Pulling Forum - Hot Rodding a WD45

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Hot Rodding a WD45

Printed From: Unofficial Allis
Category: Other Topics
Forum Name: Pulling Forum
Forum Description: Forum dedicated to Tractor and Garden Pulling
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=174643
Printed Date: 23 Nov 2024 at 12:19pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: Hot Rodding a WD45

Posted By: WD45_Guy
Subject: Hot Rodding a WD45
Date Posted: 24 Sep 2020 at 3:10am

Hello Gents,

I have recently acquired a WD45 Narrow Frontend. Other then paint it’s a superb tractor. My main goal is to just restore it to have for parades and to ride around on. I then got thinking about the local tractor pulls and one of the guys at work who pulls talked me into doing the antique tractor class.

Anyways what all can I do to help the old gal have a little more umph? It’s still 6 volt positive ground and it starts up instantly, and runs well as it is.

I wanna stay 6 volt so bore and stroke and high compression isn’t in my realm of want. Nor am I looking at being overly serious in pulling. I just like to tinker and make extra power when I can.

Anyways any and all tips or tricks would be appreciated.

Replies:

Posted By: WF owner
Date Posted: 24 Sep 2020 at 6:31am

If the engine needs rebuilding, use a D-17 overbore kit (4.125" vs. 4/0") and 7.5 / 1 compression pistons. (8.25 / 1 pistons are around, but scarce and pricey !)

Improving the flow of the manifold makes a big difference on the 226 engine.

A bigger, or improved carburetor will help.

A governor spring from a D-17 will give you more RPM's.

If you are going to stay 6 volt. make sure your battery cables are big enough and all connections are clean. Six volt is much less forgiving than 12 volt.

After you get it running, a good (adjustable) hitch, custom built for tractor pulling and tires will make the most difference in how well the tractor pulls.

Posted By: DrAllis
Date Posted: 24 Sep 2020 at 6:37am

Get yourself a twine string about 8 ft long and tie it securely to the vertical governor arm behind the generator. Hook to the sled and place the tractor in LOW gear. Tighten the chain and ease out on the clutch. Pull the hand throttle wide open. Pull on the twine string until you think it's going to fly apart. Release when the pull is complete. In good tune, the tractor will have 43 PTO HP @ 1400 RPM. If you double the RPM to 2,800 (very easy to do) you will have effectively 86 HP @ 2,800 RPM.

Posted By: WD45_Guy
Date Posted: 24 Sep 2020 at 4:44pm

Thanks for the reply guys. The engine runs strong and I don’t think it needs a rebuild but I’ll keep in mind the D17 kit. I was looking at governors and some say Gleaner E some say D17 are the best. Which would better? Also what is a better free flowing carb that I can install?

I appreciate the info!

Posted By: DrAllis
Date Posted: 24 Sep 2020 at 5:27pm

The only difference in a combine governor to tractor governor is how quick the weights react to a load. The tractor governor has about a 300 RPM droop to full load and the combine governor is about 150 RPM droop. Carb size increase can be a nice performance enhancement with a D-19 , Oliver 1650/1655, or MM big 4-banger size carb Marvel Schebler brand carb can be worked over to fit the manifold and governor linkage. The throttle plate bore is as large as the manifold inlet hole, unlike the OEM WD45/D-17 carb. A larger CFM carb is the only thing you can do to really increase HP and torque. No amount of fine-tuning will increase the power output more than 43 rated PTO HP @ 1400 RPM. When tractors were tested at Nebraska Test they were tuned as well as they could be. Advancing the ignition timing will get you nothing. There are after-market rocker arms that open the valves a little farther that I'm told are good for 2 more HP.