Horsepower

[Kurt in NJ]

Those are more or less the numbers I achieved on Pendine Sands in the 29 CCPU in my avatar - B engine with an ali Winfield head, SU1R cam, single 97 and Mallory distributor (actually 69.87mph @ 2411rpm) with a 3.27 rear end on 21"s. It will go faster on tarmac, but not by much.

Really doubt it's making 80hp though.

There's a formula somewhere for calculating power from measured speed/gearing/frontal area. I'll go look it out if somebody will tell me the frontal area of a 29 CCPU

I would think with all that it would go faster----I could get 67 indicated on speedo out of my nearly stock A ---I got stopped once for doing 65 in a 50, thought I was only going 62 so perhaps it could go 70 when showing 67 ("do you know how fast you were going?--a bit over 60---what's under the hood, is it a hot rod?---no it's stock--I don't believe you, show me---I open the hood and he sees the zenith updraft ---then he said--I'm not even going to write you a warning, just keep the speed down)

My engine is baisically stock, it has a "B" cam in the engine and "B" dist cam, stock 3:78ratio, stock head(4.2 comp ratio)----I did put in valve seats so I could have the seating area high and narrow ---I doubt that my engine makes much over 40-45HP, and have averaged 23mpg at 65mph--not just ashort jaunt at 65, was over 1000 miles at 65

I have been trying to "shorten it's life" for the last 25 years by doing everything said to be bad for babbitt---lugging, full advance lugging, and going fast for long drives, it has proven to me that there isn't much you can do to save bad babbitt, and there isn't much you can do to hurt good babbitt(not including running out of oil, or coolant)

 

[Terry NJ]

My basically stock coupe ( I can't tell you what the bore and stroke and valve Dia, or the cam grind is) but it runs strong. I think there may be a HC head. I think there may be a few lbs off the FW. A "B" carb. and ported and polished stock manifolds But when I get to 65 mph it makes noises and vibrates like it's saying "No, I don't want to go that fast!" I don't know what I'm doing wrong.
Terry

I would think with all that it would go faster----I could get 67 indicated on speedo out of my nearly stock A ---I got stopped once for doing 65 in a 50, thought I was only going 62 so perhaps it could go 70 when showing 67 ("do you know how fast you were going?--a bit over 60---what's under the hood, is it a hot rod?---no it's stock--I don't believe you, show me---I open the hood and he sees the zenith updraft ---then he said--I'm not even going to write you a warning, just keep the speed down)

My engine is baisically stock, it has a "B" cam in the engine and "B" dist cam, stock 3:78ratio, stock head(4.2 comp ratio)----I did put in valve seats so I could have the seating area high and narrow ---I doubt that my engine makes much over 40-45HP, and have averaged 23mpg at 65mph--not just ashort jaunt at 65, was over 1000 miles at 65

I have been trying to "shorten it's life" for the last 25 years by doing everything said to be bad for babbitt---lugging, full advance lugging, and going fast for long drives, it has proven to me that there isn't much you can do to save bad babbitt, and there isn't much you can do to hurt good babbitt(not including running out of oil, or coolant)

 

[tinkirk]

My basically stock coupe ( I can't tell you what the bore and stroke and valve Dia, or the cam grind is) but it runs strong. I think there may be a HC head. I think there may be a few lbs off the FW. A "B" carb. and ported and polished stock manifolds But when I get to 65 mph it makes noises and vibrates like it's saying "No, I don't want to go that fast!" I don't know what I'm doing wrong.

Terry

I have a 30 roadster that I'm lucky to get 58 out of
Not sure why bored 60 over other than that it is bone stock
So the 29 I'm looking for more power
Terry


Sent from my iPhone using Tapatalk

 

[Juggler]

I would think with all that it would go faster----I could get 67 indicated on speedo out of my nearly stock A ---I got stopped once for doing 65 in a 50, thought I was only going 62 so perhaps it could go 70 when showing 67 ("do you know how fast you were going?--a bit over 60---what's under the hood, is it a hot rod?---no it's stock--I don't believe you, show me---I open the hood and he sees the zenith updraft ---then he said--I'm not even going to write you a warning, just keep the speed down)

My engine is baisically stock, it has a "B" cam in the engine and "B" dist cam, stock 3:78ratio, stock head(4.2 comp ratio)----I did put in valve seats so I could have the seating area high and narrow ---I doubt that my engine makes much over 40-45HP, and have averaged 23mpg at 65mph--not just ashort jaunt at 65, was over 1000 miles at 65

I have been trying to "shorten it's life" for the last 25 years by doing everything said to be bad for babbitt---lugging, full advance lugging, and going fast for long drives, it has proven to me that there isn't much you can do to save bad babbitt, and there isn't much you can do to hurt good babbitt(not including running out of oil, or coolant)

Pendine Sands is a beach. Running on sand is not conducive to high speeds, and the course is fixed at a half mile with a further 100 yards through the traps.

Not the full 7 mile course available in the 1920's when it was the fastest place on earth

 

[Terry NJ]

Chances are it was bored, not for HP, but because the Cylinders were worn out and the previous owner(s) had it done. I say that because if they wanted moreHP, they would have hung more goodies on it. I have a stock head that I'm going to measure the thickness of for comparisons . Most times when a engine has some machine work done on it, one thing they almost always do is cut the head for flatness. Some rebuilders will "deck" the block as well. This all adds to the compression. Also, boring an engine will result in higher compression ratio too, without cutting the head.
Terry

I have a 30 roadster that I'm lucky to get 58 out of
Not sure why bored 60 over other than that it is bone stock
So the 29 I'm looking for more power
Terry


Sent from my iPhone using Tapatalk

 

[Tom Wesenberg]

I would think buying a used turbo from a junkyard would give the largest horsepower gain for the least amount of money spent.

I'd be happy with a 3.27 ring and pinion, high compression head, and counterweighted crankshaft.

No matter how much horsepower I had, I'd never want to drive faster than 60 MPH.

Modern cars run so smooth, quiet, and have so much horsepower, that it encourages people to drive faster than they should. Plus they have become more self centered and rude, and they tailgate and drive distracted, so I'd rather switch to less traveled roads than try to keep up with the speed nuts.

 

[updraught]

What's a "flowed Model-B carb"?

 

[Terry NJ]

I don't know if you're asking me, But mine is not "flowed" It's just a "Terry" rebuild. Some carbs. are referred to as "Flow Tested" but that involves testing with special equipment. Something I don't have.
Terry

What's a "flowed Model-B carb"?

 

[BRENT in 10-uh-C]

.

Absolutely correct, You have to make your own decision and research it all.

I was told by a couple "in the know" Model A folks that my motor would not run because it has no flywheel.

In racing, the trick is to ask questions.
To go fast, you have to ask the right questions and people.

J

I'm a racer, and I can unequivocally tell you that asking questions from fellow racers will put you at the back of the field!!

 

[George Miller]

Yup no true racer is going to give his tricks out. He may give you one that every one else knows.

 

[V4F]

counter weighted crank , balanced , insert rod/mains . full flow oil system , v8 modified oil pump , b cam . hc head , weber carb ........... that should put you there +

 

[tinkirk]

Terry,Brent,V4F,
I read alot in between the lines and, pick and chose what route to take
So, So far this is where I'm at
Bored 125 over, AER pistons,Rods, insert bearings
Counter weighted the crank, Lighting the flywheel not sure how much off as of yet still working on that
Stipe 340 cam
Snyder 6.0 head removing .010 Best head gasket, piston sticks out the top .051 head right now has a .052 recess cut in it removing .010 off that ,head gasket crush should be .053-.055 so this should leave me with about .042 of quich area
Valves are in. 1.750, ex. 1.50
As of right now the plan is yet this year to still run the A intake and carb
This will be the hangup and only time will tell
Looking at Tod's intake from Snyder's and maybe the Weber carb that they advertise
Thanks all and any Info you may have is greatly appreciated
Tinkirk/Terry
PS i'm sure I have forgotten something

 

[Terry NJ]

Pay attention to "Valve Float"! These old engines weren't built with high revs and valve float in mind. Stronger springs and adjustable tappets seem an improvement that one would have to consider when making the engine go faster.
Terry

Terry,Brent,V4F,
I read alot in between the lines and, pick and chose what route to take
So, So far this is where I'm at
Bored 125 over, AER pistons,Rods, insert bearings
Counter weighted the crank, Lighting the flywheel not sure how much off as of yet still working on that
Stipe 340 cam
Snyder 6.0 head removing .010 Best head gasket, piston sticks out the top .051 head right now has a .052 recess cut in it removing .010 off that ,head gasket crush should be .053-.055 so this should leave me with about .042 of quich area
Valves are in. 1.750, ex. 1.50
As of right now the plan is yet this year to still run the A intake and carb
This will be the hangup and only time will tell
Looking at Tod's intake from Snyder's and maybe the Weber carb that they advertise
Thanks all and any Info you may have is greatly appreciated
Tinkirk/Terry
PS i'm sure I have forgotten something

 

[tinkirk]

Oh yea have them also

 

[Terry NJ]

Terry,Brent,V4F,
It sounds like you have or are going to have the core of a pretty powerful Mod A engine. You've got all the components of a great engine minus the gas to fire it. I have believed that the carburation on the Mod A is poor at best, with 200 C.I., stock cam, etc, etc, etc! Add your mods and it only gets worse. Take your manifold and at least polish it out then add a rebuilt "B" carb., it's a bolt on! The only thing you will need is $10 fuel line for the fittings. The "B" carb has larger throat to process more gas/air mix for the same C.I. Just sayin'!
Terry

Bored 125 over, AER pistons,Rods, insert bearings
Counter weighted the crank, Lighting the flywheel not sure how much off as of yet still working on that
Stipe 340 cam
Snyder 6.0 head removing .010 Best head gasket, piston sticks out the top .051 head right now has a .052 recess cut in it removing .010 off that ,head gasket crush should be .053-.055 so this should leave me with about .042 of quich area
Valves are in. 1.750, ex. 1.50
As of right now the plan is yet this year to still run the A intake and carb

 

[PC/SR]

With those mods, you have wasted a lot of money if you stay with the stock A manifold and carb.

 

[BRENT in 10-uh-C]

Take your manifold and at least polish it out then add a rebuilt "B" carb., it's a bolt on!

With those mods, you have wasted a lot of money if you stay with the stock A manifold and carb.

Terry, you are somewhat correct but if the other Terry follows your advice, he probably would lose some Hp. Manifolds & port runners do not like polishing. Instead, bore the Model-A draw tube to 1.300" (-stock Model-A size is 1.000" and Model-B is 1.250") and then stipple it. If this seems odd, look at a golf ball and then research the ball's surface. There are other tricks (--or secrets) that coincide with this, and a Model-A performance engine builder will know these.

With regard to carburetor, yes a 1.250" throat-sized B carb is easier to use however a Model-A carburetor (not a Tillotson or aftermarket) can be reworked internally to flow enough fuel. The only place I have noticed where the extra air from the B carb has been an advantage is at actual WOT. Even for a Model-A cruising at 55-60 with an overdrive or hi-speed ring & pinion, you are not at WOT. Also, the biggest benefit I see with an aftermarket exhaust is the scavenging effect you receive with running a collector on long primary tubes. The caveat is it takes velocity to create the vacuum or scavenging effect, -which unless you are racing never really enters in. In addition to that, a Model-A has too large of an exhaust valve & port. Then, you lose the full effect of the scavenging by using the stock Model-A exhaust & muffler, so my view is unless you building an engine for competition, go with the combination I mentioned way back in post #9, ...and if you are seeking a faster cruising speed, spend the money you were going to use on purchasing the exhaust header & Weber carb and buy a 3.27 ring and pinion.

 

[Terry NJ]

Brent, You are absolutely correct! The main runner must be bored out to at least 1.250 for it to work (model B carburetor) and I forgot to mention it. I know of the "discussion" in the hobby/industry regarding polishing ports. Some are in favor of it and some are on the other side and feel that too smooth a surface will not break up the tiny droplets of gas as well as a rougher surface. Myself, being a pilot, have first hand experience with air passing over smooth versus rough surfaces and smooth wins every time so I'm having a hard time embracing the "Rough" side. Although, your analogy to a golf ball has me rethinking what I think I know. Also, weren't Pirianio's comparisons between A and B carburetors done with polished manifolds?
Terry

 

[tinkirk]

Brent
??? what is the least amount of clearance between top of piston to head would be save???
Tinkirk/Terry

 

[30 Tudor]

Also, the biggest benefit I see with an aftermarket exhaust is the scavenging effect you receive with running a collector on long primary tubes. The caveat is it takes velocity to create the vacuum or scavenging effect, -which unless you are racing never really enters in. In addition to that, a Model-A has too large of an exhaust valve & port. Then, you lose the full effect of the scavenging by using the stock Model-A exhaust & muffler,

That reminds me of when I was a young guy fixing my lawn mower. So you mentioned the scavenging effect. That's a real science in two-stroke racing engines. So I thought I would push the limit on a four-stroke.

So I decided to make a race car. I milled the head off till there was nothing left but the valve chamber. Then I had to bore it deeper to make room for the valves to lift 'cause I didn't put a gasket it back on it either--I just glued the head on with coppercoat.

As for the cam shaft, I just ground it on a regular bench grinder and welded the lifters longer so I could adjust it. I made the exhaust open well before the piston was all the way down from the power stroke and didn't close it until it was starting back down on the fuel intake, then it would drop, with lots of valve overlap. Then I put a 21-in. half-inch straight pipe on it for the exhaust. When you finally got that thing started, you couldn't stop it! You could mow as tall and wet and as heavy a grass as you ever saw and it would just grind it up. I mean literally RUN through the yard, trying to bog it down. I tried and tried to just blow that thing up. Couldn't do it. It got to where it smoked pretty bad. I called it Thumper!

You know, that scavenging effect thing works pretty good. But you gotta have it revved to the nuts to work! Once it gets there, it's like a rocket!