Ignition question

[lordhelmet]

Hey,

has anyone tried MSD's Off-road ignition box. The one that is supposed to provide multiple sparks for 20 degrees of crank rotation. The sales pitch makes it sound like a good thing, but I would like to hear from someone that has used one before I invest the money.

Any opinions or thoughts would be appreciated.

Here is a link if you are not sure what it is.

http://www.msdignition.com/ignition_8_6470.htm

Thanks in advance.

 

[4X4HIGH]

Hey,

has anyone tried MSD's Off-road ignition box. The one that is supposed to provide multiple sparks for 20 degrees of crank rotation. The sales pitch makes it sound like a good thing, but I would like to hear from someone that has used one before I invest the money.

Any opinions or thoughts would be appreciated.

Here is a link if you are not sure what it is.

http://www.msdignition.com/ignition_8_6470.htm

Thanks in advance.

All of the MSD boxs do that. The only difference between a regular box and the offroad box is the rubber isolation feet and the water tight seal on the offroad box. MSD = Multiple Spark Discharge.

 

[lordhelmet]

Perhaps a better question would be, Is this worth investing in?

 

[Mike D]

If you are going to install it on a TBI fuel injected vehicle, you will have to purchase an adapter harness that connects 4 small wires from the MSD box to the coil. Before I rebuilt the engine in my truck I installed the MSD 6A ( not as waterproof as the off road box ). It immediately improved both starting and overall engine performance. When I converted my 350 to TBI I purchased the harness adapter and MSD coil designed for the TBI setups. The MSD 6A has been used for 8 years with a carb on this truck and 6 months with TBI. I am and have been very pleased with the ruggedness of the MSD equipment. At the time they did not offer an offroad product. You might try EBAY For a used unit. Either it works or it don't. The MSD web sight will display how it should be wired. Thats my opinion and I am sticking to it!

 

[dyeager535]

IMO it's not.

At higher RPM's (in excess of 4500) HEI can start to drop off in performance. For anything other than that condition, I don't understand how multiple discharge can do anything. As far as I know, either you ignite the mixture or you don't...1 spark or two million, if it lights and burns, it lights and burns. You are still only igniting the mixture from one point, the plug.

Very little I've seen in actual dyno testing of the MSD setup, it makes sense since the magazines are usually the only ones with budgets that support extensive dyno testing, and who pays for tons of advertising? The *one* dyno test I saw showed no improvement over HEI. I believe that is the ignition article on my website.

On top of the additional cost, its something else to fail, that can cause troubleshooting headaches.

 

[4X4HIGH]

FWIW i have the MSD-6A box and also the coil and billet distributor. I did not notice any change after i installed those items.

However, a longer duration spark (multiple sparks) helps to get a more complete fuel burn. A more complete burn equates into a slight power increase and also a reduction in unburnt fuel which will help emissions testing. Like i said though it wasn't noticeable (to me).

 

[lordhelmet]

Thanks for the replys, I am still running a carb, wish it was injected. But after your responses perhaps I will just upgrade my coil and call it good. Truck runs good just always looking for a way to improve things.

Much appreciated.

 

[dyeager535]

Long tube headers/exhaust will be about your best bang for buck if you don't have them already.

 

[lordhelmet]

Thanks, already have the exhaust taken care of. Always looking for improvements though. I am thinking that I may just rebuild the HEI.

Much appreciatted.

 

[robert97dodge]

I got a question about hooking hook up a MSD ignition on a TBI 454. I have the MSD6 box I had on my old dodge and on the wiring diagram on the back of it, it says orange and another color goes to the coil. One is + and the other is -. How do you tell which is which on the coil? I have a MSD coil and MSD pro billet distributor. Should I just buy a harness to hook it up or is there a way to hook it up without a harness?