Manually locking the converter

[87-WE2]

First of all, I did search & was unable to find anything.

I know many lock the converter manually using a switch during racing. Is it as simple as installing a switch in between the proper terminals on the ALDL port and flipping the switch when you want the converter to lock?

I feel like I should be prepared for some ridicule here!!

 

[TexasT]

Yep, but it really accelerates wear on the converter clutch. It really wasn't designed to be locked during acceleration. Be warned.


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[87-WE2]

We're talking a few passes at the track, maybe two trips a year. When you say accelerates wear - you talking a couple of passes and it's toast, or more than that?
Would it be better to lock the converter in "D", or let it shift to "OD" and not lock the converter? I've only trapped about 104 and that was screaming at the top of 3rd - I've got to get the RPM's down in order to go faster at the traps.

I have a feeling a new transmission and converter are in my future anyway. If / when it gets burned, then I'll be going NL and won't need to worry about it.

 

[TexasT]

I know people who have locked up regularly and it goes. Others it just doesnt last. It is a "crap shoot".
Lock it up, you will get your tenths. Just not a long term way.
I've trapped 105 with a very stock setup and g60-15 m&h stickies.
I'm not discouraging locking the converter, just pointing out the stock converter is short lived when you lock it.
Maybe a taller tire gets you there . I like a m/t 28x9 slick.
Launch it hard and pick up tenths.

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[87-WE2]

The DRs I have only have a few passes on them, but the next set will be taller. And be m/t. Not thrilled with the bfgs.

I guess I'll get a switch and lock the converter and see what it nets me.

 

[GBGN1]

Dan locking up the stock d5 convertor over time will lead to failure. Which might put unwanted metal in your trans. With the convertors these days there's no needs to lock up converter early. That was a 90's thing. The ptc's couple so well that there's no need to lock up. That's why no one really uses a Lu convertor these days. Save your pennies and get a ptc and never look back.
Brian

 

[87-WE2]

That's the long term plan - trans and ptc NL. Just trying to get a few more mph on the big end before doing that. I may throw some 28" tires at it when these bfgs are done to see what happens.

I have a feeling my trans is going soon. Ever since cranking boost up to 25, it seems like the 1-2 is slipping a little.

 

[89mulletbird]

You should be able to calculate your % slip at WOT by using a MPH/RPM calculator. I have an Art Carr 9" lockup and at 5500RPM in 3rd gear I was running 103MPH unlocked. At 0% slippage MPH would be 120MPH. My slippage is 17/120 or 14%.

I just ordered a new PTC 9.5" NLU converter from Dusty. I'll be able to see how much slippage the PTC has. From what I've read it should be around 6%. That would give me another 10MPH in 3rd gear and let me hit 120MPH @ 6000RPM with a 26" tire.

 

[bison]

You should be able to calculate your % slip at WOT by using a MPH/RPM calculator. I have an Art Carr 9" lockup and at 5500RPM in 3rd gear I was running 103MPH unlocked. At 0% slippage MPH would be 120MPH. My slippage is 17/120 or 14%.

I just ordered a new PTC 9.5" NLU converter from Dusty. I'll be able to see how much slippage the PTC has. From what I've read it should be around 6%. That would give me another 10MPH in 3rd gear and let me hit 120MPH @ 6000RPM with a 26" tire.

At 6000 rpm your mph should be over 130mph