[68cougar29]

Maybe I made a mistake asking Comp Cams about my advanced timing.
I told them about my power brake (hard pedal) I have a stock 302
2 bbl carb/Automatic Transmission that only had 13½-14" vacuum at
10-12 degrees BTC Not sure what cam I have because the receipt
is wrong (31-218-3 no such number) I guess it's a 31-218-2
Store that built it is out of business (1998 was built)

I mention that I had bumped the timing to 17degrees road tested
and up to 21degrees (no pinging)to get 16" vacuum and better performance.

They said 21 degrees would damage my engine plus my problem is the
power brakes or balancer has slipped.

After thinking it over I set the timing to 14 degrees rather be safe than sorry


They also said 13-14 is plenty of vacuum for "good brakes"?
Mine at 13-14 has a hard pedal and hard to stop. So I added a Crane Reserve
System Brakes are fine now.
Engine was built,new exhaust,checked the vacuum with all hoses
disconnected,tried another Carburetor,Crankshaft Damper is like new,
Rebuilt Power Brake Booster. If I back off to 12 degrees BTC
68 will lose power on acceleration not idle as smooth as 21degrees.
He never did say what the timing should be.
We have had the 68 since 1983 and never had any problems until
rebuilding the 302 with a mild street cam.

 

[towcat]

Check all of your vacuum hoses for leaks, check around the base of the carb. if no leaks are found, advance the timing until the engine starts to ping on a pull, and then back off the timing a little until no ping and don't worry about what the timing marks say.

 

[68cougar29]

Check all of your vacuum hoses for leaks, check around the base of the carb. if no leaks are found, advance the timing until the engine starts to ping on a pull, and then back off the timing a little until no ping and don't worry about what the timing marks say.

I have disconnected all the hoses including the power brake, read 13½-14hg
Engine has less than 1000 miles on it. How would you check for leaks?
A propane tank with hose? I don't want to burn down the garage along w/68

 

[68cougar29]

What gets me is Comp cams says their 31-218-2 will not effect the vacuum
or power brakes,then turn around and tell me 13" is fine for power brakes!!

Not on my cougar, any one else with same problems after installing a cam
with power brakes?

 

[doctordesoto]

forget comp cams and listen to towcat---the initial timming is a referance---advance it until it pings or better yet until it balks when starting---back it off a coulpe and tune or jet from there--whoever rebuilt it must have screwed up on the timing marks or dampner
doctordesoto

 

[68cougar29]

forget comp cams and listen to towcat---the initial timming is a referance---advance it until it pings or better yet until it balks when starting---back it off a coulpe and tune or jet from there--whoever rebuilt it must have screwed up on the timing marks or dampner
doctordesoto

That puzzles me,how can you screw up on the timing marks or crankshaft damper?
Damper has a key way I think and the degree marks?
You mean the timing chain and sprocket?

 

[70B302Cat]

That puzzles me,how can you screw up on the timing marks or crankshaft damper?
Damper has a key way I think and the degree marks?
You mean the timing chain and sprocket?

The harmonic balancer is basically made up of 3 parts, the outer and inner metal rings and a rubber isolater between them. If the outer ring is not properly positioned during assembly, your marks will be off.

 

[68cougar29]

If you use an adjustable vacuume advance and different advance curve springs, you can really clean up idle emissions and the vacuume will increase as will the starting performance and throttle response.

I like that idea and I think I'll research as to how. Last guy told me harmonic balancer
could be the problem,makes sense and I thank him for that Info.