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Not long ago I went to easyasone2three's house to help with his new toy. A "survivor"72 BB. Nice car. Engine was a little tired, and we spent a few weekends cleaning/blasting/painting/etc. I rebuilt the dizzy for him. Lars rebuilt his quadrajet. He removed the manifold for blasting/painting. We also pulled the pan to change rear seal and installed a "1 piece" oil pan gasket.
I told him about my days in high school working at a service station. We serviced a fleet of BB trucks for a supply company. I remebered I replaced timing chains and exhaust manifolds like a clock.
SO, while the manifold was off, we peeked thru the front china wall, and this is what we found.








You see this is one of the Generals "Not so bright" ideas. These aluminum cam sprockets were coated with nylon to quiet the valve train.
This car has less than 51,000 original miles.
So, any of you guys with original BB engines with 50,000 miles or more. Take note.
Needless to say, we replaced it with a Comp Cams True double roller set.(Made by Cloyes). Now, with the rebuilt carb, fresh timing chain, and the timing set-up per Lars papers, this car SCREAMS.
 

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Yea... aluminum... not so good. We're talking about a torque monster big block that's shreding tires and the competition. Why would you use aluminum? Don't get it. I've seen better teeth in a West Virginia trailer park. Oh wait... no I haven't.
 

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BTW, if your still not convinced, think about WHERE all those little pieces of nylon go and what they do,if your clueless...they tend to block or restrict the oil flow into the oil pump pick-up and get ground up and forced into the oil passages by the pump gears


The CLOYES true roller style is vastly superior




how come its 180 degs out of phase?
I get this question all the time, well here’s something I see lots of guys don’t understand, ONCE YOUVE INSTALLED A CAM WITH THE TIMEING MARKS YOU MUST ROTATE THE CRANK 360 DEGRESS BEFORE DROPPING IN THE DISTRIBUTOR, while its true that if the, timing marks are positioned so the crank is at 12 o,clock and the cam gear is at 6 o,clock that the cam lobes will be in the position that fires #6 cylinder that HAS NO EFFECT AT ALL (on finding TDC,) for aligning the degree wheel with TDC,or THE timing tab pointer, for degreeing in the cam, the piston passes thru TDC TWICE in every firing cycle once on the firing/power stroke and once on the exhaust stroke, the cam rotates at exactly 1/2 the speed of the crank so to make it easy to line up the marks they install it with the marks at the closest point 6/12 for easy indexing, rotate the engine 360 degrees to the #1 TDC power stroke and the crank gear will still be at 12 oclock 12/12 but the cam will be at 12 o,clock also, rotate another 360 degrees and your back where you started. its simply easier to index the cam at the point where the index marks align closely. look at how the cam lobes themselves open the valves when the cam is just installed the #1 cylinder valves are slightly open and the #6 are closed per "Lunati" ‘’YES YOU ARE RIGHT - WHEN CRANK IS AT TWELVE AND CAM IS AT SIX THEN #6 CYL IS FIRING AFTER YOU LINE UP YOUR MARKS AND INSTALL GEAR THEN ROTATE YOUR CRANK ONE REVOLUTION AND THEN DROP THE DIST. IN - AT THAT POINT
 

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Yes, but if you do THAT Grumpyvette, you alter the firing order....it becomes 65437218......

AND I have never heard a timing chain of any type in my whole life...I have even tried with stethascope, hose, screwdriver....etc....them thing make no noise .....so I fail to see how Detroit in general, across the board with all makers used those damn plastic gears....GM, Ford, Chrysler.....pull em outta every type V8 ever built....frm Chebby to Caddy, to 318's. to all Fords....

it's a money making thing for the stealerships....I fail to see any other reason....

CASE CLOSED....
 

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"Yes, but if you do THAT Grumpyvette, you alter the firing order....it becomes 65437218......"

YOUR going to just CONFUSE the GULABLE newer members with posts like that

THE FIRING ORDER DOESN,T CHANGE GUYS HES JOKING

use of the dots, as index points will work most of the time in theory, youll be close to correct, if you want things dead on correct you need to take the time to degree it in, the difference can be 5-20hp depending on how lucky you get with tolerances
take the time to read thru the whole thread and sub linked info
its well worth the effort

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=90&p=114#p114
 

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Holy cow guys! Why make this so difficult? Just put the chain in with the dots lined up-- Crank at 12:00 and Cam at 6:00. Then drop the disty in so it's pointing at #6 cylinder, or where ever you want the #6 plug wire to be and GO. Or rotate the crank 1 (ONE) turn and drop it in at #1.

And yes, the stock timing chains in ALL GM's are krap. Either gears (if you can stand the noise and DO NOT have a knock sensor) or a double row roller chain.

:cheers:
 

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Some gear drives offer the option of "extra loud whine". That's for me!!! Maybe I'll even have some cheese with that whine!!! HA! :laughing:
 

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I have a new set of those for sale, too, fit a SBC factory roller block.....found out I could not use them with knock sensor....

which I find out I may well have been able to do....but it's been ten years now...
 

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nah, I buy in the US, jsut add tax & shipping :) That drive is on a running engine, I have another one brand new in a dispay LOL I have some other old race parts in several displays, mostly old mech FI stuff like drives, covers pumps...that sort of stuff. I'm a sucker for old mech FI junk :D
 
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