454 BB running rough

[454 blazer]

Hey,guys need help:
My big block is popping on tick over and deceleration , it smokes a white cloud on start up.Also its very hard to warm up and sounds like its not firing on all cylinders until warm, a few things ive noticed are:

A small hole on the intake manifold (Aluminium)
I noticed that 2 spark plug boots are melted through were they were close to the headers i repaired them with high temp clycone, will it last ?
I had the carb cleaned recently.
Also very high pitched whistle is coming from around the intake aswell.

An help from you legends would be great !

Cheers Simon

 

[Cornfield creations]

Cam good? 454's tend to eat lobes off of the cam. Buddy had a similar problem, cam was smooth on the cylinder 8 lobes

 

[454 blazer]

Cam good? 454's tend to eat lobes off of the cam. Buddy had a similar problem, cam was smooth on the cylinder 8 lobes

So thats what sounds like ? Dam it ! do you think any of the other reasons i mentioned could possibly be the culprit ?
Thanks for replying.

 

[diesel4me]

I'd plug up the hole in your intake (vacuum leak,is whats making the whistle and will make it idle poorly or stall)--and replace the bad plug wires..THEN you can see if it has another problem,these things must be corrected first..you can use J-B Putty if its a hole in the intake,if its a port thats threaded ,use a proper sized plug to seal it off...if its a hose nipple ,use a vacuum cap or peice of hose with a bolt in it to block it off...

 

[thatK30guy]

All the answers/solutions have been suggested.

For the plug wire/header problem, get some kevlar thermal boots to protect the wire boot by the headers. They will slow down the burn-thru if you can't get them completely off or away from the header tube. You may need to look into different degree angle plug wires at the plug end. I've found most straight boots for BBC's burn too much on the headers and you need a 45 degree boot instead to clear them. 90 degree won't work either as I tried them, too.

 

[82355]

Didn't you have a flat cam a couple of years ago?

Martin

 

[454 blazer]

Didn't you have a flat cam a couple of years ago?

Martin

Well remembered Martin ! At that time i had small oval heads on with adjustable rockers i then did a cam and head change to the 502 rectangle port with none adjustable rockers so im kinda hoping that its not the same thingIm going to do as suggested and replace plugs and wires get a carb kit and plug the hole in the intake and go from there.

Thanks to all who answered !

Cheers Simon