548 CI BBC Advice

General engine tech -- Drag Racing to Circle Track

Moderator: Team

CharlieB53
Pro
Pro
Posts: 223
Joined: Fri Nov 22, 2013 2:44 pm
Location: Wright City, Missouri

Re: 548 CI BBC Advice

Post by CharlieB53 »

It is interesting to note that the 'smaller' cam can produce more torque in the usable street RPM range while more cam can produce more HP at higher RPM.

Learning how to drive either one on the street and keep tires connected may be difficult, but certainly put a lasting grin on your face.
TBART1970
Member
Member
Posts: 71
Joined: Wed Feb 08, 2017 9:16 pm
Location:

Re: 548 CI BBC Advice

Post by TBART1970 »

BK8K0014.JPG
Cut open oil filter and found metal. Adjusted the valves, no problem found, decided to stick my scope in to look at the cam gear and noticed this lobe.
Sent pics to Bullet cams, I can't win.
IMG_20171114_185611549 (2).jpg
old cam 600 miles hydraulics 52 miles solids

Have not pulled apart yet, any suggestions what to look for?
You do not have the required permissions to view the files attached to this post.
prairiehotrodder
Guru
Guru
Posts: 1602
Joined: Sat Dec 24, 2011 10:02 am
Location: melfort saskatchewan Canada

Re: 548 CI BBC Advice

Post by prairiehotrodder »

are those pictures both the same cam? The top one looks worse. The top picture looks like my lunati cam that i bought used and was in at least 3 different motors. My Straub cam i bought new and used for 3 seasons and came out looking nearly as good as the day i put it in. I'm not an expert but with the deeper groove on one side i'd say the lifter wheel must not be sitting square on the cam. Has your block had the lifter bores bushed ? Has your block ever been over heated?
Brian
The Word of God is quick and powerfull
www.therocketshop.blogspot.com
TBART1970
Member
Member
Posts: 71
Joined: Wed Feb 08, 2017 9:16 pm
Location:

Re: 548 CI BBC Advice

Post by TBART1970 »

No overheat. No lifter bushings. bowtie block.
New cam then old cam.
prairiehotrodder
Guru
Guru
Posts: 1602
Joined: Sat Dec 24, 2011 10:02 am
Location: melfort saskatchewan Canada

Re: 548 CI BBC Advice

Post by prairiehotrodder »

is that the only lobe that looks bad? Is it a billet cam?
The Word of God is quick and powerfull
www.therocketshop.blogspot.com
TBART1970
Member
Member
Posts: 71
Joined: Wed Feb 08, 2017 9:16 pm
Location:

Re: 548 CI BBC Advice

Post by TBART1970 »

Billet cam, not sure how many look that way, looked in with my scope.
TBART1970
Member
Member
Posts: 71
Joined: Wed Feb 08, 2017 9:16 pm
Location:

Re: 548 CI BBC Advice

Post by TBART1970 »

No suggestions?
Newold1
Guru
Guru
Posts: 1963
Joined: Fri Apr 08, 2016 9:50 am
Location:

Re: 548 CI BBC Advice

Post by Newold1 »

Based on the pic with the pencil pointing at the wear on the flank of the lobe, there is a definite problem.

That cam is not a billet in my opinion looking at the areas next to the lobe !!

Send these pics to Mike at CamKing and he will tell you exactly what your issues and fixes should be made.

Let him spec, and make your camshaft and follow his instructions on valve train match and I suspect your problems will be over.

Stop rowing your boat uphill against the currents, go with the flow! JMHO
The Older I Get, The Dumber I Get :wink:
racear2865
Guru
Guru
Posts: 1595
Joined: Mon Sep 21, 2009 11:58 pm
Location: tenn

Re: 548 CI BBC Advice

Post by racear2865 »

My opinion---Cam is not a Billet probably a SADI. Roller either locked up or skidding.
reed
TBART1970
Member
Member
Posts: 71
Joined: Wed Feb 08, 2017 9:16 pm
Location:

Re: 548 CI BBC Advice

Post by TBART1970 »

Pencil is on old, cam not billet. New cam that is still in the engine is a billet solid roller.
Kbails
Member
Member
Posts: 120
Joined: Sun Apr 05, 2015 6:53 pm
Location:

Re: 548 CI BBC Advice

Post by Kbails »

I would pull the intake . yank the lifters and take a better look befor you run it much more. could be a soft lobe? or a failing lifter possibly. i would autopsy asap.
Long Island, NY
Post Reply