Automatic Speed Limiter/Governor

[schroder]

Ok guys, I've searched and searched. Nico, Google, other 240 forums and cannot find an answer. I have a 90 SOHC auto and am trying to find out if there is a speed limiter and if so, how to remove it. All I can find via searching is Auto ECU into a manual car. Or unplugging the 4th/5th gear sensors and cliping a wire to the ECU from the speedo. The reason I'm trying to find out is because over the winter I'm planning on putting together a turbo kit and getting it on the motor. The car is my toy and track car, and I don't want to risk pegging speed cut in the 1/4. Any help you auto guys (or Nissan Experts) can provide would be greatly appreciated. Thanks!

[badbob2121]

most aftermarket engine management software will remove the speed cut

what do you plan to use for this build you speak of?

[biggie]

Auto ECU has no speed cut.

[schroder]

Biggie: I know the ECU has no speed cut, but I thought I read somewhere that it was because it was governed at the TCU. Is this not true?

BadBob: As far as the build, it'll be posted on here and on another KA forum (I have no idea how this forum is on speaking about other 240 specific ones ) Plan is still realllly rough. I have a good friend who rebuilds/customizes turbo chargers and has offered about 5 different ones for testing to see which fits the stock converter better. He also does all my porting for me so, I know the head will be cleaned up some. I'm looking for a basic 300-350whp and it'll be used mainly at the local track to compete in bracket. I figure once I create a build thread, it'll probably be titled the underdog due to peoples feelings on the SOHC and Auto 240s in general. But here's what the original plan is, with a few things (engine/body) health dependent:

Some variant of a big 16g turbo (probably going to be a 20g turbo shoved in a 16g housing)
Mild Port
Gladman Mani
O&J Cam - probably stage 2 hydraulic
Factory refresh (new pistons, bearings, rings, hone, gaskets, etc)
255 FP (already installed and running great)
Uknown ECU right now. I don't want to drop the money on Nistune as it can really only compensate up to 880's or so, and I want room to grow in the future as I plan to build the motor once I figure out what the main areas to address are.
PLX wideband
3" exhaust (have it installed)

I'm sure theres a ton more, but right now everything is going to be geared around the stock converter and spool charachteristics. Most of the tracks near me are 1/8th mile, so having a great top end with nothing out of the hole isn't going to work for me. But I also plan on running in some events that are 1/4 mile events on the East Coast, so the speed cut could kill me there. And since I haven't had a boosted RWD before I need to figure out what areas need addressed (myself AND the car) before I start putting cash into it without really knowing where it should go. The biggest downfall with the car right now is rust. The frame rail is basically swiss cheese on both sides right where it starts to tuck under the car, and theres plenty more elsewhere. I can fix it, but for the cost and labor to do so, I don't know that I want to. I've got a friend with a 5-speed coupe that I can get get for a good price, but I've always wanted an S13.5 on a hatch...but I really like the coupes. I've got time to make my decisions as my daily needs some attention first, but with the way things are going at work I should be in a really good place at the beginning of the year

[Hoffman5982]

Biggie is right, there is no speed cut, or alteast my first auto s14 didn't. It could reach a whopping 135mph down a fairly steep hill.

[schroder]

Thanks man. Does the S13 not have one either then? Thanks again for all the help!