JD A rpms?

I'm just getting into pulling (pulled twice, got spanked both times) and starting to do little tweaks to my tractor here and there as money becomes available so I swapped the primary reduction gears in my '48 model A with a set from a '51 and I'd like to get a few more rpms out of my engine to get my ground speed back up. What's the best way to go about doing this but still keep the ability to kill the engine by pulling the throttle? One guy told me to bend the governor spring but I'd like some other opinions before I modify anything. Thanks

Find another governor spring and add it behind yours.A shorter spring works best. One from an A or B will bolt in the bracket with yours and will increase the pull on the governor,but will be the same at low throttle.Good Luck!
Also might want to remove the cap on the air intake stack(punch loose rivits),and look down the intake stack for hornet nest mud. This will really cut down horsepower and can be cleaned with shop vac and bar to chip it loose.

(quoted from post at 13:05:27 07/30/12) Find another governor spring and add it behind yours.A shorter spring works best. One from an A or B will bolt in the bracket with yours and will increase the pull on the governor,but will be the same at low throttle.Good Luck!
Also might want to remove the cap on the air intake stack(punch loose rivits),and look down the intake stack for hornet nest mud. This will really cut down horsepower and can be cleaned with shop vac and bar to chip it loose.

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Thanks! I like that idea much better.

One of my few tricks is to back the spring with a 3 inch long piece of 1 X !/8 HRS flat strap slotted on one end to fit on the bracket with the regular spring to stiffen it's "give" some....works good, peps up a "lazy" John Deere pretty good for me.

(quoted from post at 01:28:20 08/01/12) One of my few tricks is to back the spring with a 3 inch long piece of 1 X !/8 HRS flat strap slotted on one end to fit on the bracket with the regular spring to stiffen it's "give" some....works good, peps up a "lazy" John Deere pretty good for me.

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Another excellent idea. Thanks! I like the idea of it being a bit adjustable.

How far should I consider going with the rpms on a basically stock motor? I was thinking around 1200.

(quoted from post at 21:09:03 07/31/12)

(quoted from post at 01:28:20 08/01/12) One of my few tricks is to back the spring with a 3 inch long piece of 1 X !/8 HRS flat strap slotted on one end to fit on the bracket with the regular spring to stiffen it's "give" some....works good, peps up a "lazy" John Deere pretty good for me.

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Another excellent idea. Thanks! I like the idea of it being a bit adjustable.

How far should I consider going with the rpms on a basically stock motor? I was thinking around 1200.

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Most pulls allow 10% over stock, so 1200 is too high for an "A".

Most pulls allow 10% over stock, so 1200 is too high for an "A".

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If I ever join the local pullers club and beat anybody then someone might care enough to send me in for an inspection but since I don't belong to the club (or ever beat any of them) my pulls don't effect them. I just want to get the sled a little further down the track for the crowd.

(quoted from post at 14:34:21 08/01/12)

Most pulls allow 10% over stock, so 1200 is too high for an "A".

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If I ever join the local pullers club and beat anybody then someone might care enough to send me in for an inspection but since I don't belong to the club (or ever beat any of them) my pulls don't effect them. I just want to get the sled a little further down the track for the crowd.

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Be that as it may. 100 or so rpm's is not going to help you much, towards your goal. Getting the tires hooked and the weight in the right place will do more and be cheaper. Just saying. Just cause Deeres are handicapped in RPM doesn't mean you need it to win. A late "A" has 321 cubic inches stock vs 281 in a 450 Farmall for example. The "A" is also better balanced than the 450. If your not at least placing with an "A" vs Farmalls and others. You've got more problems than 1 or 2 hundred rpm's will fix.

I'm running a 251 CI Case that's is doing extremely well against 6cyl Olivers ond Cockshutt's, not to mention Farmall's of all sorts.

The secret to success is taking care of the small things first. Balance, Tires, Tire pressure, Hitch height and placement. Losing 2 psi in the rear tires took me from 3rd place finishes to first place in three classes last Saturday.

Just for reference I've pulled on three different dates for a total of 11 pulls and have four 3rds, one 2nd and five 1st place finishes. Never pulled before this year and only those 3 dates mentioned above.

I'm dang proud of my accomplishments, and took a lot of time to study what others were and weren't doing, before I even started on the brackets and hitch. At our local club, I always volunteer to be the flagman for the first part of the event. It allows great insight into track condition,how a winning tractor is set up, and where to take the sled when I pull. Winning takes more than a hopped up tractor.

Off my horse now. Have fun!!

(quoted from post at 01:28:20 08/01/12) One of my few tricks is to back the spring with a 3 inch long piece of 1 X !/8 HRS flat strap slotted on one end to fit on the bracket with the regular spring to stiffen it's "give" some....works good, peps up a "lazy" John Deere pretty good for me.

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Dukester, its been almost a year but I finally tried your trick and it worked like a charm. I haven't put a tach on it yet but it sounds like its running more like its supposed to. Thanks again.

Borrowed a snout tach and put it on the A. I had it turned up to where the cadence about matched my G and it read just under 1000 rpms. I'm estimating that it was turning around 850-900 rpms before the backing plate was added to the spring. I turned it up to 1150 and called it good. Thanks again Dukester.