horse power come from between the stick and the Automatic.
Thanks
Mike

There were different head castings with smaller and larger combustion chambers and different cams for the 235 over the years.

Also powerglide 235s used hydraulic lifters and a fiber cam gear for a quieter running engine, which however doesn't affect HP.

Powerglides had 1.92 intake valves as well as a different cam.

ahhhhhhhhh.. Thanks Guys... I wonder if they got any better gas milage then the 123 hp engine.. Mine is awful.. about 18pmg...

Thanks again

Dear Mike;

That was really good back then. Gas was less than a 'quarter' per gallon for Regular.

Happy trails.

18!!! My 261 w/3X2's, headers, 260/270 cam and lots of internal work got 26MPG@75MPH in a 41 Chevy pick up, going to Bonneville. What is it in? Something must be amuck.

.25 cents a gallon? Most people where lucky to make .25 an hour in the early fifties. It's cheaper to drive now then back "in the day". My '46 got 23-25 mpg with the ole 216 and 410 gears. That would be about 20 to 22 in U.S. gallons.

It was a little more than that Joe.

I used to get $.50 an hour to do yard work and shortly after that; my first 'gas station' job started at .85 cents plus commision/$50.00 a week.

A "lot of money" back then. :p

When I learned mechanical/electrical work, I got half the labor, which was about $3.50, as I recall.

When I opened my own Service Station in 1968, Regular gas was around .33 cents and labor was $11.00 an hour.

Mike;

The 'early' Powerglide was a very poor design and took about 70% of the engine's power, just to 'get going'. So don't feel bad @ 18 MPG.

Happy trails.

Every year I take a road trip of about 600-800 miles round trip with several guys driving AD type Chevy and GMC trucks.They all have the ability to cruise at 65 MPH,either by screaming the engine or different gears,lol.These are nice trucks with decent tuned reasonably stock engines .The average MPG seems to be about 16,my hotted up 37 Chevy with a GMC 302 gets about 21 mpg in OD.
We have a 50 Chevy pu,stock except for radial tires and a 58 235 engine,runs very nicely.My wife uses it every day ,mostly 45 mph rural driving,the truck gets around 16 mpg.
Most everyone I talk to mentions the lousy fuel mileage of their old GM inline engines,but a few of you get really good mileage.So......tell us the secret!!!!

Armond. it's the compression that makes for milage. A lot of guys who had 8 to 1 283's could not understand why the 10 to 1 327's always got higher milage on the road. I'm sure you don't have 7-1 any more...JD

something must be whack in my truck, I have a 56 chevy truck with a 235 and a stick 3 speed muncie with an overdrive. In O.D. at 65 mph with the stock rearend- like 4.10-ish, with the bigger 261 rochy carb, I get no better than 15 mpg!!!! whats up with that?

Well I don't know what the deal is with these inline 6's.... I had a 250 with a 4 barrel and I got close to 22 with that. This 235 is stock, with a 3 speed stick. solid lifters.. I even changed gears in the year end.. I took out the 3:70 and put in a 3:36/ It runs down the road better, but i still get rotten milage..Now that someone has mentioned compression, That just might be it.. I am sure this thing has more miles on it then the odometer says. I 'll give it a check and see.

There is a nice graph of the relationship between compression ratio and efficiency on the MIT web site -- http://web.mit.edu/16.unified/www/SPRING/propulsion/notes/node25.html
Scroll down to section 3.5.1.

Typical 235s are 7:1 ?
Typical 250s are 8.5:1 ?

Also don't forget that the 235s weigh 150 lbs or so over the 250s.


regards,
Leon

Hey gang,
I pulled the plugs this morning and did a compression check.. first 2 cylinders were 100.
all the rest 115.. they should be 130... I gaped the plugs t0 42 and took it out.. It runs a lot better and comes up to speed a lot quicker. I had a .50 on the plugs.. I think it was just too much gap. Now it runs pretty good. Now milage is another factor, but hey, if we'r e havin fun. who cares..

Thanks

Mike