View Full Version : anyone run locked out timing on a BBC or SBC
Sean Cooke
04-25-2015, 08:47 AM
After reading various sources on timing, I'm wondering what if any input you guys might have on eliminating the distributor mechanical advance. Thus running the timing completely locked at let's say 37* degrees. Love to hear any pros & cons on running this setup on a road course and or autocross. Thanks in advance for any input.112019
68Cuda440
04-25-2015, 12:18 PM
For racing only this is fine. Ideally, when running mechanical advance you want it "all in" by about 3000 rpm. In a racing situation you do not spend much time below 3000 rpm, so not much difference. From the other side of the coin, if you are running 37 total including mechanical, then what would you gain? Since you spend most of the time above 3000, you are running full advance most of the time anyway. Car would be easier to start if it is not locked out.
Sean Cooke
04-25-2015, 12:49 PM
For racing only this is fine. Ideally, when running mechanical advance you want it "all in" by about 3000 rpm. In a racing situation you do not spend much time below 3000 rpm, so not much difference. From the other side of the coin, if you are running 37 total including mechanical, then what would you gain? Since you spend most of the time above 3000, you are running full advance most of the time anyway. Car would be easier to start if it is not locked out.
Thanks 68cuda440 for the response, I'm running a digital 6plus Msd box which allows me a setting for 20* degree start retard. this will hold the advance until 800 rpm and kick in again under 500 if neccasry. I think this puts a ease on starting and kick back from compression. I recently had a spring in the mechanical advance fail over the weekend. Now I'm interested in eliminating the advance.112022
68Cuda440
04-25-2015, 07:14 PM
I'm running a digital 6plus Msd box which allows me a setting for 20* degree start retard. this will hold the advance until 800 rpm and kick in again under 500 if neccasry. I think this puts a ease on starting and kick back from compression. I recently had a spring in the mechanical advance fail over the weekend. Now I'm interested in eliminating the advance.
That should work fine. The cat's meow is the MSD 6530, with that box you run your distributor locked out and program the curve with your laptop. There is even a way to get it to do vacuum advance. Follow along on this thread if you are interested in how that works: http://www.lateral-g.net/forums/showthread.php4?t=48612
Sean Cooke
04-25-2015, 10:10 PM
That should work fine. The cat's meow is the MSD 6530, with that box you run your distributor locked out and program the curve with your laptop. There is even a way to get it to do vacuum advance. Follow along on this thread if you are interested in how that works: http://www.lateral-g.net/forums/showthread.php4?t=48612
That Def looks cool, but I'm shooting for simple. Lol I just don't see the purpose of the advance. I have 3000-3200 stall converter, my car won't really be moving until the timing fully advances Anyways.112031
sam 74
04-28-2015, 09:17 AM
i run locked out timming at 38* on the street and track, i use a start retard when its hot out, other than that no issues and my big block has 11 to 1 compression, i have a CSR high torque mini starter to help out a bit also.
Sean Cooke
05-05-2015, 08:25 PM
I'm going the locked out route, supposed to really clean up throttle response & just one less moving part. My timing has been doing something very unusual Lately
SSLance
05-06-2015, 03:10 AM
I initially thought the MSD 6530 was a bit complicated as it was all new to me, but once I got it all in place, it's the cat's meow really. I have my advance all in by 2800 RPM but my engine spends a lot of time in lower RPMs on the street and coming out of the corners on autoX courses where it doesn't need as much.
What was really cool was when I had the car on the chassis dyno and we decided to pull a degree of timing out, just punched a few buttons on the laptop and BOOM...timing changed.
Sean Cooke
05-06-2015, 12:18 PM
I initially thought the MSD 6530 was a bit complicated as it was all new to me, but once I got it all in place, it's the cat's meow really. I have my advance all in by 2800 RPM but my engine spends a lot of time in lower RPMs on the street and coming out of the corners on autoX courses where it doesn't need as much.
What was really cool was when I had the car on the chassis dyno and we decided to pull a degree of timing out, just punched a few buttons on the laptop and BOOM...timing changed.
I'm going to look into that, this is the 1st I'm seeing of this new 6al that's programmable.
Will it work in conjuction with the pro billet dist?
MonzaRacer
06-22-2015, 05:33 PM
Had a few guys use CCC locked hei's the ones from the elctronc carb engines. I used to have list of hei modules that advance or retard the timing. So far can't find it.
But the distributors fit, work well and are very reliable. And its easy if you have right module to get a start retard. Had one guy with no extra cash want to take kids racing. His old neighbor had garage filled with old car mags, old car parts, the didn't have much cash but old man willed all his stuff and garage and land to them.
So they built up ol Duece Nova he had, 13.5 -1 roller cammed 327, solid can, 4 SPD factory 4.10 gears.
On 14" slicks ran 6.80 in 1/8th.
It ran low 7's till the found article using retard on distributor module. That is where I got info.
One module you ground, one you run power to, one gives retard other gives advance.
My issue is unless your pushing 300-400 HP or NOS or lots of psi, I would NOT run locked dist. on street.
One, hard to start, two, locked for controlled timing by box, three, no benefit but properly dialed in distributor with proper curve, vac advance etc will make car more drivable and get better mileage.
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