boost limiter?

[SuperHO]

K....so me and JoesSho were yappin at lunch today, and we got hit by a great idea....

..after getting up off the floor, we started talking a lil deeper into it.

How hard would it be for some of you TwEECer guys to design a program for the turbo/blower crowd that'd limit boost in 1st and 2nd gear via electronically controlled waste gate....then allow full boost in 3rd and beyond. Ya know, something to help with that overrated thing called TRACTION?

Dunno...let's discuss this....like gentlemen....keep the ******** comments to yourself, cuz I think something like this is doable and perhaps even neccessary.

So.....let the figuring begin!!

 

[spaul2005]

that would be great too bad that i dont know anything about the tweecer cause im wait to get mine..

 

[SHO92]

The problem with that would be the EEC has no way of knowing what gear you are in. Most newer cars use this idea though since they have the needed sensor. A lot of times it's done for timing settings.

It might be able to be made as a speed dependent variable, but that wouldn't work 100% either, since you have have the same MPH in several different gears.

 

[SuperHO]

...already thought of that.....it's kinda prehistoric, but it's simple enough.

A simple activator stuck down on the shifter or the center console so that when the shifter hits it when shifting to third, it activates full boost (got the idea from a buddy of mine with an SRT-4). Seems archaic, but I don't see how it couldn't work. it'd be a matter of setting up the switch to an actuator on the wastegate with an arming switch somewhere in between.

 

[Axianator]

As much as I hate to be the bearer of bad news and/or shoot down a potentially neat concept, thought or idea, Bill is right on this one. Not only do the '89-'95 V6 MTX computers lack the necessary inputs to (properly) achieve such a useful feat, but none of the '89-'99 SHO computers possess the necessary programming to properly control such a system or modification. In order to properly implement this type of modification, you would need to possess the ability to rewrite and recompile the factory code yourself, a feat that is currently reserved for factory calibration engineers, those with really good connections and those with lots of time on their hands.

 

[gmorrell]

Even beyond EEC not knowing what gear is selected, EEC has no idea what wheelspin looks like. Knowing when there is wheelspin requires wheel speed sensors on the driven and undriven (reference) wheels. This information can be gleaned from an anti-lock brake system, and pretty much all OEM TC is accomplished by making the ABS and powertrain control modules talk to each other.

Racelogic http://www.racelogic.co.uk/ has systems that interface with a vehicle's existing ABS and provides torque management via shortening injector pulse widths or pulling timing on vehicles lacking fuel injection. They're spendy, but they work.

Gary M.

 

[SinisterSHO]

There is a progressive nitrous controller that actually counts gears. If you could wire that up in a manner that would activate a waste gate instead of the nitrous solenoid, that could probably work. But it is a 700+ dollar controller.

 

[SHO92]

The system could be created to limit boost using the gear lever, like SuperHO suggested, it just wouldn't have any type of interplay with the EEC. You could make a seperate box that control a boost control of somesort, be it a wastegate, BOV, etc. That is possible, but like Gary said, it wouldn't help traction in anyway, other then limiting boost.

Sinister, any idea how it "counts" the gears? Do you have a link to the product?

Those racelogic units sure are cool. If only I had lots of money.

 

[SuperHO]

The system could be created to limit boost using the gear lever, like SuperHO suggested, it just wouldn't have any type of interplay with the EEC. You could make a seperate box that control a boost control of somesort, be it a wastegate, BOV, etc. That is possible, but like Gary said, it wouldn't help traction in anyway, other then limiting boost.

That's exactly what I was thinking.....you shouldn't need to tap into the ECU to control a wastegate. You just need something to send a signal to an acuatator to let the wastegate know that it's time to do something stupid...

 

[ManySHOs]

Racelogic is the way to go. I actually looked into them a few years ago when I was interested in traction control for the SHO. (I have no idea why I was looking)

Ian

 

[sho_sc]

That's exactly what I was thinking.....you shouldn't need to tap into the ECU to control a wastegate. You just need something to send a signal to an acuatator to let the wastegate know that it's time to do something stupid...

Is there anyway to just "manually" control the wastegate, place a switch on the gear shift? Then is there anywhere you could place the wastegate in the S/C tubing that would not interfer with the pressure stream causing the MAF to go nuts?

 

[Toolman]

You guys are overthinking it. Any number of EBC's will do exactly what is being described. You can not limit boost to lower than your WG spring though, so start off with a soft spring.

 

[SinisterSHO]

The system could be created to limit boost using the gear lever, like SuperHO suggested, it just wouldn't have any type of interplay with the EEC. You could make a seperate box that control a boost control of somesort, be it a wastegate, BOV, etc. That is possible, but like Gary said, it wouldn't help traction in anyway, other then limiting boost.

Sinister, any idea how it "counts" the gears? Do you have a link to the product?

Those racelogic units sure are cool. If only I had lots of money.

The system is setup via a palm, and I believe with the intial setup, you tell it what rpm you shift at. Everytime you reach that rpm, it counts it as a gear. I dont know if/how it works if your already moving, though.

http://www.nitrousexpress.com/Pages/Maximizer2.htm

 

[SHOmethe$$]

There is an option for Zex NO2 users, I am thinking about trying one:
Traction Control Window Switch

 

[Lupo]

You could do it mechanically pretty easy.
Just have a boost limiting system that is "on" all the time (I currently have an electrically activated one thats limits me to 13psi). Have microswitches that activate when shifter is at the end of it's throw for 3rd, 4th and 5th.
These microswitches would cut the ground to the boost limiting system, disabling it.
Of course this is with a S/C, and my homebrewed boost limiter.

 

[1slickRED89]

Is there anyway to just "manually" control the wastegate, place a switch on the gear shift?

yeah, works great it's like 'weee', then 'WEEEEEEE'.

 

[yamahaSHO]

It seems like a great idea to be able to limit boost in lower gears, but with a setup like mine (SHO Shop), it would make difficult placement when you have to work around the MAF. Even with my by-pass valve set to the lowest setting ~3 PSI, it doesn't vent any boost even when I was hitting 11 PSI. The placement on these pipes from the SC to the MAF doesn't really vent boost well, and has Ransom has stated, the MAF reading would suffer.

Another idea for a supercharged setup would be able to limit the amount of air the supercharger sucked in on the inlet side. If you could reliably, and safely fab something up that would restrict the air intake at will, I think that would be a better option. Turbos have it much easier when they can bypass the exhaust to refrain the impeller from working so hard.

Although, my boost limiter is my right foot.

 

[twr]

Although, my boost limiter is my right foot.

Exactly what I was thinking, loose traction... lift off a little. I know easier said than done.

 

[ManySHOs]

You could do it mechanically pretty easy.
Just have a boost limiting system that is "on" all the time (I currently have an electrically activated one thats limits me to 13psi). Have microswitches that activate when shifter is at the end of it's throw for 3rd, 4th and 5th.
These microswitches would cut the ground to the boost limiting system, disabling it.
Of course this is with a S/C, and my homebrewed boost limiter.

The shift gate is inside of the transmission. How would you mount these microswitches?

Ian

 

[Lupo]

The shift gate is inside of the transmission. How would you mount these microswitches?

Ian

I'd mount it at the shifter, not the shift gate. under the boot.