xspsi6

iTrader: (31)

It only works on the sc400 as the sc300 does not have the same trans.

bradg

Tried it, liked it, put the switch in the console. Anyone have issues in the longterm ?

Clean400

iTrader: (2)

Thanks for the info. Was always curious about that.I have this mod on a switch. I want to send a 5v signal only when the transmission is downshifting into first to avoid the harsh engagement. What's the easiest way to do this? I'm ordering a megasquirt 3x soon and I just received my supra stick. Maybe I can so it with one of these? Maybe some sort of window switch or tach adapter would work?

Clean400

iTrader: (2)

None so far. On a switch it's perfect. When coming to a stop with the mod on sometimes it makes a small clunk. When I want performance driving I just switch it off and when I want comfort rolling to a stop I can switch it back on. It would be nice to automate this with a switch so you could have the best of both worlds.

The small clunk I'm referring to is barely noticeable, but I'd rather not have that it doesn't sound natural. Probably doesn't hurt the transmission though. Usually I just cruise around with the switch ON so I get smooth driving.

xspsi6

iTrader: (31)

I don't get the clunk at all however I have polyurethane diff mounts which is where most of the clunk is most likely coming from.

Clean400

iTrader: (2)

Ok. I'll put some poly dif mounts and see what happens. I'll do it when I install my new diff. Thanks.

xspsi6

iTrader: (31)

No problem and usually the diff mounts are very often over looked.

JasGS350

iTrader: (7)

Did the mounts work?

ZcarBri

Hey Guys-

Was bored this morning so I thought that I'd try this out-

Does seem to get 'er on quicker from the start when driven aggressively - However, I've not seen the OD light flash yet - but this was after only a few runs on it-

I did experience the slight hesitation in shifting that a few others mentioned - but as I run it, this seems to change a bit?

Not sure if I'll leave it disconnected, will give it the day and see-

By the way, this was done on a '93 SC 400 auto with MEGA miles on it-

Should the light flash right away?

MooJohn

If you cut the wire at the ECU you'll never get any sort of warning light -- on the OBD1 cars anyway.

Mine will stay disconnected forever. It's how the car should have been from the factory.

Clean400

iTrader: (2)

So I put in the new poly diff mounts (among other things). The new diff mounts have removed the small clunk I was experiencing.

To be honest with the Transgo shift kit on, I can't tell the difference with the 4th solenoid mod on or off ( I have it wired on a switch) . I'll have to test at a drag strip to see if the 4th solenoid mod nets me any changes. Unfortunately I will probably only be able to do this in July, and I possibly might not have time and it would fall back to September.

MooJohn

Remember - it changes more than how it shifts - it actually wastes power (slips) if the ECU wants it to, like at WOT in first or a downshift into 2nd to pass. The transgo may raise pressure high enough that the solenoid's bleed doesn't affect it as much.

USMC

Thanks to KC and all the others, for all the time, research, effort and willingness to test this mod and report back your results for the benefit of all of us!

Ok, I have read every post from the beginning through today.

I have a '96 and one thought I have had about making this work with OBDII, would be to disable the #4 solenoid by physically plugging or restricting the port that feeds it, and still allowing the solenoid to function as normal.

The ECU should see no fault, but the solenoid would no longer be able to dump the pressure when it's needed the most.

This would be a semi permanent method, that would require dropping the pan and maybe the valve body to perform the mod, or to undo it.

If going that far, might as well install the Transgo 340 HD2 shift kit as well, and if going full Race Car, might as well go for the Hot Rod shift option too.

Now, what happens if you do all this plus shim the the two accumulators, explained here:

http://www.supraforums.com/forum/showthread.php?267655-How-to-make-a-a340-last(56kers-take-a-nap)

This is an excellent link to read up on.

Let me know your thoughts please.

I'm due for a transmission service, so strongly thinking about the options and what direction I want to go.

I used to have a 1970 Chevelle with a B&M TH400, full manual shift, reverse shift pattern, full competition internals, and it was a blast! Drive it like a stick, let off the gas, shift, no harshness; jump on it, shift at 7200 and all Hell would break loose! Two black strips four car lengths long from 1st to 2nd, and another two black marks when shifting from 2nd to 3rd.

Of course, it could turn a 1/4 mile in 11.72 @ 126 mph. Gotta love the LS6.

But those days are gone and now I'm just looking for a very strong shift capable of barking the tires 1-2 & 2-3, better launch and although the higher stall converter adds an improved launch, wanting to avoid going to that step for now.

Clean400

iTrader: (2)

The Transgo Shift kit comes with new metal rods and springs so you don't have to shim anything.

Basically it's a professional shimming kit plus modification to the valvebody.

If anything start with the Transgo kit on Truck setting. If that's not enough then gradually move up to Hot Rod.

And for the high stall torque converter you barely notice a difference in day to day driving. Still drives supersmooth. But when you stall it up you definitely get more go off the line.

StryfeS13

I have a 92 SC400 and disconnected the switch under my car...took it for a test drive and it felt amazing! No more bottom end bog, just floor it and it goes. (even peels out!)

However, now my O/D light is flashing (normal it seems), and it isn't driving like it was when I first disconnected it. I can't get it to "squat" anymore..it's just like it used to be, when the plug was connected.

Any ideas?