Tfi Modules... Any Power To Be Found

srtthis

the guy doing it does every local racers rear end
15 Year Member
Jul 3, 2009
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any one ever tested different TFI modules to see if one brand makes more power than another? life span for me doesnt mean anything if it makes more power (within reason). ive heard that the DEI and accell TFI modules have a bit more dwell time in them and make a few more HP.

if i have to replace them every year im ok with that
 
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I think you are really stretching for like .01 hp Skip the Doritos Tacos for lunch today and I think you might find some ET at the track... LMAO

In all honesty I can't see any one module making a significant difference over another.
 
I agree that you're probably scraping the bottom of the horsepower barrel with this but it'd be interesting to know. My question is, is increased dwell time really a good thing? I know I've come acrossed it in my tune and as well with the MS on the other car. I'd like to be corrected if I'm wrong but I'd think there can't be too many mS to play with in dwell time one way or the other? Too little and you're not fully charging, too much and you're not giving enough time to fully expend the charge?
 
I think you are really stretching for like .01 hp Skip the Doritos Tacos for lunch today and I think you might find some ET at the track... LMAO

In all honesty I can't see any one module making a significant difference over another.
Doritos taco= rocket fuel!
 
Only reason I'm even thinking about this.

Buddy of mine had a tfi go bad on him car would break up at 4500 like it had hit the Rev limiter. Put my distributor in the car with an off the shelf borg warner replacement tfi to confirm that was the issue. He picked up a new msd tfi and reported that the car felt stronger with the msd in his distributor over mine with the borg warner. So that got me thinking... is there anything to be gained here. Talked to an ex pure street racer and was told he ran an accell due to the extra dwell time...
 
Only reason I'm even thinking about this.

Buddy of mine had a tfi go bad on him car would break up at 4500 like it had hit the Rev limiter. Put my distributor in the car with an off the shelf borg warner replacement tfi to confirm that was the issue. He picked up a new msd tfi and reported that the car felt stronger with the msd in his distributor over mine with the borg warner. So that got me thinking... is there anything to be gained here. Talked to an ex pure street racer and was told he ran an accell due to the extra dwell time...

Only way to know for sure is to strap in on the dyno and see. Personally I'm leery of MSD and Accel products. I'd think a proper tune would compensate for any minimal lost hp regardless, no?
 
Only way to know for sure is to strap in on the dyno and see. Personally I'm leery of MSD and Accel products. I'd think a proper tune would compensate for any minimal lost hp regardless, no?
The problem with this is it is so hard to replicate one dyno pull to the next. There is always a variation in hp output one run to the next, even if it is less than 1% you could still have a 300rwhp car make 298, 300 and 297 all in back to back identical pulls making it hard to find an additional 1 or 2 hp.
 
Dwell is an electronic term that has to do with how long current is supplied to the coil primary windings. An increase in dwell increases the magnetic field inside the coil's primary windings. The coil only puts out a spark when the magnetic field collapses. The stronger the magnetic field when it collapses, the more energy is created in the coil's secondary windings and the more energy is in the spark.

This is only important if the spark energy is marginal to jump the spark plug gap. More energy than is required to jump the spark plug gap and ignite the fuel air charge doesn't accomplish anything but use more electrical energy, erode the spark plug electrodes and create heat. It also increases the tendency for spark to "leak" and find some path other than the spark plug electrodes to return to ground.

On top of that, creating a magnetic field takes time, as does the collapse of that magnetic field. Increase the dwell too much and the magnetic field doesn't have enough time to rebuild at high RPMS.

It's a fast, close electronic dance that everything must keep in time to prevent stepping on the toes of pretty girl you are dancing with...:)
 
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"Dwell is an electronic term that has to do with how long current is supplied to the coil primary windings. An increase in dwell increases the magnetic field inside the coil's primary windings. The coil only puts out a spark when the magnetic field collapses. The stronger the magnetic field when it collapses, the more energy is created in the coil's secondary windings and the more energy is in the spark.

This is only important if the spark energy is marginal to jump the spark plug gap. More energy than is required to jump the spark plug gap and ignite the fuel air charge doesn't accomplish anything but use more electrical energy and create heat.

On top of that, creating a magnetic field takes time, as does the collapse of that magnetic field. Increase the dwell too much and the magnetic field doesn't have enough time to rebuild at high RPMS."

I think this translates into "The brand of TFI if it is working properly doesn't make much difference"
 
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"Dwell is an electronic term that has to do with how long current is supplied to the coil primary windings. An increase in dwell increases the magnetic field inside the coil's primary windings. The coil only puts out a spark when the magnetic field collapses. The stronger the magnetic field when it collapses, the more energy is created in the coil's secondary windings and the more energy is in the spark.

This is only important if the spark energy is marginal to jump the spark plug gap. More energy than is required to jump the spark plug gap and ignite the fuel air charge doesn't accomplish anything but use more electrical energy and create heat.

On top of that, creating a magnetic field takes time, as does the collapse of that magnetic field. Increase the dwell too much and the magnetic field doesn't have enough time to rebuild at high RPMS."

I think this translates into "The brand of TFI if it is working properly doesn't make much difference"
You got it right...
 
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