msd or thunderbolt 4
 

I have a 502 650 hp. should I go msd or thunderbold 4? msd has a big box when the thunderbolt looks eaiser what are your thoughts

Re: msd or thunderbolt 4
 

TB IV dist with a Crane Box.

Re: msd or thunderbolt 4
 

I've used the Tbolt on two performance engines so far with no problems. 1st was a 406 small block with 10:1 with solid lifter cam. 2nd was current 540 at about 550 hp. I would spend $$ on other items first.

I would be interested to hear who is using Tbolt on big HP engines, and what HP?

Re: msd or thunderbolt 4
 

I second this. The Crane box with the Thunderbolt distributor gives a lot of adjustability for $$$. There is no doubt the Thuderbolt is a great ignition system but it is limited by its set advance modules. The Crane is wide open on what you want to do.

Re: msd or thunderbolt 4
 

I have 625 hp NA 540s (9.3 c/r)with T-Bolts. Work fine and top of the chart for reliablity :cool:
MSD :p
T-Bolt distributor and Crane boxes are good too but I don't feel the advance curve is that critical on a boat. Biggest importance is you overall timing and let the idle timing fall where it may.

Re: msd or thunderbolt 4
 

548 cid; 620+ hp @ 5500 rpm. Very happy with my T-bolt IV using 20* adv. module. --- Jer

Re: msd or thunderbolt 4
 

Totally impessed with TB IV on hp marine engines.
Totally impressed with Crane HI-6M on marine engines.
Not to keen with the MSD system on marine engines.

The TBIV distributor does not have the corrosion problems that plague the MSD's.

Marine engine's - for the most part - don't turn mega rpm and/or create super high cylinder psi that over burdens a mild powered ignition system. A way too lean or way too rich condition will run better with a CD ignition, but, this is marine and we have things tuned correctly right ? If we have an application that idles a ton and tends to foul plugs and we have tried everything to tune this out, then a CD box will help big time. Just skip buying a corrosion prone distributor, keep the stock one, and add a much more reliable (then MSD) cd box from Crane.

Re: msd or thunderbolt 4
 

I was told to use the T-Bolt system and that the NASCAR Guys run multiple systems for a reason.

Re: msd or thunderbolt 4
 

and I've only seem MSD's in NASCAR. So if they are so bad, and Crane is so good, why are the guys who can have what they want using MSD?

Re: msd or thunderbolt 4
 

TB4 with MSD. Benefit is, that if the MSD box breaks, you switch a couple of wires and keep going. TB4 does not need the box to run, where the MSD Dist (except the RTR) is dead with no box.

Re: msd or thunderbolt 4
 

I don't know squat about the msd set up. But have recently come across a couple of threads mentioning that they develop rust. No 1st hand experience, just what I've read recently.

I have run a TBIV in my ZZ502/502 for 4 seasons and have had 0 problems with it.

Re: msd or thunderbolt 4
 

Those blue boxes in the windshield on Sunday are Crane. The Crane system is very popular with the Nascar boys.. . .of course this comes from an "oil pan salesman".

Re: msd or thunderbolt 4
 

I run an MSD billet distributor and an MSD crank trigger system hooked up to a Crane Hi-6M ignition box. A crank trigger system may not be totaly necessary, but it's one of the best systems out there and it works very well in a marine environment---at least it has for me. Haven't had a problem with a Crane ignition box yet either---they are over 5 years old. :D

Re: msd or thunderbolt 4
 

All the top Nextel teams use MSD ignitions
http://www.msdignition.com/news2006.html

Re: msd or thunderbolt 4
 

So why do they run 2 boxes ?

Re: msd or thunderbolt 4
 

the msd distributers have a severe corrosion issue with the trigger wheel becoming rusted then knocking out the 6m box.you can keep cleaning the rust but the boxes get expensive for the customers,and this is in a fresh water environment.just my professional opinion.

Re: msd or thunderbolt 4
 

NASCAR teams need to finish to win. Just like any other part on a race car, an electronic piece can fail. If an MSD box were to fail, they would not be able to finish. They are allowed to run two of them, and they do as cheap insurance. Any backup system that a NASCAR team can run, they do. If they were allowed to run a second engine, they would do that also. :D

There are many other choices in ignition systems. The fact that most of the top 25 teams in Nextel Cup use MSD should speak for itself.

Re: msd or thunderbolt 4
 

Understood. But why do these boxes fail ? We use the marine box & seems to fail when needed the most. Seems they only last so long. I've got mine mounted on rubber bushing's & thought vibration was a factor. I have a 2 engine aplication and would like to run a spare box. Could I run 1 spare switched to 2 engines ? Would it be possible to get a schematic on that ?

Re: msd or thunderbolt 4
 

Still coming up to speed on marine stuff, but Fasteddy is right. MSD's are run all over the place in motorsports because they've been around forever, and once apon a time, they provided the best spark you could get in an ignition system. But now there are better, more reliable modules out there. However, anywhere they run one, they run two. They're VERY old technology electronically speaking, and are not very reliable.

Although a crank triggered, multi-spark, distributorless, CD ignition is certainly going to give a better, more controlable spark under all conditions, for my money, on a boat, simpler is better. Sounds like you guys have good luck with the TB's. Unless I had plug fouling, idle, or high rpm issues, I'd stick with the "old reliable" any day. The more electronics you put into the boat, the more you have to go wrong (and this comes from a long time FI guy)

Re: msd or thunderbolt 4
 

There are several ways to wire up spare boxes. This link shows the easiest using an MSD switch
http://www.msdignition.com/pdf/6%20series/pdf7.pdf

It would probably be cheaper and easier to set up your spare box so that it is a direct plugin to the wiring on the engine. (as you have marine boxes, they already have the watertite plugs) Then, if you had an issue with the box, you could just switch the wires, and continue on.

How many hours/time are you running the box before you have a failure issue?

Re: msd or thunderbolt 4
 

good thread i always thought msd was the only way to go i guess if that eas the case the super cat motors would have them on them............. i never put two and two toghether..........i just bought a new billet msd dist because my old msd got rusty on the inside..............

Re: msd or thunderbolt 4
 

I'm suprised not many people use the $149 GM external coil HEI (efi one) distributor along with the Crane Box. Just bypass the distributor's module and wire up Crane Box + coil. Cheaper, many more features, and one hell of a reliable system. USCG approved to boot.

My 02.

Re: msd or thunderbolt 4
 

How many hours/time are you running the box before you have a failure issue?

I've got as long as 3 years and as little as the following season.
FRom the looks on the schematic I would need a spare box per engine ?

Can you offer the OSO gang an awesome discount ?

How do you hook up a MSD box to a TB4 (plastic module)...
Tried this last night in a hurry but no avail...MSD tech says the 6A or whatever isn´t compatible with the Hall-type TB4 is using?
HEI instead or suggestions.. not keen on a MSD dist. because if it the 6Afails you´re in trouble.
Did get the MSD for help in starting and idling mainly as it´s a mildly modified 454 with hard starting as TB4 is known to be...maybe I was just too tired think clear.

800 ++HP so far, TB 4- 14 Deg. V-6 module moving to over 900 HP in a couple of weeks. 500CI Blower 8 pds boost. No problems so far with the TB-4 except that I had to plug in my spare module this year at the river. I was down for three minutes. So far I love TB-4. Carry a spare module....

Howabout starting the TB4 sure doesn´t light right up as an MSD does.
I´ve tried a 11:1 true (measured) comp SBC with a seriously stout cam starting in 10 degree temps and with MSD it hit on like from under a palm tree right away.
Without it no chance to even light up at those freezing temps.
I do like TB4 but I like the engines to fire right away, Always.

Also looked into another set of Merc Distributor (TB4) today and it was rusted inside too.

I will somehow get the bugger working, maybe a pertronix is the way to go.

OK
A little tip. MSD has what they call a noise filter Summit racing has them and so do I on my FULL MSD system. The filter also prevents voltage spikes the kill the control boxes. I wouldn't run an MSD without this wired in.

MSD Problems
 

MSD + Salt water = Junk and it breaks parts
Engines (yes two) started kicking back like timing too far advanced. Broke two starters before timing light establishes no advance cure, just total advance. I call MSD technical support and they tell me it can not happen as a loss of springs would result in retard (I think the person on the help line was retarded).
Attached is a photograph of the one remaining spring.
If you use an MSD, inspect under the cap and rotor for rust frequently. My $.02.

that broken spring has nothing to do from marine use, my top sportsman camaro suffered the same spring breakage last year, car just would not idle....ckecked timing and was all over the place. I run a mallory unilite in my boat, works very well(so far) love the advance adjustment feature...Rob

Why not HEI....... I am running the HEI...... Easy hook up..... dead reliable timing to 7000....... and if something does go wrong any autoparts store has the cap and rotor.

I am pleased that MSD is following this thread. I used the Thunderbolt IV system in racing and pleasure flawlessly for 15 years. Racing was 1hr+ at 5000-6500+RPM....never a issue and used the same (2) Merc distributors with the same (2) Merc V-6boxes for the entire time. I changed the caps and rotors annually and the pick-up in the distributors about every 2-4 years.
We switched to a MSD mechanical system in 2002.:mad:
IMO, the MSD mechanical distributor is a PITA and shouldn't be marketed for a marine application. We could only get the boat to idle when we finally locked-out the advance feature, but that is not how it is sold. I was convinced we could fix it, but was wrong.
MSD, your marine customers have a high probability of struggling with the idle in an out of gear with the MSD Marine System...the timing keeps moving along with the RPM.
I'll be positive, why not market an MSD marine ignition system with an electronic advance instead a converted automotive based design? MSD could offer one electronic advance box (CG approved) with choices for multiple advance curves and a rev limiter and move into 1st place.
I will be your first customer for two of the new systems and sell my existing MSD in the OSO Swap Shop to someone who hasn't read this thread:drink:
Ben