My Coil story...its entertaining....

[V8bait]

Justin where do you source your mosfets? I've been using ones from digikey that are what I believe are equivalent but I'd like a better mosfet if available

You can PM if you would like..

Side note.. Got my turbos back from pure and still collecting parts. Hope to get started tuning in a couple months (nice cool fall weather aka boost season lol)

Fairchild 14N30 is 14 amps and 300 volts which is higher than the msd80 came with https://www.digikey.com/product-detail/en/fairchild-semiconductor/FDB14N30TM/FDB14N30TMCT-ND/1566830

There's others you can use that are better but the one in OP's car was rated lower. It would have worked but I have no idea how well.

 

[Bmwfixerguy1]

Fairchild 14N30 is 14 amps and 300 volts which is higher than the msd80 came with https://www.digikey.com/product-detail/en/fairchild-semiconductor/FDB14N30TM/FDB14N30TMCT-ND/1566830

There's others you can use that are better but the one in OP's car was rated lower. It would have worked but I have no idea how well.

Thanks a bunch I can't find my old invoice of which ones I've used in the past. Order up a few sets though

 

[Erichale77]

Which are the best mosfets to get for the msd80?

 

[Bmwfixerguy1]

Which are the best mosfets to get for the msd80?

LOL this is what we literally just discussed and he even posted a link.. Read the last few post you even get a bonus link for reading

 

[V8bait]

I think he means are there better one than linked, answer is yes, but unnecessary. You can almost think of these as a fuse for feedback. You need enough, so that in case you get a voltage spike from the piezo it doesn't fry the chip... But at the same time you don't want to go with a 30A MOSFET or 500V MOSFET that will let too much backwards into the DME (they are kinda like a diode with some reverse allowance). 240 was factory I think, which wasn't quite enough. If you want a better one I'd say maybe one rated at like 20 amps and 320-350 volts would be high enough, with better thermal properties than the 14N30. But they go from like $1.50 to like $6 each for that and it's kinda wasted I feel.

 

[The Convert]

I think he means are there better one than linked, answer is yes, but unnecessary. You can almost think of these as a fuse for feedback. You need enough, so that in case you get a voltage spike from the piezo it doesn't fry the chip... But at the same time you don't want to go with a 30A MOSFET or 500V MOSFET that will let too much backwards into the DME (they are kinda like a diode with some reverse allowance). 240 was factory I think, which wasn't quite enough. If you want a better one I'd say maybe one rated at like 20 amps and 320-350 volts would be high enough, with better thermal properties than the 14N30. But they go from like $1.50 to like $6 each for that and it's kinda wasted I feel.

What do you think about the ones from Tyco?

 

[Erichale77]

Thank you Justin. That's all i needed to know.

 

[antiochasylum]

You went from worn out coils to brand new ones that produce much higher spark potential. Your old mosfets were probably just fine with old, weak coils. It's pretty much a given that your mismatched mosfets were the issue.

Incorrect. I had brand new Bosch coils with less that 2500 miles on them.

Thanks.

It was clear there was issues with my car. There was too many variables as Justin said. I'm not an endless bank. Money after money towards it does not leave a good taste in my mouth. Like sour milk, so I took them off. Because it got so bad just NORMAL driving would misfire. I went back to what I know worked. And it did. I've started numerous times they probably would have worked just fine. But i didn't want to re install them.

 

[Bmwfixerguy1]

Thank you Justin. That's all i needed to know.

Wasn't replying in a dooshy way.. I was giggling when I wrote it I thought it was super ironic that it's exactly what we were talking about at the moment

 

[V8bait]

What do you think about the ones from Tyco?

Which one? https://www.digikey.com/product-det...emiconductor/FDB20N50F/FDB20N50FCT-ND/4806461 looked pretty good but there are a few things I'd wanna check first, it's a fancy MOSFET for sure though. Almost twice the heat dissipation of the 14N30 which is already good. It's also more than twice the price lol.

Incorrect. I had brand new Bosch coils with less that 2500 miles on them.

Fosho, not stirring anything, I don't think the coils killed the MOSFETs either, it's just typical msd80 bullshit you drop a feather it drops a MOSFET. I think Convert was just getting at the fact they are sensitive, any change/mod really can upset those things lol, especially things related to misfires (like coils). Who knows maybe that extra couple amps was the straw, your car was undiagnosable. I was at DME or wiring harness lol.

 

[Erichale77]

If he would've said WHICH ones were better than the ones you were inquiring about, i wouldn't of asked.

 

[Bmwfixerguy1]

I think he means are there better one than linked, answer is yes, but unnecessary. You can almost think of these as a fuse for feedback. You need enough, so that in case you get a voltage spike from the piezo it doesn't fry the chip... But at the same time you don't want to go with a 30A MOSFET or 500V MOSFET that will let too much backwards into the DME (they are kinda like a diode with some reverse allowance). 240 was factory I think, which wasn't quite enough. If you want a better one I'd say maybe one rated at like 20 amps and 320-350 volts would be high enough, with better thermal properties than the 14N30. But they go from like $1.50 to like $6 each for that and it's kinda wasted I feel.

Isn't it funny just how much you need to modify on our/modern cars.. I never remembered there being this many week links.. We use to buy a boost controller, some shiny pipes and a big intercooler and still had some cash left over for a turbo timer lmao.. Yup I said turbo timer haha..

 

[Bmwfixerguy1]

If he would've said WHICH ones were better than the ones you were inquiring about, i wouldn't of asked.

I agree I'm diverting all attention on me appearing as a forum dick onto it being justins fault.. Goodnight guys lol

 

[V8bait]

I agree I'm diverting all attention on me appearing as a forum dick onto it being justins fault.. Goodnight guys lol

It probably was that's why I spent my afternoon soldering

I kinda go out of the way for the Texas peep!

 

[Bmwfixerguy1]

It probably was that's why I spent my afternoon soldering

I kinda go out of the way for the Texas peep!

Everything is bigger in Texas.. Including the hearts of the vendors

 

[The Convert]

Which one? https://www.digikey.com/product-det...emiconductor/FDB20N50F/FDB20N50FCT-ND/4806461 looked pretty good but there are a few things I'd wanna check first, it's a fancy MOSFET for sure though. Almost twice the heat dissipation of the 14N30 which is already good. It's also more than twice the price lol.



Fosho, not stirring anything, I don't think the coils killed the MOSFETs either, it's just typical msd80 bullshit you drop a feather it drops a MOSFET. I think Convert was just getting at the fact they are sensitive, any change/mod really can upset those things lol, especially things related to misfires (like coils). Who knows maybe that extra couple amps was the straw, your car was undiagnosable. I was at DME or wiring harness lol.

Actually. Looks like these are the ones I picked up a year or two back to have on hand. Might have to grab a new set instead.

 

[doublespaces]

Hi, I'm a 2009.

 

[antiochasylum]

Hi, I'm a 2009.

That .018 gap.

 

[08_335i]

Let me make one thing clear. In over 3 years I did not have a single misfire on 18psi. So to say I had a "ton" of ignition issues is way off point. Once I installed the PR set, a mosfet blew. And after that it was an onslaught of issues. Replacing with a different part number or what ever we will never know the exact reason.

Don't say an onslaught of issues when that was not the case.

Thanks.

You replaced multiple items on your car that were old, out dated, and needed upgraded or had failed. You had many more issues then just one. I think in all fairness you should swap the PR kit back on ( if you still have it ) and see if the problem persists.

 

[antiochasylum]

You replaced multiple items on your car that were old, out dated, and needed upgraded or had failed. You had many more issues then just one. I think in all fairness you should swap the PR kit back on ( if you still have it ) and see if the problem persists.

No. Is PR going to pay me labor to do it? I have removed these things easily 7-8 times in this process. No no no.

Are you going to come do it? Then no. Car runs great now on BL coils.