Offset Grind 226 crank
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=178459
Printed Date: 08 Sep 2025 at 5:57am
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Topic: Offset Grind 226 crank
Posted By: JMetzner85
Subject: Offset Grind 226 crank
Date Posted: 19 Feb 2021 at 1:45pm
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I plan to have my 226 crank offset ground for d-19 gas rods. That will give me a 4.875 stroke. Can I still run straight WD Pistons to get increased compression, somewhere up around 12:1 or 12.5:1. I also think I may have a parts WD with a set of M&W pistons in it, it is a 201. Would I be able to run those also?
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Replies:
Posted By: DrAllis
Date Posted: 19 Feb 2021 at 3:20pm
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M&W's from a WD (SP-46) won't even work with a stock crank without machining .170" off the tops so they don't hit the cylinder head. Regular 4 inch bore WD pistons should work but I can't tell you what the comp ratio will be without piston height specs, because there is more than one WD piston.
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Posted By: JMetzner85
Date Posted: 19 Feb 2021 at 3:39pm
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Dr Allis thank you for a reply, what is a somewhat safe compression ratio for my pulling tractor (I am fine running race gas), using an offset ground crank and buda rods?
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Posted By: DrAllis
Date Posted: 19 Feb 2021 at 5:14pm
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You're not going to hurt the rods. They are 14 or 15 to 1 in the diesel engine. Racing gas varies in octane rating. One of my first pulling engines would compression test at 240 psi per cylinder and I got by with 108 octane gas. My current engine is higher ( 300) and takes 114 octane. You need a good timing light and mark the flywheel for 20 degrees BTDC at 2,000 RPM, because you'll need to be down around there with high compression, not 30 degrees like your flywheel may be marked now. Dyno tuning is the best for timing and then figure out what it is 18 degrees or 20 or whatever. You don't say what chassis or which 226 engine.
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Posted By: JMetzner85
Date Posted: 19 Feb 2021 at 5:43pm
Dr. ALLIS, I'm going to build this out of several different engines that I have. It will be going in a WC with RC ring and pinion,with non cut 14.9x38s. What is the best way to get a better timing mark on my flywheel? If I remember right, I don't recall seeing a mark on my flywheel at all.
On a different note, is there anything I should do as far as degreeing the camshaft? And would you recommend a different grind at that compression ratio?
I want to tell you thank you again for your responses, it's not just anywhere you can get this good information.
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Posted By: DrAllis
Date Posted: 19 Feb 2021 at 7:52pm
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The marks on the flywheel are intended to be straight down at 6 o'clock to be read for a WC/WD/WD45 chassis. The TDC mark and the FIRE mark are 30 degrees apart. Using a tape measure you can find half of 30 is 15. Then, you make two marks between 15 and 30 which would be 20 and 25 degrees BTDC. I give no cam degreeing advise. I just use a 175 grind, which can be done to your camshaft for probably $350. I sure hope you are using a WD45/D-17 manifold and carburetor ?? at a minimum.
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Posted By: JMetzner85
Date Posted: 19 Feb 2021 at 8:26pm
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Thank you for the advice once again. Yes, I have a wd45 carb and manifold. Do you do machine work and build engines also? If so, where are you located?
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