ignition modules ???
02-12-2009, 08:22 PM
#1
ignition modules ???
Hello All,
I was running a thunderbolt 1V module with these numbers on it 7K22A V8-22 . I was going to replace it with a crane box but the box is no good. The engine is a gen6 502 500 hp. My question is which is a better way to go leave this module in or replace it with a new crane box. I look a the crane box and the mercruiser module, boy there is a big difference in size betweeen the two, I now it has a couple different curves to choose from and a rev limiter but why is the mercruiser module so much smaller. Peace
I was running a thunderbolt 1V module with these numbers on it 7K22A V8-22 . I was going to replace it with a crane box but the box is no good. The engine is a gen6 502 500 hp. My question is which is a better way to go leave this module in or replace it with a new crane box. I look a the crane box and the mercruiser module, boy there is a big difference in size betweeen the two, I now it has a couple different curves to choose from and a rev limiter but why is the mercruiser module so much smaller. Peace
02-13-2009, 08:59 AM
#2
No expert here, but I do run a Crane box on my 557ci engine. In a nut shell, the box gives you 5 or 6 choices for when full timing is in. I'm sure one of the smarter guys here will chime in and give you a better explanation.
Overall the Tbolt IV very solid system. There aren't many complaints about the Tbolt failing, or not performing as it should. You won't gain much, if anything, by going with the Crane box. As long as you're in the 500 hp range, I'd stay with the stock Merc set up. When I had the ZZ502/502 in my boat I ran a Tbolt IV for 4 seasons without a glitch.
There are a few different Tbolt modules to choose from. I believe their main function is to dictate when the engine comes to full advance. Also, the Tbolt V modules limit engine RPMs to around 4700. The Tbolt IV modules don't incorporate a rev limiter.
Again, one of the guru's will be able to expound on this. fyi ... To buy a module new is pricey. But there are a bunch of used ones out there.
Overall the Tbolt IV very solid system. There aren't many complaints about the Tbolt failing, or not performing as it should. You won't gain much, if anything, by going with the Crane box. As long as you're in the 500 hp range, I'd stay with the stock Merc set up. When I had the ZZ502/502 in my boat I ran a Tbolt IV for 4 seasons without a glitch.
There are a few different Tbolt modules to choose from. I believe their main function is to dictate when the engine comes to full advance. Also, the Tbolt V modules limit engine RPMs to around 4700. The Tbolt IV modules don't incorporate a rev limiter.
Again, one of the guru's will be able to expound on this. fyi ... To buy a module new is pricey. But there are a bunch of used ones out there.
02-13-2009, 12:23 PM
#3
Charter Member # 55
Charter Member
The Crane box is more for giving a better spark. It gives a multiple spark discharge. The benefit of the Crane is that it has several timing curves built in.
Your TB IV module will probably work fine. Here is a chart. I'm not sure which one is the 22A and which is the regular 22 on the chart. A V8-HP would be better.
Your TB IV module will probably work fine. Here is a chart. I'm not sure which one is the 22A and which is the regular 22 on the chart. A V8-HP would be better.
