Unstyled A cam timing

[Another JDA puller]

I was wondering if anyone had any magic number to degree the cam to. I've heard 106 to 110. I'm at 111. It is 380 something cube with 10% over cam. I can get the degree to 106 pretty easily by shimming bearing race on flywheel side. I understand if I advance further that will give me more lug power. What will that do to power around 1000 rpm. Thanks.

 

[Mike N Mo]

I"ve never heard of a "10%" over cam. If it"s something other than a stock spec regrind you should have received a cam card with the specs (intake duration, exhaust duration, lobe seperation angle and intake centerline). I"ve had 2 cylinder cams spec-ed from 103 to 107 degrees on the intake centerline, depending on the specs for that particular cam.

Mike

 

[buickanddeere]

Nothing to gain by shimming or advancing/retarding by a tooth with an old worn cam.
Send the cam and followers to a reputable shop .with all the engine data such as bore , stroke, head/port work, mechanical compression ratio, desired rpm and octane of fuel to be used.

 

[Another JDA puller]

This is a reground cam I installed 7 years ago. I degreed it to 110 centerline at that time. The card that came with it doesn't say what to install it at. I ordered it from Berry's and is supposedly what I need for my tractor based on info I gave them. I told them I run 1080 rpm limit and they called it a 10% over cam at the time.

 

[Anonymous-0]

By 10% over they must mean a cam thats good for 10% over on rpms?

 

[Another JDA puller]

Yes, I tried finding out what to degree cam at at the time but between me buying the cam and installing the new owner did't know anything about it only how to run the grinder.

 

[Mike N Mo]

If you still have the card post the intake duration specs @ .050 lift, and I can compare it to the cams I've had over the years. I should be able to give you something close for an intake lobe centerline spec.

Mike

 

[north puller]

I have a 70 with the Cam degreed to 109 if i remember correctly. It runs really good from stock up through 20% over, but dies off fast below stock rpm. I would advance the Cam more than that. I would try 106-105 if you're running 10% over or less.

 

[Another JDA puller]

Cam specs are .365 lift at cam both lobes.Advertised duration is 264 on both lobes. duration is 194 int. 208 ex. @ .050 lift, 110 lobe separation.

 

[Josh Blackburn]

Before your unhappy with the performance I would order a new cam. That cam will fall to 750-850 rpm instantly with my experience.

 

[Mike N Mo]

I've never installed a cam in a puller with that short of [email protected], so I don't have anything close. I find it somewhat surprising that both lobes have the same lift, same total duration, but have 14 deg difference on the @.050 lift. I'd be tempted to put it at 106-108 degrees. Only a dyno and some time will tell you for sure.

Mike

 

[Another JDA puller]

That's the way it's always acted. Depending on where I pull sometimes I could run 2nd 3.5 mph 4500-6500 and every class it would stay at the same rpm, around 800 or so. I probably won't change the cam until winter, I have some pulls coming up shortly. But I would like to improve what I have now by retiming. If I advance what I have now, will that possibly increase my hp at the rpms I'm used it running or will the rpm range go lower? Who would you recommend for a cam grinder? Thanks.

 

[Anonymous-0]

Your cam is crap. Throw it away and get another with more intake duration and less exhaust duration.
Why do pullers pay good money for these junk unproven cams? To make any antique tractor run good you need more intake duration and less exhaust.

 

[Josh Blackburn]

You can play with cam timing but I highly doubt you will see much gains. It's just not a good design. I can grind you a cam in house that will wake that tractor up tremendously. If it were me i wouldn't wait til winter, it's a weekend Job and you could have twice the tractor. I've been there. Just my opinion

 

[Earl-IL]

Josh,Give us a update on the "G".

 

[Josh Blackburn]

Opening plug gaps helped a little when warm. Tractor makes lots of power but lopes below 3/8 throttle putting a small load. Til full load is on.

 

[Earl-IL]

Thanks, Do you have any unstyled "A" cam cores ground up? My email is open can you send me your phone number?

 

[Another JDA puller]

What's the price? Do you have any ready without me getting you my core imediately? I won't have my head back until the 12th, so I have some time. 7.25 stroke x 5.75 bore, 9.4:1 comp. unstyled head with 1/8" bigger valves.

 

[2-banger]

lope..lope..lope..lol mine hops

 

[2-banger]

ive got joshs cam in my late a...runs good..

 

[Josh Blackburn]

Lol

 

[Another JDA puller]

What's your contact info, I'm interested.

 

[Josh Blackburn]

Yes call me 9892775366