Lets talk distributers
 

I need 2 new ones... so MSD has a E-Curve distributor http://www.msdignition.com/Products/...stributor.aspx

Would be nice to set variable timing instead of locked out timing right?
This distributor eliminates the other MSD boxes.
My only concern is reliability.

Or send mine in to get rebuilt by MSD for $200

Or just buy 2 of these brand new units for $300

http://www.amazon.com/Mallory-85551M...pr_product_top


Any input is appreciated!

I bought the MSD E-curve distributor and hi vibration epoxy blaster coil, has a rev limit built in (adjustable) and a lot of settings available by turning two settings

Custom bushings in the MSD. The least amount of centrifugal advance msd offers is 18 Degrees. We all love the better idling of more initial timing esp with a big cammed blower engine. A custom 10 degree bushing, will allow for 20-24 degrees of initial, and you can bring the timing in when needed with the spring combinations. Rebuild the distributors you have. That one with the bad bearing and scored shaft for sure.

Good plan Wild Thunder!

The END

im with wild thunder,bying new would be a major blunder.rebuild what you have,leave them locked as supercharged engines like the advance even at idle and you can use the money you will save to buy yourself a couple oso t shirts.:lolhit:

Now they have rotary dial distributors? What's next touch tone tachs? Happy New Year. Randy

I tried the custom 10 degree bushing and went to a locked distributor. I also tried the MSD start retard box and threw it out. Locking the distributor was the best thing I did, great idle and incredible acceleration. I just make sure to get the motor turning before I bump the gas.

Id like to hear some of the pro engine builders thoughts on this. I myself have been running locked timing for a few seasons, they start fine and idle good. Its a very simple way to set things up, and works for me, but very old school.

My question, is with a boosted engine, in a heavy boat like icdedppl has, is the amount of timing at say 3000-3500rpm. With a full load of people and fuel, in choppy water, drives and tabs down a bit, he might be into boost at that low rpm. His engines at that rpm in a 30FT cat will probably be pulling a decent vacuum signal still. I notice most of mercurys older supercharged engines, like the 525sc, 600sc, 800sc, etc, all bring the max timing in late in the rpm band.

So for conversation purposes, lets say you dyno an engine. Lets say the engine likes 34 or 35* of timing. But, from a safety standpoint, you say, I am gonna set it at 30 or 32 degrees total, to prevent detonation. Lets say the fuel curve is right. At what point in the rpm band, would the engine be most likely to suffer from preignition? Back in my car days, I remember spark knock being more of a problem at low rpm, high load, than it is at high rpm high load. I can remember foot braking the car and you can hear it rattle itself if the timing was too far advanced. So, would it be better to pull a little timing from the lower rpm ranges, and bring the rest in when the engine starts to rev? And rather than pull max timing out to be safe, give it the timing it wants at wot, just don't bring it all in at a low rpm.

Some of these new ignition setups, like the programmable msd 6530 box, Daytona sensors I believe, Mallory maxfire, etc, can do some pretty intense stuff with the timing controls. You can really trick out a timing map using your pc or laptop. The question is, is it worth it. I don't know what guys like Eddie Young, Haxby, Chief Engines, Sterling, etc are doing as far as timing curves. I do find it hard to believe on the awesome engines they are building, that they are locking the distributor out and calling it a day.

What did you not like about the 10* bushing?

This is how Mercury does it...... none of their motors are ever just locked


http://33outlaw.zenfolio.com/img/s5/...02661519-4.jpg

Mercury Might know something that some others don't! maybe! "just sayin"

Heres an 800SC


http://33outlaw.zenfolio.com/img/s9/...86820522-4.jpg

Does merc lock the timing on the 1350?

Stock Mercury motors typically don't have big cams that bleed off cylinder pressure at low rpm. I have a pretty big cam and I need as much advance at idle to keep it running smooth. That's also why I can lock my distributor and not have a problem with pre-ignition. If you are running a blower with a smaller cam than you definitely don't want to lock the distributor, you will have to much cylinder pressure at low rpm and detonate.

I should also mention that the start retard devices that use rpm to switch timing can be very problematic. When you have a big cam and are trying to maneuver into a tight space and are switching from forward to reverse, your rpm can drop below the switch point. Trust me, it's not fun your already struggling to keep your big cam motor idling low to keep from annoying the neighbors and you suddenly loose 10 degrees or more of timing. I'm running 10:1 compression with a big cam and I don't have any problems starting hot or cold with a stock Mercury starter.

What are your cam specs? Lift and Duration at .050, with valve open and close #s, Are you supercharged running 10:1 Comp? Just tring to learn more about these things! Thanks in advance.

Here is a clean and right way to do it they will do custom curves and they are a Fully Electronic system.
http://performancedistributors.com/p...-distributors/

i doubt it,fuel&spark are all controled by the computer,not old school like us poor guys run.

we all have our opinions,i personally would not use the dui dist if they gave them to me for free.it is a glorified hei dist.

I don't know much about this conversation but I will say this...I bought 2 brand new msd distributers and after one season I took them apart and they both looked horrible all rusty and corroded. I put moister bags in the hatch and I don't even leave my boat in the water. Last year I switched over the the DUI and man I pulled them apart this month after a whole season and they looked like the day I bought them. Not one spot of rust or wear. Just like brand new! Some people say u loose hp with the DUI but on the water their is no way u can notice a difference. Maybe on the track when ur talking a fraction of a second. DUI makes a true marine dist.

I had my msd distributors rebuilt at msd a couple years ago, as they were rust buckets inside. When I got them back, they looked like new. I gave each distributor a coating of CRC Sp 400 corrosion inhibitor. It's not like wd40, it leaves a waxy film on the components. Anyhow, that was 3 years ago and they look very good still today.

Maybe You Should read the first post and then you would under stand what he is asking that is why I gave a link on a good Marine Distributor close to what he was looking at and not HIJACK his thread.

The cam in my 524 is a .623/.612 lift with a 242/252 @ .050" duration and a 112 LSA, I am running NA at 10:1. This is a carbureted motor so no IAC to help keep the idle up when Several comments have been made on the stator rusting in the MSD distributor. I soaked mine in rust remover and then soaked it in Gun Blue with a coat of Amsoil metal protector, It's been 4 years and it still looks the same as when I first did it.

The DUI isn't an option with a 1071 blower with HEI cap.

Also, I do not believe the DUI has a programmable advance curve via a laptop or pc. It uses centrifugal weights like a standard MSD distributor which the OP already has.

I have no experience with a DUI, and I am sure its a good distributor setup for the money. I still would prefer a digital capacitive discharge style ignition for a 850-900hp supercharged engine.

i prefer a mag for blower engines....

maybe you should read all the posts in this thread,you just might learn something,like i said DUI dist is not a good option for a supercharged engine and how in your mind is my post [hyjacking]the thread?

why a mag for a low boost pump gas engine?

DUI, and MSD also make small cap HEI distributors that work very well. The stock small cap GM units and coils have no problem on an 1100hp blower motor if everything else is set up correctly. There are different modules, which are easy to swap, with only two screws holding them down, and most have a very short electronic curve. Some have 4 or 5 degrees advance, some have 0. The module is less susceptible to RFI, and creates a very clean square wave signal which is great with EFI, or with any ignition box you want to use. Obviously, a crank trigger is better still, but everything has it's place.
Locked out timing on low compression blower motors works quite well if you don't have the ability to program a curve. Some of the higher end boxes will give you quite a bit of control, which for guy's like Mike, or Mild, who really like to dial their stuff in, can be an excellent tuning tool, and add some safety. You're basically running an engine management system without the fuel control portion. What you want is a 3d map that will allow timing vs load and rpm. As well, you want modifiers that will adjust timing vs inlet/manifold air temp, and knock. With these parameters you can really optimize your tune.
Running very low ignition timing at idle is an excellent way to combat reversion. Additionally, adding a bunch of timing in the high load lower rpm area where it goes into gear, can really help prevent stalling. You can add timing at low load cruise rpm to reduce EGT's and improve efficiency, and then pull it out at higher load, pull a bit near peak torque, and add a couple again at higher rpm. Etc.. You get the idea. There's many ways to do it, and sometimes the simple way is best. It's really up to the end user and his comfort level in tuning, and budget.

Alex, in regards to OP's engines. 540's, 10-71's, iron heads, no intercoolers, carbed. They are in a old 38 Cig. He likes to cruise with the family. Timing was currently locked at 32. Engines idle great, and once the carbs were dialed in, they ran good. My concern I brought up to him, is that I noticed while being a passenger, in choppy water with the drives tucked and tabs draggin a bit, at 3000-3500 he is in the boost. 1-3psi. And now he finally has some props that hook up, and load the engines quite well planing. His engines were tough to crank, even though I believe that is a boat wiring issue, as I have the same starters as him, locked timing, and a higher cranking psi on my engines.

My initial thoughts were to remove a little lead down low in the rpm band, and just bring it in later. Then I started looking at some of the capabilities of the newer ignition stuff, as far as programmability, and they have a lot to offer. While I too run locked timing, with good results, I am always open to an idea that their might be something better on the market. The 3D map is neat stuff

We are installing air temp gauges to monitor intake temps

Maybe you should read post #27 you might learn more sense you think you know every thing The right DUI will work just fine.

I love winter :food-smiley-007:

im just phuckin around mike,,i like the msd programable box's where you can ramp in timing where ever its needed and just run the locked out dist or even better the crank trigger is even more accurate..but most people have troubles phasing the distributor their first time using a crank trigger..