Does anybody use this box. I understand the way it works, but how does your initial timing come into play. How do you set your intial timing? Also how much retard? My motor is a 470 588hp will shift at 6000. Any help is could help. Thanks Rick
Rick, Do you have a locked out distributor, or is your mechanical advance operative? The box offers a 20* crank retard. If your timing is locked out at 34*, when you crank the engine, timing would be reduced to 14* below 1000 RPM . Above 1000 RPM, the timing would advance back to 34* by 3000 RPM. If the distributor uses a mechanical advance (not locked out), you cut the gray loop to bypass the crank retard. The high speed retard can be activated by a simple switch manually, or, if you would like to trigger it automatically at a certain RPM, you'll need to purchase an MSD RPM activated switch (#8950) The 8950 has two options, one wire closes to ground at the specified RPM, the other opens a ground. You plug an RPM pill, or use a module selector to select the trigger RPM. I have the MSD Digital 6 Box, it includes a high speed retard. I ran into trouble by setting the activation RPM too low at 4400 RPM. That is right where the RPM falls to at my 2-3 shift, and the engine did not like it at all. The only way I realized it was when I recorded my runs from inside the car. You could actually hear the engine lay down for a second, then pick back up. I had much better success by setting the activation RPM at 5000. For some reason, my aluminum heads love 39* of timing. The car ET's it's best with that timing, but JW advised me that the engine would not like that much timing above 5000 RPM, so I set my retard at 4* and pulled that much above 5000 RPM. It worked well for me at Cecil County this past October. You can actually listen to my runs in the BB Timing thread in the Race Forum http://www.v8buick.com/showthread.php?t=140064 Post #23
Larry How do you set your initial timing if the timing retard is messing with it? Or if the RPM is high enough to to all full advance through the box? I must be missing something it can't be that difficult. Thanks Rick
The 20* retard is a crank retard. It is meant to ease the load on the starter in the case of a locked out distributor (no mechanical advance). You shouldn't use it if you have a functioning mechanical advance. It only functions below 1000 RPM, when you are cranking the engine. The high RPM retard is a separate function. That is to retard the timing at higher RPM's. The Stinger S-4 did that, but it did it progressively, not in one shot. The high speed retard is also useful for nitrous and boosted applications. What is your initial timing now?
Larry This motor was built by AMP, I am not sure what the timing is for sure without looking at the paper work. When I installed the motor in the car with the timing box it didn't like where the dist was at. Thats why I was wondering about the initial timing in conjunction with the box. Thanks Rick
Rick, The reason it didn't like it was because the crank retard would drop 20* of timing. If your initial timing was say, 14*, that would mean when you cranked the engine, the ignition timing would be 6* retarded (ATDC). The engine won't want to start at that timing. You can't just change your initial timing because that will affect your total timing. Why did you buy the box? What was it you were you hoping to do? As I said before, if you want to use the crank retard feature, then lock out the timing. If the distributor is an MSD, this is easy to do, but it requires you remove the distributor. Once you lock the distributor, you set the timing to the total you want to run. Say, 34* Then the box will retard the timing to 14* while cranking. This assures less chance of a hot motor not wanting to crank with 34* of timing, and no problem with it kicking back and breaking starter motors. Once the engine starts, the 20* of timing is added back in above 1000 RPM. I don't see why you need this box.
Larry It was in the car when I bought it from Jeff Hart. It was kind of a plug and play thing. I figured if it would work I would use it. Thanks Rick
Forget it Rick. You need a locked out distributor to use the crank retard. You can play with the high speed retard if you like, but it requires buying a few other things to make it work.
Larry I believe everything is there, just need to lock out the dist. Is there any advantage in using high end retard? The motor is only going to 6000. Thanks Rick
The old Stinger S-4 distributors and boxes progressively retarded timing throughout the RPM range. They were worth a tenth or so if I remember. The Stinger box would retard the timing 1 1/2-2* per 1000 RPM, so you could run 38* or more timing and it would retard back to 34* through the traps. You can't do that but the box you have is capable of pulling timing in one step. I have done this with my MSD Digital 6 box. It seems to work well. This past October, I ran 39* of timing and pulled 5* out above 5000 RPM. I equaled my time from the prior year, and I was using a 2" taller tire. I still have to do more testing. Will it help you, maybe. No way to know without trying it.
Im gonna have to say i like the thing, but it doesnt seem to be too popular because alot of people dont understand how it works. EDIT: After reading through, i noticed you already own this. If you are set on keeping it, you need to learn the sweet points of the timing on YOUR engine. To use this box, or the 8981, you need to know EXACTLY what timing your engine likes, to be able to get the best out of it.... Instead of the 8980 i would recommend the 8981. I was going to get this thing for my small block chev, but i found a buick now, so plans have changed slightly... :3gears: Beforehand, you MUST lock out your distributor to use this box. To use my SBC as an example though, it pulled the hardest between 2000-5000 rpm at 36* total timing. However, past 5000rpm, it fell on its face, i may as well have been in neutral. (1/8 mile of about 79mph, 1/4 @ 93mph) At 33-34* total timing, i had the most horsepower between 4000-6200rpm, however it wasnt nearly as torquey as the 36*. (1/8 mile of about 76mph, 1/4 at 97mph). In either case, i had a hell of a time starting the car with a locked out distributor. The MSD box, tells you to lock your distributor at the MOST advance possible. Then it retards the timing 20* for regular operation (ie: below 2000rpm) and another 10* for start up. Between 2000-5000rpm, it moves the advace back to MAX, then in the last 1000 rpm or so, it will retard it 2-4 degrees to give you max horsepower. In a nutshell, a big cammed car (that would otherwise be very very lopey on the street), can start and idle like a mild V8, be mannered in city driving, have MAX torque, and MAX hp because of this nifty little box. Sounds appealing to me The MSD 8980 has preset points, and comes programmed. The MSD 8981 is programmable to the timing presets you choose.
I would get in touch with the builder, and see what he recommends for timing. OR you could do it the fun way and try it out yourself. You have to know EXACTLY what your engine likes to get the most out of the box. Use this graph to understand what youre trying to accomplish. (Page 3). http://static.summitracing.com/global/images/instructions/msd-8981_frm29232.pdf
Azeem I got that info, I just couldn't get it in my head on the intitial timing. This dist must not be locked. Thanks Rick
You must lock out your distributor to the max timing your engine will handle. ie: Get rid of the springs and counter weights under the rotor if they havent been removed already, and some how lock the advance mechanism in place (FULLY ADVANCED). Alot of people use zip-ties, but i would advise against it. The plastic can become brittle over time, and if it fails, it can be interesting trying to tame the car at those revs.... (if found out the hard way). This is what i used. I think its some sort of a lever for a house window, or maybe the base for a ceiling lamp. It aint goin anywhere.... Once its locked out at that timing, say 34*, then you control the other points using the 3 potentiometers on the box. To use my sbc as an example again; The stock engine likes; Initial = 10* Advance rate determined by springs (starting at 1200 rpm and all in by 2000rpm lets say) Total = 24* My current setup with a 284H cam likes; to start = 14* to idle = 24* to run at max torque = 36* <-----Locked out at this timing to run at max hp above 5000rpm = 34* <-----2* retard module for the box. So i would lock out my distributor at 36*. Then i would play with the potentiometers to give me 24* for idle to 2000rpm by telling it, that i want to "retard" the timing 12* from 36*. 36* - 12* = 24* Then i would set the start retard an additional 10*. Then i would install the 2" retard chip. So the Max advance your engine can handle, is a reference really, and everything else is adjusted FROM THAT TIMING. So the INITIAL timing, is controlled by the box, and you adjust it using one of the potentiometers. Refer to the instructions for more clarification.
Azeem If you look at fig #14 on page 9, that is part of my set up. My RPM is set by a adjustable unit. Thanks Rick
I see, So your system is set up for EVEN more fine tuning. You can not only control the high speed retard, but control WHERE/WHEN it comes on. You got some tinkering to do (if its not setup right). I think you can have alot of fun with this setup.
Azeem I think every thing is there just need to get it running then go play:beers2: Thanks for all your help. Rick
