two questions

[Ratbird]

Sorry to bug you gents with more rookie questions.
first question:
I bought a used 9 inch 3rd member from Roush-Yates a while back. It's a 4.00 Detroit locker 31 spline. I used the standard Valvoline 75-90 weight gear oil. Is that what I should be using? I know it's supposed to be noisy, and I have zero experience with these things, but it sure seems to be extra clunky and noisy. Especially after I run it thru the gears, then make a slow turn or two in a parking lot. Also, it didn't come with a fill plug so I drilled and tapped one in where they normally are. (No shavings etc ended up in the unit if that's what you're thinking) I was very careful and am completely confident of that. Can you guys tell me roughly how much gear oil should it take to fill it? I may have put the fill hole a tad low so I jack up the fill side to keep it higher and top it off like that. I think it took right at 2 quarts.

2nd question:
I also recently put on Edelbrock heads. I was talking to an Edelbrock tech support guy today getting advice on metering rods etc for my 1407 Edel carb at our altitude here. The guy asked what my timing advance was. I told him the builder told me to keep it no higher than 12 degrees, however I replaced the heads since then. The tech said that because I went to the Edelbrock heads I could advance it to as high as 15 degrees. Can anyone give me a brief explanation on why that would be? I set it to about 14 and it made a big difference - really great response now. Is it possible that this will mess up my motor?

Oh, my motor is basically a 410 (416 actually), it's a 390 with a 428 crank bored .030 over. Edel 750 carb, RPM performer intake, Edel heads. FPA headers, a lunati 428 CJ cam.

thx a ton for reading my posts.

Dave Jones

[Drew Pojedinec]

nascar lockers are loud.

Older cars like mine have a fill plug in the actual rearend housing and not in the third member.

rear end lube will depend partially on your location.... ie montana vs arizona

if I remember the ford 9 takes 3 qts?  least I thought so.

with vehicle on the ground and fill plug open, I fill via a rubber hose and fill the lube directly into the vent or vent hose in the rear end (typically between wheel and third member on the driveside).  This way i don't spend an hour laying on my back waiting for stupid thick oil to trickle into a rear end, I can just flip the gear oil container over so it pours in and punch a hole in the bottom.... i'll typically walk away, drink a beer, smoke a cig, or harrass people on the FE Power forum.

[ScotiaFE]

Your in the zone at 14*.
Around 38* total advance will be good.
No it won't mess up the motor. It will probably run a bit cooler also.

[bn69stang]

Hey Dave , your on the right track and i ran the edelbrock eps 800 on my mine out the box , ran great so i leaned it out per the book and it did not like it . put it back to box stock , its been on a 434 inch fe , a 460 , and a 454 worked good on all of them .. Bud

[plovett]

Its not so much the initial timing as the total you have to pay attention to, when it comes to messing up your motor.  Of course the initial affects the total unless you change the advance curve.  As was said above, around 38 degrees is good for Edelbrock heads.  A little less is okay, too.  I usually say 36-38 degrees unless there's something unusual about the combination.

That said, more initial timing is usually better, up to a point.  You've noticed it really makes the engine more responsive at lower rpms.  Idles better, too.  I think 14 is probably good.  I would likely try a couple more degrees IF that doesn't give you too much total timing.  I run 18-19 degrees initial in my FE, but my advance curve only adds 18 more degrees so I end up with 36-37 degrees total.  So I think you need to find what your total timing is.

As for the locker differential, everybody has a different idea of what noisy/clunky is.  My Nascar take-out locker doesn't seem very loud or clunky to me.  I do hear it sometimes.  I think maybe after reading about how incredibly loud and harsh they are my expectation was that it was going to be horrendous.   Maybe the reality compared to my expectation makes it seem mellow to me?

JMO,

paulie

[plovett]

Its not so much the initial timing as the total you have to pay attention to, when it comes to messing up your motor. 
JMO,

paulie

That was a little simplistic of me.  You could have too much timing somewhere in between initial and total, depending on the vehicle combination and timing curve.  I was just trying to make the point that the total is usually the limiting factor.

paulie

[jayb]

As for the locker differential, everybody has a different idea of what noisy/clunky is.  My Nascar take-out locker doesn't seem very loud or clunky to me.  I do hear it sometimes.  I think maybe after reading about how incredibly loud and harsh they are my expectation was that it was going to be horrendous.   Maybe the reality compared to my expectation makes it seem mellow to me?

JMO,

paulie

I agree completely on the locker.  Some people are just more sensitive to the noise than others.  My "loud" lockers don't bother me at all, and I'm happy to have their benefits as a tradeoff to the ratcheting and snapping I sometimes hear from the rear end.

[bn69stang]

I guess it s a personal pref all the way around , i ll never go back to trac loc , they just dont hold up.. Bud

[Ratbird]

Thx everyone, that helps alot.
I've messed with the "all in timing" and I think I had it at approximately 2500rpm. I think it maxed out at 36ish. I'll check it again now that I'm running ~13-14 advance. I was mostly curious why it would change with the Edel heads verses the rebuilt C4AE's with the cobra jet size intake and exhaust valves. I think the builder just wanted to make sure I didn't exceed 38 total.

This rearend isn't a little noisy, it's NOISY, but only on turns - it's quiet running straight. My car is a rat kind of build with the cheapest 18 inch glasspacks I could find, thus the car is loud. Maybe it's partially because I have no carpet in the car, just metal floors. I don't mind the noise, I'm just concerned that the fluid might be low, or something is wrong with it. When I drilled the fill plug I had the pumpkin upside down with the yoke facing straight up. I used a super strong mini magnet to pull all the shavings out both while drilling and tapping. Then I rinsed it while it was still upside down with carb cleaner. That way anything that was in it flowed down with gravity. After installing it I filled it with gear oil and ran to about 20 miles. Then I changed it out again. I like the idea of filling it thru the vent tube. I read somewhere that 5 pints is good.

Bud, it's running really well right now with the Edelbrock manual's #22 setting metering rods. I like it because it's fairly idiot proof. I'll be in Albuquerque a week from today at the drag strip for the last test tune day of this season. If you're around come out and find me. I'll be there from 11ish, to 1:30 or so.

thx again to all!

Dave J

[thatdarncat]

Dave, as far as capacity my 1958 Ford shop manual shows 5.5 Pints. I didn't have a 1959 shop manual but assuming you have the original housing I think they will be the same. Sounds like you are in the ballpark. Just for discussion, the capacity varied over the years as Ford changed the design. I see 5.0 Pints in the mid sixties and 6.5 Pints in the '70's truck 9 inch rears, so anyone following this thread should check their specific vehicle. Good luck at the track, let us know how it goes.

[Ratbird]

Ha, I didn't even think of the manual Kevin. I just checked my shop manual and it says 4.5 pints.

thx, Dave

[65er]

The heads have everything to do with the timing requirement. Put simply, you want the pressure from the expanding burning air/fuel mixture to come on strong when the piston and crankshaft are ready to use that power. With older head designs the burn typically happens slower so you have to light the fire earlier.  Better designs will cause that burn to happen more quickly, therefore you will light it later in the cycle. Say maybe your total spark advance or "lead" will be 33 degrees before top dead center on better heads and up maybe around 40 for some of the old stock stuff.  What happens if you advance too far is you're pretty much applying that power to the piston while the crank arm is vertical.  With no crank angle there's no leverage and rather than getting a nice even burn pushing the piston along, it detonates in the chamber.  Detonation is extremely hard on the engine parts so that's why your engine builder told you not to over advance it.

[65er]

Here's a short camera phone video I took so you can hear my locker....

https://www.youtube.com/watch?v=Z_3YlgDqndw&feature=youtu.be

No telling how much of that sound might be coming through my brake drums, 4" aluminum driveshaft or super hard plastic suspension bushings.  Probably all are decent contributors, lol

[Ratbird]

Wade, thx a ton! The explanation on the timing helps a rookie like me a lot.

The video/audio has put my mind at ease, that's about what mine sounds like too. I'll try to do the same kind of video with my camera. Hopefully by this time tomorrow.

regards, Dave 

[plovett]

Yes, you're total timing requirement likely went down when you put on your Edelbrock heads.  Most factory FE heads will want a little more total timing than your Edelbrock heads.  Maybe 38-40 degrees.  Factory FE combustion chambers vary a lot so take that just as a rule of thumb. 

If you can increase your initial timing and shorten your curve so that the total timing stays in the in 36-38 range, the effect can be fairly dramatic.

JMO,

paulie