Welcome! Please use the navigational links to explore our website.
PartsASAP LogoCompany Logo Auction Link (800) 853-2651

Shop Now

   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver

Tractor Pulling Discussion Forum

J D G head work

Welcome Guest, Log in or Register
mike melvin

09-16-2006 14:55:49

Report to Moderator

Wondering what could be done to a G head. The block was bored 125 over and 7 5/8 stroke. Had the cam done by Roberts. What valves to use in the head and other stuff done to the head.Any suggestions would be greatly appreciated.

[Log in to Reply]   [No Email]

09-17-2006 05:59:27

Report to Moderator
 Re: J D G head work in reply to mike melvin, 09-16-2006 14:55:49  
there's really not a lot to be gained. you're just 58 cubic inches over stock. to maintain torque you don't want to go crazy, maybe just a little smoothing out of rough and sharp edges. I wouldn't put larger valves in.

[Log in to Reply]  [No Email]

09-17-2006 13:16:52

Report to Moderator
 Re: J D G head work in reply to murphster, 09-17-2006 05:59:27  
You have 58 ci more to fill than before.Can we assume that the induction system on an ole G was "over designed" with future mods. in mind??? Also, any slowing of inlet flow velocity caused by "opening" things up a little has allready been more than allowed for by the large increase in stroke.Longer stroke greatly increases the intake and exhaust velocity. Put the G on a good hard pull,and after 15 min,take a plug reading.Use this to get your fuel mixture spot on.Without spending a lot of "experimental" money,I would get your carb,governor and spark dialed in perfect. Rather than the expense of larger valves and cams to fill the extra cubes,heres what I would do.Check the piston to valve clearance. There should be way plenty.(use modeling clay on top of piston and roll engine over 4 revolutions,measure thickness).Have a GOOD machinest alter your rocker arms ratio to open the valves farther (even .050 will pass a lot more air)We are talking a 2 cyl tractor here,that won't see 1500 rpm.This little mod makes more sense than spending the money on cams and larger valves to do the same thing. Stick to the basics and use common sense,that's the secret to getting torque out of these ole 2 cyl's. A little extra compression is another by-product of stroking an engine. Check your new compression ratio.If it is getting up in the 9:1 or higher range,then you can also now take advantage of the higher octane,longer and more powerfull burn of a 94-96 octane fuel. It all adds up! Torque +

[Log in to Reply]  [No Email]
[Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:

We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]

Home  |  Forums

Copyright © 1997-2023 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters

Website Accessibility Policy