|
Re: TOTAL ADVANCE-WHAT RPM
[Re: cudaboone]
#724784
06/15/10 09:42 AM
06/15/10 09:42 AM
|
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
|
Actually you just want to choose springs that will keep you just under the pinging point @WOT on your hottest/driest day going up thru the gears at whatever RPM that lets it max out at which may be in the ~1500-2500 range.
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: cudaboone]
#724786
06/15/10 03:30 PM
06/15/10 03:30 PM
|
Joined: Jan 2003
Posts: 5,444
Indiana
YO7_A66
master
|
master
Joined: Jan 2003
Posts: 5,444
Indiana
|
""How does the different size springs effect the advance?""
The heavier the spring(s) tension are, the longer it takes for the advance plates to extend which delays the rpm of the timing.
Light springs = early full timing advance
Heavy springs = later full timing advance
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: cudaboone]
#724788
06/15/10 07:31 PM
06/15/10 07:31 PM
|
Joined: Apr 2007
Posts: 1,261
ILL
mark7171
pro stock
|
pro stock
Joined: Apr 2007
Posts: 1,261
ILL
|
The curve can be set for the timing to follow the torque curve before it peaks. If your engine is built , it wants more fuel, then needs more time to burn the fuel. 36-38 total offers the best advantage for the flame to achieve volumetric efficiency. Cruising vacuum alterations , hot no crank starts , fuel, and detonation keep you from locking it out at 36.
You will find a run-of-the-mill 268 cam may like 18-20 initial with a 850-1000 rpm idle. Have it all it by 2200, which should be when the converter starts locking. try a 14 deg locking plate to limit the extra advance from the curve. After 2200rpm you will stay under 34 deg. away from detonation.
If you can not hot start at 20 initial mechnical, use a MSD starter retard device. If you overheat at 20, fortify your cooling system.
Run a vacuum advance if you drive it on the roads. Adjust it for cruising. You can run ported or full vacuum, but set it with the FULL vac advance at idle in mind. At WOT the vacuum gets down to zero, then it is out of the way.
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: mark7171]
#724789
06/16/10 07:58 AM
06/16/10 07:58 AM
|
Joined: Apr 2010
Posts: 236
Maryland
cudaboone
OP
enthusiast
|
OP
enthusiast
Joined: Apr 2010
Posts: 236
Maryland
|
How do you know all this stuff?
It is a 528 hemi. 10.75 Compression
comp roller cam installed @110.0. valve timing @ .050 Int: open open 14 close 54. exh open 54 close 14
gross valve lift .604 intake .585 exhaust.
tappet lift 286 286
1050 holley dominator.
5 speed trans.
Indy cylinder heads.
What will cause detonation? Too much advance or not enough advance?
Non vacuum MSD distributor.
If anyone has a 528 similar, what is your setting at 850 RPM? What is your total advance?
Last edited by cudaboone; 06/18/10 01:50 PM.
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: cudaboone]
#724793
06/18/10 03:42 PM
06/18/10 03:42 PM
|
Joined: Apr 2007
Posts: 1,261
ILL
mark7171
pro stock
|
pro stock
Joined: Apr 2007
Posts: 1,261
ILL
|
Quote:
How do you know all this stuff?
It is a 528 hemi. 10.75 Compression
comp roller cam installed @110.0. valve timing @ .050 Int: open open 14 close 54. exh open 54 close 14
gross valve lift .604 intake .585 exhaust.
tappet lift 286 286
1050 holley dominator.
5 speed trans.
Indy cylinder heads.
What will cause detonation? Too much advance or not enough advance?
Non vacuum MSD distributor.
If anyone has a 528 similar, what is your setting at 850 RPM? What is your total advance?
Get a MSD limiter bushing from FBO(4secondsflat) cause your gonna need a short curve. limit it to 10 degrees more plus an initial of 24. A 14deg limiter bushing with 22 inital could work well too.
Then there is possiblility you may need a MSD starter retard device. Then you can hot start , comming back from the piggly wiggly. Instead of crudely turning the distributor back by hand for the hot start.
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: mark7171]
#724794
06/18/10 05:36 PM
06/18/10 05:36 PM
|
Joined: Apr 2010
Posts: 236
Maryland
cudaboone
OP
enthusiast
|
OP
enthusiast
Joined: Apr 2010
Posts: 236
Maryland
|
I just set the idle timing 850RPM at about 22 BTDC and it seems to idle nicely and steady. I like the idea of the 14 degree limiter. How does this thing work and where to get it. I will surely have it by midweek.
Seems to start good when hot withing a few minutes, but after sitting a while and still pretty hot, she can be a little [Edited by Moparts - Family Friendly Site - Keep it clean] to start. That was at 18 BTDC, maybe at 22 it will start better hot!!
Right now i have to two heaviest springs?
Last edited by cudaboone; 06/18/10 05:41 PM.
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: cudaboone]
#724795
06/18/10 05:46 PM
06/18/10 05:46 PM
|
Joined: Apr 2007
Posts: 1,261
ILL
mark7171
pro stock
|
pro stock
Joined: Apr 2007
Posts: 1,261
ILL
|
Have you taken off the distributor cap , or switched advance springs on the weights? Have you ever built a engine yourself? MSD has a bushing on a peg , controls the total advance amount by how much the weights fly out , adjusts with bushing thickness. 4secondsflat.com sells the part. Don, is a nice guy to seek addvice. Some limiter bushins should come with the MSD unit.  AT 22 initail it will start harder hot. At that level you need a MSD starter retard device. This retards the ignition 10-25 degrees while cranking. So 22 initial will start hot like it was 12. It will crank hot like the spark plugs are out. This saves your starter and flywheel big time. http://www.summitracing.com/parts/MSD-8984/One concept you should be familiar with . An engine requires different timming at WOT than at cruise. A vacuum advance usually conrols additional advance past the total mechanical to relax the beast at road speed.
Last edited by mark7171; 06/18/10 07:19 PM.
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: mark7171]
#724796
06/18/10 06:06 PM
06/18/10 06:06 PM
|
Joined: Apr 2010
Posts: 236
Maryland
cudaboone
OP
enthusiast
|
OP
enthusiast
Joined: Apr 2010
Posts: 236
Maryland
|
I have learned that on this site. However, my distributor does not have vaccum pot and the engine does not have any way to get vacuum. Neither The 1050 dominator nor the dominator intake have any vacuum connectors?
I found the FOB site and will get the 10 and 14 degree advance things. Me taking my distributor apart should be a made for TV event.
I have never built and enging and have never taken a dist apart, but i am pretty mechanically minded except for electrical.
If i try to go to 12 BTDC, she will not even run.
Last edited by cudaboone; 06/18/10 06:12 PM.
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: cudaboone]
#724797
06/18/10 06:30 PM
06/18/10 06:30 PM
|
Joined: Apr 2007
Posts: 1,261
ILL
mark7171
pro stock
|
pro stock
Joined: Apr 2007
Posts: 1,261
ILL
|
Everybody needs a place to start , right? Why not a 528 hemi DREAMCAR. It will start fine with the MSD device. the retard only happens during crank. once lit the carb should choke and high idle out of the crank. Hot the high idle wont be an issue it seems to be above 800rpm.  They sell 1" carb spacers with ports for pvc and brake booster.
Last edited by mark7171; 06/18/10 07:22 PM.
|
|
|
Re: TOTAL ADVANCE-WHAT RPM
[Re: mark7171]
#724802
06/30/10 03:52 PM
06/30/10 03:52 PM
|
Joined: Apr 2010
Posts: 236
Maryland
cudaboone
OP
enthusiast
|
OP
enthusiast
Joined: Apr 2010
Posts: 236
Maryland
|
Quote:
Have you taken off the distributor cap , or switched advance springs on the weights? Have you ever built a engine yourself?
MSD has a bushing on a peg , controls the total advance amount by how much the weights fly out , adjusts with bushing thickness. 4secondsflat.com sells the part. Don, is a nice guy to seek addvice. Some limiter bushins should come with the MSD unit.
AT 22 initail it will start harder hot. At that level you need a MSD starter retard device. This retards the ignition 10-25 degrees while cranking. So 22 initial will start hot like it was 12. It will crank hot like the spark plugs are out. This saves your starter and flywheel big time.
http://www.summitracing.com/parts/MSD-8984/
One concept you should be familiar with . An engine requires different timming at WOT than at cruise. A vacuum advance usually conrols additional advance past the total mechanical to relax the beast at road speed.
Got the parts from FOB. Believe it or not, i took the dist out, took it aprt and installed the 10 deg bushing. Had to do a little filing, it so big. Don at FOB told me what to do. Haven't had a helper yet to try and set it at 32 deg total. Did set idle (about 900 RPM) at 22 and it seems to like it there.
Will that retard box work with my summit dig inig box (street & strip)?
|
|
|
|
|
