Serpentine belts

D

Dave moly

New member
Can anyone tell me how fitting a serpentine belt to a model a can give it an extra 10% horsepower as claimed by Snyder’s
 
10% equals 4 HP, I find it a bit hard to believe a serpentine belt would make that much difference. A properly tightened V belt on a Model A will be quite loose compared to V belts on modern equipment. A cog belt is supposed to take about the same HP as a serpentine so might be a better option for a stock A. A serpentine belt has more contact area so will run a heavier load, not a problem with a stock A. I'm not an expert, just my understanding, take it for what its worth, probably less than 2 cents!
 
I think it's the fan blade more then the serpentine belt. The two blade fan probably moves more air therefore uses more power then that plastic 6 blade fan.
Just my 1 cents worth.
 
Just speculating but with the plastic fan they flatten out at higher speed so it does not take a much HP to turn but I don't see it increasing HP 10%. Also as the fan flattens out it allows for better air flow thru the radiator.
 
You will notice that modern cars with serpentine belts run spring loaded idler pulleys to keep constant tension or preload on the belt to prevent slippage. How much belt tension can a Model A water pump take, and for how long?

As far as the claim of 10% more power, without a notarized dyno sheet, it did not happen!
 
All I can say is its a slippery slope...first its a plastic fan and serpentine belt,then you put on a B carb,then a high compression head,then a weber carb with an FSI,an aries muffler and mitchell OD..convert to 12v..then thats not enough so you pop for a B block with a Serr head,juice brakes and an f100 steering box..then one day,in a moment of sobriety you look at the car and wonder where the model a went..
 
Jack Shaft said:
All I can say is its a slippery slope...first its a plastic fan and serpentine belt,then you put on a B carb,then a high compression head,then a weber carb with an FSI,an aries muffler and mitchell OD..convert to 12v..then thats not enough so you pop for a B block with a Serr head,juice brakes and an f100 steering box..then one day,in a moment of sobriety you look at the car and wonder where the model a went..
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While I understand what you are saying here, Jack, I shake my head at those guys who build a hot rod with an auto transmission, Chev 350, Jag rear end, hydraulic brakes, independant suspension and modern steering, yet still call it a Model A. Ebay is full of them.
There is a rule here that says that to call a car any particular model, it must have 5 of the 7 major components that came with that model and the others period correct. he 7 components are:
  1. Chassis
  2. Engine
  3. Radiator
  4. Gear box
  5. front axle
  6. rear axle
  7. steering column
I find it interesting to note that the body is not included, yet parts of that is all some of these rods have from the Model A
As far as I'm concerned, I'm happy if someone is using their car with the modifications you mentioned rather than either cutting it up for a hot rod or leaving it rot in a shed.
 
I like model a fords and I like the people who like model a fords for the most part.My point above was to make light of the quest for speed.If a person decides to buy one of these cars he's entitled to do as he wishes with it here in America,hell he can fill it with concrete and use it as a doorstop if he wants. I spent a few years of my life defending that right.
 
I bought a model A because I wanted a model A. I will keep it a model A because of the fun driving it with all the model A nuances.
 
I'm not sure of exactly what Snyder's sells with their serpentine belt, a system? At least part of the HP gain is from the extra flexibility of that belt, more flexible = easier to turn the gen & fan. I've been involved in dyno testing of performance A's, one time we took the belt completely off and I turned the water pump with a hand drill while a dyno run was made. From memory that was 3 HP. Don't recall if it had a serpentine or not?
 
I agree with jack shaft , waited 40 years to get a model A, and wanted to have a car close to original as could be.
The engineering is fascinating, and enjoy making machines work, was a Ford tech for 40 years and saw so many changes over those years.
 
Jim Brierley said:
I'm not sure of exactly what Snyder's sells with their serpentine belt, a system? At least part of the HP gain is from the extra flexibility of that belt, more flexible = easier to turn the gen & fan. I've been involved in dyno testing of performance A's, one time we took the belt completely off and I turned the water pump with a hand drill while a dyno run was made. From memory that was 3 HP. Don't recall if it had a serpentine or not?
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Haha, If you took the belt completely off it wouldn't make much difference if was serpentine or not. :p:p

Fine print: Sorry Jim, I mean no disrespect. I'm bored from "staying home" as ordered by the State of California. Time to go outside and inspect my nut & bolt collection again.

Stay Safe Everyone
 
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Yes, Jim left his rear-end out in the air on this.

I take it as more of an observation that this particular motor/dyno/configuration showed only 3HP increase by completely removing the drag from waterpump/gen/fan.

Personally I find the ads claim to be pretty optimistic at best.
Before anyone points out the fact that I have one on current coupe, it was put on for the plastic fan as it can take higher rpm.

John

PS, yes, getting cabin fever, need to go for a therapeutic drive in the hills
 
I don't put my diff out in the cold in this kind of weather!!! The idea was to show the total power used with the belt on. Don't over-think the situation! -:) If the total used is only 3 HP, it is doubtful that Snyders system can save 4 HP
 
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Too the point where is energy being lost? the belt is thick and it takes energy to bend and straighten out (think about bending a piece of bailing wire fast: gets hot.) 2nd. belt jams itself down into the V of the pulley then has to pullout. More heat. Then add the Generator, tighter bend and another in&out. Might be some Horses eating hay. Surpentines bend with no real force and do not jam into the v to get a grip.
 
I used to write ads for speed equipment manufacturers. Wrote an ad for headers and since it was the seventeenth of the month, I claimed that the headers were good for 17% more HP. This ad appeared in CAR CRAFT and HOT ROD. Received a letter from the feds asking for proof! To make a long story short, don’t believe any sort of HP claim that you read! One exception is Jim Brierley’s HP claims for his heads and cams!
 
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