I’m just curious how many of you have dyno’d your car with the converter locked?

I got my car dyno’d this past weekend, and I wasn’t planning on locking the converter, but the dyno operator said it was needed. He said as long as we did it a certain way, it wouldn’t damage anything. I manually shifted the gears using HPTuners VCM Scanner, and then once in 3rd gear, I locked the converter and we made a pull.

I’ve heard from multiple people this is really hard on the converter. I have also heard from multiple people this is fine for the dyno, just don’t lock the converter @ WOT on the street.

I have a Yank SS3600 converter, and Dave @ Yank says NOT to EVER lock the converter at WOT.

Just trying to see what everyone else has done!

 

I've wondered the same myself. If it's not locked going down the dragstrip, I don't see why I'd lock it on the dyno.

 

There are convertors specifically engineered to be able to lock them at wot , multi disc billet I believe. Seen a link in this section where 50-60 hp and 70 ft lbs were picked up by locking but that was a 600 hp turbo build with a vertor built to be locked at wot I recall.

with a convertor not designed to be locked at wot you might get a free pass for a one gear dyno pull and the operator knows it will provide the magic number for you but I wouldn't do it again till you get some advice from some convertor builders , sounds risky...

 

Last time my car was tuned I had the tuner NOT lock it. Only multi disc converters are meant for that and even that's been debatable depending on what sponsor you talk to.
One thing I learned is that there's plenty of talk about locked dyno #s but I haven't read a whole lot on this board about the risk of locking at WOT. IDK if its ignorance or people just want the higher dyno reading but I told my tuner I don't care about locked #s so don't do it.

My previous stall was a ss3600 and at this time I was ignorant of the risk of WOT lockup. It was locked on the dyno and no problems but now I know the risk. Probably will never do it again.

 

I recall threads where the OP said the dyno operator locked the converter and now his lockup is slipping (or worse).
The dyno operator wants to improve his "reputation" by posting a bigger number while risking your converter and trans. I would not.

As mentioned, a much more expensive triple clutch converter is designed to be locked at WOT and that would be fine on a dyno. But not a typical single clutch converter.

 

Yep -- Not doing it again.

The triple disk converters are much heavier, aren't they? I highly doubt one would be beneficial in my car.

 

I'd be worried, especially with a smaller diameter than stock converter.

BTW, I was shocked to find that the stock tune from GM for my LT1 4L60E has the converter locking at WOT by default, but of course that's with a 12 converter.

 

Theres a well known sponsor that says even a triple disc will fail eventually from the discs warping. So pick your poison I guess.

 

that depends on the 2 converters your comparing...

if your comparing apples to apples like our SRL and SRL-3 series which are both 245mm furnace brazed, billet back, billet piston, and so on. then you're talking about the additional weight of 2 triple disc friction plates that cant weigh more than a pound together.