Follow-up to Cam & Valvetrain Dilemma... Got Engine Started!

[fine69]

Hey Guys and Gals...

Just a quick update... After a full-day at a swim meet yesterday morning and afternoon, I managed to get my "re-rebuilt" engine started late in the afternoon (now CS1062R Sealed Power cam, Performer manifold installed)! I used a spare Edelbrock 600 cfm, instead of the Edelbrock 650 cfm AVS. I am seriously considering a Q-jet instead of the Edelbrock.

To break-in the new cam, I ran it for approx 25 minutes at 1,900 - 2,400 RPMs... then tuned it as follows: dwell: 30 degrees; timing: 8 degrees BTDC @ approx 900 RPMs. It sounded pretty good-- nice and strong without any pops! I did run hot at 240 degrees (the left side ceramic coated headers actually got discolored), and the radiator "puked" toward the end of the period.

We were on our way out the door to go to Antietam Battlefield, MD for the fireworks and music show -- Independence Day celebration... so I ran out of time, and I couldn't actually drive her.

It did diesel some when I shut her off, so hopefully it will start again today!

Ralph

Threads related to this ongoing problem (Thanks everyone for all the advice):
http://corvetteactioncenter.com/forums/showthread.php?t=82048
http://corvetteactioncenter.com/forums/showthread.php?t=82479
http://corvetteactioncenter.com/forums/showthread.php?t=82310
http://corvetteactioncenter.com/forums/showthread.php?t=81122
http://corvetteactioncenter.com/forums/showthread.php?t=81969
http://corvetteactioncenter.com/forums/showthread.php?t=81122

 

[Jack]

Late Saturday afternoon in MD? ... guessing it was at least 90* outside during breakin? Maybe you needed to feed the front of car with a good fan? Also sounds like the timing wasn't right for the breakin ... maybe too high ... maybe vac can pulling in too much timing ... dunno? Was it 240* with the cap on & tight? Did it puke w/ the cap on & tight?

Before you started, Did you check the rockers & plates for good valve tip alignment? Did you check again after breakin?

 

[fine69]

Late Saturday afternoon in MD? ... guessing it was at least 90* outside during breakin? Maybe you needed to feed the front of car with a good fan? Also sounds like the timing wasn't right for the breakin ... maybe too high ... maybe vac can pulling in too much timing ... dunno? Was it 240* with the cap on & tight? Did it puke w/ the cap on & tight?

Before you started, Did you check the rockers & plates for good valve tip alignment? Did you check again after breakin?

Yeah, it was a hot one... I found out the following day that I needed more coolant... I had put in two gallons, but needed another gallon (runs much "cooler" now... relatively speaking of course).

All rockers and plates were straight-on before starting... I re-checked them today and they're still straight.

She's running much better than before, but sluggish upon take-off in first gear, and riding at low RPMs.

I printed out the articles John Z wrote ("Timing and Vacuum Advance 101" and "Mapping Your Advance Curve"), and plan to go step by step to get this old gal running correctly again.

 

[Jack]

Ralph:
JohnZ's timing info is good ... recommend you get familiar with it. Another gent named Lars Grimsrud also published good timing info & vac can ID-specs. Both gents' info quite helpful & reliable.

Check this before setting up timing: ... VERIFY that your timing mark is truly at TDC when piston#1 is truly at TDC. Sometimes timing TAB is mislocated and/or wrong damper with wrong timing mark and/or damper's rubber-outer ring slips ... either/all will show false TDC and any setting from that baseline will be false.

Have you a vacuum gage? ... what is manifold vacuum at idle? Can't say without some readings ... but possible your vac can is pulling in too much advance timing too soon causing sluggish at lower speeds ... if so, a different vcan may solve that as MOST vcans are not adjustable.