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I see it is missing some intake manifold bolts. Can you look down inside those holes and see threads? If so you maybe want to remove the intake manifold and install new gaskets and maybe a new intake bolt set.
 

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what else i have notice is that the engine gets warm within seconds..2 mins of running and you can't touch exhaust and the the rocker covers are warm.
I noticed you have a sharp kink in your bypass hose. Thats the hose going from the intake manifold to the top of water pump. If it is restricted it will cause it to heat up quick and overheat. If you can, try to straighten that hose or replace with an actual bypass hose. You have to trim them to fit and when you install it you want the water to flow from the intake to the pump with no restrictions.
 

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Oh also, the exhaust you have on there are Headers. They get screaming hot as soon as you start the engine. At night with no lights on they will be glowing red. Don't judge engine temp using these but if you have an infrared temperature sensor the headers are a good place to check for low output cylinders. Obviously if one of the tubes is cooler then the rest, that cylinder is not making as much power.
 

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I am pretty sure that is the wrong spark plug for that engine. I believe it should have a tapered seat and no gasket. I am not totally sure how it will effect the spark plugs heat sink ability but is can't be good. It also doesn't look crushed, but that may be how it will look when tightened against a tapered seat instead of a flat surface. This is the plug designed for that BBC. R45TS.jpg
 

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Discussion Starter #25
Iam connected to the full manifold on the carb.as per picture and manuals.. by the way I also got msd iiridium plugs and new msd leads for my engine brand new . Just to see if that helps.
 

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You need to figure out why the gauge is not reading vacuum. The engine has a vacuum, even a race engine will register a slight vacuum. Possibly the port isn't drilled all the way through. I would hook up to the rear of the carb on the power brake port for testing. And to the point up above with the spark plugs. Big block chevy's used both types of plugs so find the casting number on the heads and see what year heads they are or are they aftermarket.
 

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Discussion Starter #29
I am pretty sure that is the wrong spark plug for that engine. I believe it should have a tapered seat and no gasket. I am not totally sure how it will effect the spark plugs heat sink ability but is can't be good. It also doesn't look crushed, but that may be how it will look when tightened against a tapered seat instead of a flat surface. This is the plug designed for that BBC. View attachment 398351
I know !!:) been looking at plugs since I have the engine and the ones I had / have are not listed on anybody’s forum talking about 454 engines :)? But knowing that I have iron heads the original length 0750 could be right ? I mean how can I find out?
 

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398360

But that’s what’s on from factory ?? Did something break? Should I completely block it off ?
Yes... Remove the hose and "T" fitting that came from the factory and block off this carb port if it is not connected to anything.

But knowing that I have iron heads the original length .750 could be right ? I mean how can I find out?
If these are GM heads, remove one of the valve covers and look for a number that has been cast into the head (see example below).
398358

Once you have the casting number for the heads on your engine, be sure to post them. I'm sure someone here will point you in the right direction for the correct spark plug.

It is possible that you might be using the wrong spark plugs for your heads. This might explain why you're killing spark plugs after a very short use.
 

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Yes I agree with RifRaf but you might want to remove both valve covers to see if the casting match or are compatible. Post the casting numbers here. We should be able to tell you the plugs required for that head.
 

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Should be ACDELCO R45TS spark plugs R = Resistor, 4 = 14 mm (thread size), 5 = Heat range (5 is in the middle), TS = Tapered seat with Extended Tip. So an R43TS would be a colder version if you have issues with preignition when the weather gets hot. Gap should be .035". They don't have to be AC Delco plugs. DENSO 5029, AUTOLITE 26 or any brand you prefer.
On the vacuum issue are you sure the gasket or something under the carb is not blocking the port you are connected to? I mean the engine runs so it has to have vacuum or it wouldn't pull the fuel out of the carb. The plugs are black so for sure it is pulling the fuel out of the carb. If it didn't have vacuum you could put your hand over the top of the carb and it wouldn't try to suck it in. I can hear it has vacuum in the videos.
 

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Based on the information the OP provided...
The head casting number indicates that they were produced from 1966 thru 1970. From what I have read, GM began to produce the 454 big block engine in 1970. The block casting numbers reference to a 454 big block produced 1971 thru 1979 (or 1972 thru 1978... depending on the different info on the web). I am far from a Chevy big block expert, but it is possible that the heads on your engine may have been swapped from another big block.

GM also started to switch from the gasketed plugs to the tapered/conical plugs around 1970/1971. So to help confirm what type of spark plugs your engine should be using, you may need to remove a couple plugs and take a very close look at the plug seating area on the head.
*Is it flat?... or is there a taper/bevel into the threads?
*Can you tell how deep within the head the threaded portion for the spark plugs are (about 1/2" or 3/4").

If possible, can you take a close-up photo of the spark plug opening on the head and post it.

Example of a tapered/beveled spark plug port.
398382


Example of a gasket/flat spark plug port
398383


398385
 

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The cylinder heads will have a casting date also located under the valve cover. You can use that to distinguish when it was made or what engine they may have come on.
 

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its tapered
398387

It looks like Ed D was correct and you had the wrong spark plugs installed in your heads (photo shown above).
It's just a guess, but maybe the "no vacuum at idle" was caused by improper spark plugs not seating correctly within the head... causing a vacuum leak at the spark plug seats.

Suggest changing the the spark plugs that Ed D recommended and see if your vacuum level improves.
You may also want to address the other items that Ed. D mentioned in some of his previous posts (bypass hose, missing intake bolts?).
 
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