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Help!!! Do I need to break in new heads

  • Thread starter Thread starter Luke Wallace
  • Start date Start date Feb 23, 2012
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Luke Wallace

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I just installed new Edlebrock performer heads. Thinking nothing of it, I opened it up immediately. From the first start up, it seemed like there was a bit of friction getting out of first. After I opened it up, it seemed like the friction had gotten worse. I googled, and the general concensus was that you don't need to break in new heads, so I wondering if the friction is just me.

Any thoughts?
 

Noobz347

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#2
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Question:

What does, 'friction coming out of first' have to do with a head swap? Maybe I'm not understanding what you're saying.
 
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Luke Wallace

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If I start out slowly in first, it feels like there's a lot of friction on the motor. Definitely not smooth like it used be.
 

CarMichael Angelo

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#4
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Noobz347 said:
Question:

What does, 'friction coming out of first' have to do with a head swap? Maybe I'm not understanding what you're saying.
Click to expand...

You Know!! He means
Friction.
 

tannerc91gt

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#5
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Luke Wallace said:
If I start out slowly in first, it feels like there's a lot of friction on the motor. Definitely not smooth like it used be.
Click to expand...
as in a load on the motor? or...sorry this is hard to follow.
 
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Luke Wallace

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Is that the mayham guy in your pic... funniest commerical ever... any ways, I dunno. I suppose you could call it load. The power is totally there after about 3000 rpms, but it feels off at low speeds. Friction might not be the right description. What about clunky? It's hard to describe. In any case, do you have to break in new heads?
 

tannerc91gt

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Luke Wallace said:
The power is totally there after about 3000 rpms, but it feels off at low speeds.
Click to expand...
sounds like a stock-ish 302 to me but you could have a miss, or a lot of other things. Id start the usual process of pulling codes and go from there.

and yeah, its the insurance commercial guy
 
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Luke Wallace

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Cool. Thanks.
 
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Luke Wallace

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Also, it's a stock 88 302
 

CarMichael Angelo

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Luke Wallace said:
Is that the mayham guy in your pic... funniest commerical ever... any ways, I dunno. I suppose you could call it load. The power is totally there after about 3000 rpms, but it feels off at low speeds. Friction might not be the right description. What about clunky? It's hard to describe. In any case, do you have to break in new heads?
Click to expand...
No.
The only parts of a motor that require breaking in, are the piston rings. Being that you only replaced the heads, then we'll assume that the bottom half is already broken in. I am troubled that you took on a head swap,w/ a NBD attitude, but you are having difficulty describing what the problem is, or that you don't know cylinder heads do not require a break-in period.
 
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Luke Wallace

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I'm definitely new to this, but I did hire a professional mechanic to do the install. It's just that something seems off. The power's there on the top end, but it's rough starting out. It sounds like everything's fine, and I'm just being paranoid. Thanks for the input, everyone!
 

88LX5.Oh

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You said it was an '88, so I must ask, is this a speed density car or mass air? Because, I know with my car (also '88), after I did the HCI swap, it was a complete dog until over 3000 RPM(i've now converted to MAF). I am not sure if just a head swap is enough to throw the speed density system off enough to make it act like this, though. Does it run rich at idle? Is there any idle surge?
 
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Luke Wallace

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Actually, I converted to maf. I installed the ford motor sports conversion kit. It was a while ago that I installed it. I haven't experienced idle surge after the conversion.
 
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Luke Wallace

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Can the ecu handle a mod of this caliber? Might I need a tune?
 

88LX5.Oh

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Well since you've converted, pay no attention to my previous comment haha.
 

Noobz347

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#16
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I'll take a wild stab here and you tell us which parts are wrong:

You put a set of heads on the car. They are larger than stock.
You're using either the stock exhaust manifolds or shorty headers going into an otherwise stock exhaust system
You converted to mass air using an OEM meter
You're using the OEM throttle body
You're using the OEM cam
You're using the OEM intake
The bottom end is also bone stock and has some pretty good miles on it

Correct the errors in the above list.
 
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Luke Wallace

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I've got BBKs shorty headers going into a larger than stock, but can't rember by how much, exhaust
Using OEM meter
Using 65 mm Edlebrock throttle body
Using OEM cam
Using Edlebrock Performer RPM II intake
Bottom end is bone stock, but with only 60k on it.
 

Noobz347

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#18
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You're not feeling a whole lot of action below 3000 RPM because your cam and meter are having difficulty filling those heads with air. Your exhaust scavenging probably leaves something to be desired as well.

What heads and more importantly, what size are the heads? What size are the combustion chambers?
 

LilBerx

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#19
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From what I've heard, cars are dogs if you add H/C/I without converting to MAF.
 

foxbodymike87

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i say you need a bigger cam
 
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