I lost about 2 MPH today with my 3600 stall. Right about 5200 RPM my RPM gauge stopped increasing & even decreased a bit right before the traps. What Am I seeing? Is the computer Locking it up when that happens? Any benefit to hooking up a lock up switch?

Thanks

 

You, my friend, have discovered the infamous OBDI high stall incompatibility!

 

Nah, I think his converters just locking up right before the traps, which isn't the OBD1 high stall problem. I would hook up a switch, and see what works good with your combo. It might be best to not lock it up at all

 

I would say when the RPM decreased the converter locked up. What RPM stall converter did you have before. What is the name brand you have currently that you lost MPH with?

 

That's actually not out of the ordinary when you put that big of a stall in a car. I've seen it happen on a couple cars until they went all out on the mods, then it helped.

 

I had a 3200 Vig. Now 3600 Vig. I think whom said maybe no lockup at all might be on to something..

 

If your not making enough power, some times locking up the T.C bogs you down instead of helping. You said your rpms dropped slightly, that sounds like its bogging down to me

 

See...Bigger ISNT always better

 

Sucks man, but it sounds like you've got some good responses here...

How were the 60' times like?

I think I'm going to stick to 3.73's and a 3200 stall..

 

what is a good stall speed for a stock?

 

with only bolts ons i was cutting 1.7 60' times on a 2800 Vigilante..

I plan to step up a bit higher to 3200 now that I have a cam in, but a 2800 is an excellent converter.

 

Sounds like you might have gone a bit too high of a stall.

What are your ET's now compared to what they were before?

How are your 60's now?

 

My ET was 12.3 to 12.42 out of 12 runs last October @ 108 to 109 mph. Tonight I ran a pretty consistant 12.43 to 12.49 @ 106.5 to 107 MPH. My 60' time went from 1.64's to 1.61's. If you go to the Drag Racing section you will see my post. I think I will need to not have the TQ Converter lock up at the traps & get my shift points upped to about 6400 RPM's. Right now It shifts about 5900 RPM.

Here is the Drag racing post I posted. Drag Racing

 

I installed on non-lock up switch on mine.
I gained almost 1-mph, what happens is the converter locks up at 95mph (computer controlled) and it could be that it is bogging the motor a little bit. I was trapping about 5850 now I'm trapping 6000, can't wait for the 3.73's to go in.

Basically you install the switch to un-connect the computer from the TCC solenoid. If you want to manually lock it up you would ground the TCC solenoid but in this case you would only break the connection to the solenoid thus not letting the PCM turn on the TCC solenoid.

 

My wild guess is that the stall is a little high for your car and that your shift points would be better set around 6000...

I only shift at 6200 on mine, any more and my ET goes up...