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Discussion Starter #1
Hiya...well I am breaking in my new rebuilt S code 390...running good...but pretty loud at around 18-22K rmp...As far as I believe, the rocker setup is a non-adjustable setup? It is a stock '68 390 rebuild....10.5:1, mild ISKE cam, a little beefier springs...that is it. Are these motors notorious for having loud rockers? It seems like the noise is louder when the motor is just cruising or decelerating. I was thinking of putting in these..

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=34202&item=2409955023&rd=1

What do you guys think? They have a $100 reserve....wise choice? Thanks
Chris "bark the tires" D
 

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Discussion Starter #2
Jesus, any engine would be loud at 18-22K rpm...I'm talking 1800-2200 RPM....
Chris "ridin' the short bus" D
 

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Discussion Starter #3
Royce? Bueller?
 

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This is probably a stupid question but, do you have plenty of oil pressure??
My 390 is pretty quiet, the fan is the loudest thing under the hood..

Bruce
 

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Discussion Starter #5
Huh

Yah, oil is fine....75lbs going down the road....all full...everything else is working fine...my 72 ford P.U. with the 390 has a pretty quiet motor...so don't know what the deal is with this one...
 

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ockham's razor

Hey short bus :D
Since the engine is still being broken in, try readjusting the rockers if you have a hydraulic lifter setup.
Sometimes hardware do strange things.
You may just have a nut that backed off.
Hey, a set of v/c gaskets is cheaper than rocker arms and v/c gaskets!
:alien:
 

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Rockers

I have Erson rocker setup on one engine, it is probably the best available.

Stock adjustable assemblies are around $175 a set brand new, you have to change pushrods also. Pushrods are about $50 to $100 depending on brand for a set.

Erson rocker assemblies are around $625 a set.

Typically you need to install adjustable rockers on a rebuilt 390. It is difficult to compensate for all the variables to get the non - adjustable setup to work on a rebuilt engine if any of the machining is not compensated for in some other manner.
 

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Discussion Starter #8
Ah...

So that setup of the adjustable rockers is not all I would need....I'd have to buy new pushrods too? Then it would probablly pay to buy a set together instead of rockers from here and pushrods from there. Where may someone (such as myself) buy the stock adjustable rockers and pushrods? Don't know if I can afford the Erson ones...Royce, do you happen to have a picture of the ones you have? I want to thank you all for the advice....once again.
Chris "barking in bakersfield" D
 

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Chris,
The place for you would be DSC Motorsports in Victorville I believe.

http://www.dscmotorsports.com

Dennis Carrico is the owner, good guy.
 

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Chris,

Royce is the expert and I am not.

That said; when I have rebuilt 390s I usually ended up with pushrods that were now "too long" due to the milling of the deck and heads. As a result the engine would back- fire like crazy as the valves couldn't quite close. Then I would shim up the the rocker arm posts until the back-firing went away and things sounded OK. Not technically correct, but very affordable.
 

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Discussion Starter #11
Interesting

To hear about that problem (too long)...that would have never occured to me as a potential problem. I know mine is the other way though and a little too loose....it's nothing way to obnoxious, but I would like to fix it to avoid future problems so I will more than likely go the way of adjustable rockers. It's a completley new motor, minus crank and block/heads....pistons/cam/rockers/etc./..all new. So I am on the quest for adjustable rockers/new push rods for those rockers. Thanks to all for the help and I'll be asking questions soon!
Chris
 

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Don't really know if this would cause noisy rocker's, but are the rocker stand bolt's in the right hole's, theres one with a oil passage that take's what look's like a shoulder type bolt. Been so long since I really got into one. Double check with Royce or someone who get's into there motor's more than I do. Just a thought.... Jon
 

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Discussion Starter #14
Engine was totally assembled

When I got it back (well worth the $200) I didn't know about the different rocker shaft bolts..if there is something to lookout for, let me know...I can take the covers off and check. I don't think they took too much care in making sure the bolts were in the exact place that they left the motor. I'll check out that website now, thanks guys!
Chris
 

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And on the question in the first post of whether 390's are noisy engines, some years ago I managed to get to work on a low mileage example that had never been apart. It was electric-motor smooth and quiet. Very similar to a late model 4.6.
 

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Discussion Starter #16
Ordering them

Thanks for the advice....I am ordereing the stock type adjustable rockers and pushrods for a total of 280 or so...not bad to have a nice silent motor....this site rocks
Chris clackity clack clack D
 

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The engines are not noisy somethings wrong. What about the rocker shaft is it upside down and is the oil hole restricted? You can get diff size pushrods. Thats the correct way of adjusting FEs like this one. Its also important to have the tapewred bolt in correct hole and all pushrods need to match pedetsals.
 

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Was the cam broken in properly? And tapewred is supposed to be tapered.
 

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Discussion Starter #19
I think so

I did what the engine company told me...first time the motor fired up, went straight to 1800 rpm for about 10 minutes. Do you happen to know which bolt hole gets the tapered bolt? Having stronger springs wouldn't cause noise, would it? I'm hoping this is something that can be fixed with adjustable rockers. If I were to just use longer pushrods...the lifters would compensate for the rods that are longer than necessary? Like mentioned before, it's not an obnoxious constant clacking, just around 2K rmp and not under much load....but enough for me to want to fix it...hope I can
Chris
 

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Sounds like you just want some adjustable rockers. There's nothing wrong with that. Go buy em. And then make sure they get installed correctly.
Everybody likes an improvement over stock equipment.
I know I do.
 
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