318 won't rev past 3000 rpm

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Wow, I really appreciate all the suggestions so far guys. Here's the list as I see it so far:

Cap
Rotor
Wires
Spark Plugs
Check weights in dist for proper movement.
Diaphragm for secondary throttle blades (test/replace)
Weak valve springs
Control box (switch for orange?)
Filter sock in fuel tank

I have to head back up to Ottawa for school for the next week, so I won't be able to report back until next weekend.
 
One more thought on my part is to make sure ignition box is well grounded.
 
Cudafever said:
If it revs to the same rpm in neutral as it done going down the road. I would be thinking valve spring are weak.

plunged exh could cause a simile reaction.Does the exh really hiss (no exh tone just fast sounding air rushing though?
Click to expand...

I knew a guy who had a chevy with the same problem. Turned out the cam went flat. We put a new cam in. Problem fixed.
 
rtgambit said:
Wow, I really appreciate all the suggestions so far guys. Here's the list as I see it so far:

Cap
Rotor
Wires
Spark Plugs
Check weights in dist for proper movement.
Diaphragm for secondary throttle blades (test/replace)
Weak valve springs
Control box (switch for orange?)
Filter sock in fuel tank

I have to head back up to Ottawa for school for the next week, so I won't be able to report back until next weekend.
Click to expand...

With the control box, it doesn't have to be an upgrade-it's up to you how much money you want to spend just to slave one in, but if you're working with an OEM unit, upgrading surely can't hurt.

the filter sock in the tank is also very possible; my car sat in Houston virtually untouched for the better part of 8 years, and the top of the tank was completely rotted away...the fuel left in the tank from before it was stored resembled something out of the primordial era and clogged the fuel line all the way up to the pump.

Weak valve springs are definitely a possibility, but 3,000 is pretty damn low for valve float even if it was sitting for a few years...even my turd didn't drop off that fast.

All in all, I'm more inclined to believe the ignition or plugged exhaust to be a culprit...JMO
 
Dart Gone Fishing said:
I knew a guy who had a chevy with the same problem. Turned out the cam went flat. We put a new cam in. Problem fixed.
Click to expand...

If the can had a flat lobe, you hear it every time it reconnected to the lifter. An out of the ordinary tapping. Unless of course ALL the lobes are flat.
 
WoodenNickle said:
If the can had a flat lobe, you hear it every time it reconnected to the lifter. An out of the ordinary tapping. Unless of course ALL the lobes are flat.
Click to expand...

...in which case, it would likely have some serious rocker noise.
 
Have you checked the voltage at the + side of coil? Lower than 7V, may result in a very weak ignition at higher RPM.
 
Dont miss that it could be a bad distributor pickup.

If it actually does pull good up to 3000 and no more, I would have to agree with exhaust limited also.
Especially if it acts exactly the same in neutral.
(By valves or by plugged)
 
X-streamly advanced cam timing? had the same issue with my old lebaron when 1st owner put timing belt in 2 teeth advanced it had all sorts of low end power then fell on face before it would reach the shift point. somthen else to check out man.
 
The final verdict?

Ignition box. Instant change in the engine - it would happily rev to 5k with no problems after a new one was installed.

Just wanted to tip my hat to all that helped out with suggestions. Greatly appreciated.

Next up: get the timing/carb dialed in (slight bog from idle).
 
Could be any of 20 things.

Ignition Box..........Simple........

I had listed.....

* Fuel Tank inlet tube 'clogged'
* Bad Fuel Pump
* Clogged Fuel Lines
* Timing Chain
* Valve Stuck Open
* Distributor Shaft worn
* Coil defect {cracked or corroded}
* Muffler pipe collapsed. Had that happen to me on a 1971 Chevrolet Malibu 307. The car wouldn't rev over 2500 RPM's.
 
Great that you found it. As for an engine with a Holley sitting for years - the first thing I'd do is get a good rebuild kit for it and go through it. They don't age well in most cases and open element air cleaners allow a lot of crud into the air bleeds and passages. Even if it runs well I do this every few years as normal maintenance.
 
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