more power from jd a

[OleJohnny]

This has probably been beat to death over the years but I am a new reader and new to antique tractors so I would like help.
I have a 1945 JD model A that is in stock condition that I would like to make more power to pull. I dont want to spend the 4000.oo for a big bore motor or things like that but I would like tips and tricks to make it have more 'grunt' when the sled clamps it down. It runs out of power before it spins out in the 5000 class. I run in low gear so that isnt an option ether.

 

[johndeereman]

Sounds like you have the cast all fuel pistons still you can over bore it and put aluminum high compression pistons in it that should get you enough to spin out but depending on class rules you probably won"t really be competitive for that you"ll most likely have to power block it or stroke it

 

[OleJohnny]

Can the pistons be put in the engine without the front of the tractor being taken off? I/E while the frame rails are still on?

 

[OleJohnny]

Also, If i should come across a power block, what must be done to install it? Again does the front of the tractor have to come off and does the power block use the same rods and only different pistons?
Any help you guys can give me is appreciated..

 

[showcrop]

If the objective is to pull for low dollars get a Minnie Moe or an Oliver or an Allis. It takes a lot less money to make them competitive. If it is your great uncles so you have to keep it and run it, just be patient until you have the big $$$$ to put into it.

 

[johndeereman]

You need a 6-2 power block you use the same rods no need to tear any of the tractor apart except the engine pull the head unbolt the block bolt new one in I run high compression pistons in mine from Tripple g services

 

[VicS]

JD's are easy to work on unless you want to put a different Cam in. No the head and block will sneak out with out even taking the hood off.

 

[randy hall]

to install a power block you put the pistons and rods in the block and then slide the block in place no takeing the front frame off. same rods. different block and pistons.

 

[2-banger]

i dont know where your from but i wouldnt go to triple g..if your in ny i can give you # of shop that does triple gs work. id bore block .125 over and put al pistons in it..have head milled .150 and do some hd work(grind eye brows out) ,gasket match manifold, get a good gas manifold, send your rockers to josh blackburn and let him ratio them. your a should make around 50 hp and will run good. to go one step further let josh lengthen your rods a little to raise compression..if you can get it to around 200psi it will really run. without doing rods you will be around 150psi

 

[2-banger]

id also get a later a carb (71) if your still using the orginal 53

 

[Mike N Mo]

JohnDeereMan, If the origional poster has a '45 A, he would need a 6-1 powerblock. I've seen 6-2's in an early styled A (<584,000), but it's a lot of work. 6-1's fit unstyled (using a styled head) thru 583,999, 6-2's fit 584,000-647,999, and 6-3's fit 648,000 and up as well as 60's. Just wanted to clear up that bit of confusion. Mike

 

[Mike N Mo]

2-banger, instead if getting new pistons, lengthening rods, and milling the head to raise compression, doesn't it make more sense to just get custom high compression pistons and get the compression where it needs to be with one part? Seems to be a lot simpler. Mike

 

[BushogPapa]

Consider putting a Longer Stroke in it...8 1/2" or 9"..and bore it 1/8", to get good bores..
Then, you are prepared, should you decide to add more power later..it will Lug Much better and last.

Ron..

 

[Loosehandle]

I would recommend getting a later model with the slower speed trans.

 

[buickanddeere]

Compression, cam and port cleanup.
The old cam and followers have to be licked after these many years. Would not even make factory HP even if everything else was brand new.

 

[2-banger]

id bore it .125 over ..custom piston will cost more than doing rods and al .125 over pistons..ive priced them..this is what we did to my 60 and its a beast...and iam building a late a now same way but with offset crank.

 

[OleJohnny]

I understand that a 'power block' is longer cylinders' but unless the crankshaft is stroked, how could longer cylinders make more power with the same stock stroke??

 

[jd b puller]

- Sleeves are not longer on a powerblock, they are bigger in diameter.
- Bigger diameter = more cubes = more power.
- Powerblocks also had higher compression and aluminum pistons = more power.
- I"d much rather stroke one than put a powerblock in ($ for $, much better value vs. HP gains
- Powerblocks can make you bump up a class, stroke will not.
- Stroke adds torque, cubes, and power
- Offset grind is a waste of time
- The "high compression" pistons you find commercially available, mean high compression for 1960 farmers, not a puller.
- Cams are a great add, but a PITA to change
- Fuel choice will dictate how high you can go on compression.
- It takes good parts (that doesn"t mean expensive) to make good power. You can make so-so power with mediocre parts.
- Don"t just throw something together and see how it runs.

 

[OleJohnny]

See,, I'm learning all the time. How large could I bore out the original sleeves and install larger pistons and save the money of the new block??

 

[2-banger]

u can bore a block to 5.75 and use air plane pistons or get pistons from extreme

 

[OleJohnny]

AIR PLANE PISTONS???? R U just kidding??
Will the cylilnders go out to 250/000 over stock? That sounds like alot.
Im just trying to get enough power to pull with the other 5000 pound antiques around here, I think if I had pistons that wernt the 'multi fuel' low compression slugs,, it might be cdompetetive.
I have built several drag engines over the years but never had a JD engine appart.
Someone give me a place to purchase budgett parts to play. Pistons? Power block and pistons? Carburetor and manifold?
I truly appreciate all you guys helping me.

 

[OleJohnny]

I have another silly question. From what I have seen of the cylinder heads on the JD engines. They are flat heads. Why do people say they 'cut' the heads to make more cmpressioin?? If you cut something that is flat, it isnt changing the head volume.

 

[2-banger]

51 a iam builbing is 5.75..i got airplane pistons josh blackburn made toofit block..i bought murphys manifold..had josh open up a 71 carb..josh did rockers and rods..i had a local shop offset grind crank. josh did cam for me also..we do your own heads on all the tractors..id talk to josh it all depends on how much you want to spend..i didnt want to spend alot..extreme tractor ..ray makes nice pistons for a..i wouldnt spend the money for a power block..like ray said id go with stroke over the pb my emails open if yu want to talk

 

[2-banger]

i dont think your 45 a will have a flat head? when i say cut eyebrows out thats on a cyclone head

 

[ferry brothers]

how mutch do you want to spend ?
100$
1,000$
10,000$
how much more power do you need ?
5hp
10hp
50hp
100hp
more than likely stroke it.

 

[JLO]

We have a head that should bolt on. That has been professionaly ported and polished with big valves. It is for sale

 

[OleJohnny]

If I can make 10 or so more hp with a bolt on head or put in high compression pistons of standard bore, this sounds like what im hoping for. $10,000 is wayyyyyyyyyy out of reason. closer to 1,000 or 2,000 is more what i hope to find.
That is why i ask how much the stock cylinders can be bored and if someone sells high compression pistons to fit standard bore and on up to gain the power. Has anyone got any suggestions of advancing or retarding the timing to gain alittle power? It is on 25' now.
Hey! How much for the head and what do you think it would give?? Where are you located also??

 

[OleJohnny]

Im not gona spend nor do I have 10,000 dollars to put into a 2000 dollar tractor to play alittle. I would like to simply have enough power to atleast pull with the other 5000# stock tractors. I dont expect to win but I would like to make a good showing. It now has the multifuel low compression pistons in it so that is why my first thought was high compression pistons and etc.

 

[Pmer]

If you had all the parts ready to stroke a model A how long might it take to complete the job?

If you did it once before, take it apart and put it back together

 

[toot]

What size tire are you running? Is it a "stock class" with uncut rubber? How far are you distance wise to the winning footage before you power out? Will this tractor be strictly for hooking to a sled only? And finally, what is the roundabout sled chain length and drawbar max height where you pull? That would help my answer a lot to you.

 

[toot]

1939 and older A tractors had the flat heads. Your head has a chamber and you could mill it say like .150 to gain a little compression.. or use the head from a late 47 to 52 model A which already has a smaller chamber from the factory. Feathering back the eyebrows which shroud the intake valves on chambered heads helps some as well. Head cutting, match porting, valve bowl work, and eyebrow feathering help altogether, but wont get you where you need to be.

 

[OleJohnny]

It is an antique stock class with NO CUT TIRES, I am allowed 15.5x38 tires (which I have) the hitch height is 18 or 20 inches ( depending on locatiion of pulls). It is for antique tractor parades and pulls and tractor rides on back roads occasionally only (no field work)
My max pull seemed to be around 200 feet and no spinning and only slight front end lightness.
Like I said earlier, it still has the low compression, multifuel pistons in it.

 

[OleJohnny]

Has anyone ever adjusted the timing on one of these low compression motors to find out if advance or retard help it??
My engine is running at 25degres now (stock setting that I checked with timing light).

 

[OleJohnny]

how can I get in contact with you about the head???

 

[buickanddeere]

You will be happy with the price and power with just high compression, a cam, port/manifold cleanup and a race quality valve job.
Just ask your cam grinder what compression ratio that will run on 93 octane pump gas in a pinch and usually on 100LL.