Posted by ChadS on September 17, 2009 at 18:44:13 from (4.224.39.142):
In Reply to: Re: C-281 Camshaft posted by LarryM on September 16, 2009 at 17:10:38:
Just did one today! Took a 320ci Super M with a known M cam, put in a brand new 450 cam, picked up 11 hp, and 15 psi more cyl pressure. I have yet to to retune the carburator. This was just a quick warm up pull to retorque the head gasket, and reset the valve lash after rebuilding the entire valve train, and a few other parts,,,, LOL!
Account for lobe wear, rocker arm tip wear, even slop in the rocker arm bushings or rocker arm shaft can account for loss of power.
Take an old M cam, thats got 5000+ hours on it, the lobes can have .020 worth of wear, and be uneven from Intakes to exhaust, one cyl to the next, no one lobe will read the same.
Recondition them to factory spec, and the grind that is put on the cam, does not have to be a super puller grind, just stock and all even up to spec, and you will see a good 3-5 hp jump and a regain in cyl pressure in the end.
There is one other way to bring lifr to an old cam, rocker arms with a different ratio.
Just remember, each lobe will be worn differently, but, you will see a gain, or gain back whats lost. If you get more than what you had before,,, It cant hurt!!
Best money spent, a new cam, or a reground cam, recondition the lifters, rebuild the rocker arm assembly and dial in the valve lash perfectly.
If you got an engine thats got less than 5 hours on a fresh build, if you have only retorqued the head one time, and have not rechecked the head nut torque, you need to do this ASAP before any tuning is done. If the head is loose, the cyl pressure will fluctuate and it will run worse as it warms up. The head floats, valve lash setting go tight, loose, etc etc.
Those headgaskets are pretty thick! Takes more than one go around to get em crushed right, they will work loose!
Fresh parts, assembled and dialed in with some patience, which sometimes, I dont even have on some days,,,,,,, will be worth an extra 5 hp, or more, over your best dyno run,, just by whats mentioned above.
Want more? All the new parts will need to be tuned, matched up, dialed in.
Reconditon the governor, not turning the rpm way up, but, rated rpm. Worth and extra 2hp easy at 540, and this probably is what will unlock a massive torque curve that these engine actually do have. They will grunt with a few parts and some upgrades.
Distributors, Look over to the left of this page, all the parts you need, specs too! From parts to rebuilt assemblies.
Carburators, I was looking on this site, for a rebuilt carb, thats a good deal. Then send it over to me and Ill hop it up, or tell ya how, most Ive heard, they dont need anything but tuned in by adjustemnts,, if they need it at all. Look thru the site and price your model today!
A well built carb, a tuned governor, a good IGN, add the valve train overhaul with a new cam, shoot,,,,,,,,, Will blow nebraska test results out of the water, and help a few, trying to work some bugs out of their pride and joy. I have seen 7-15 hp more. Applications vary, be careful wear saftey glasses!
Larry, once all the math, that matters, in reconditioning parts, having done this atleast,,, once,,, If you can tell me that no stone was unturned on a build, I will have to run the follwing disclaimer, that math formula, you gave,, it aint accurate, just yet,,, there are numbers,, on the other side of the point, after that,, then that math problem is ready to be figured. What is unlikely,,,, there is no more work to do. Its called restoration, not hot rod tv.
Anybody ever see this formula in a I&T shop manual?
5hp gain easy, over anything thrown back together. ChadS
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 ]
Today's Featured Article - Identifying Tractor Noises - by Curtis Von Fange. Listening To Your Tractor : Part 3 - In this series we are continuing to learn the fine art of listening to our tractor in hopes of keeping it running longer. One particularly important facet is to hear and identify the particular noises that our
... [Read Article]
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.
