It works like a charm on Matt's old Fairmont with Microsquirt. Will be racing it this weekend and launching hard on boost.

 

I'm hoping I can spool my 106mm 427 with a stickshift with antilag and build wastegate boost at minimum.

 

I did this same thing with my old turbo car for the longest time. I too found the same issue that just adding timing, it would build 7-8psi very quickly on the footbrake, but it would flat line and wouldn't build anymore even after I grabbed the transbrake in the second beam at the track before the lights dropped.

I started talking to some of the guys in the 275 classes that ran turbo's and they all recommended once I got that 7-8psi of boost built to yank 8-12 degrees of timing out of it only after I had that 7-8psi of boost built. If I tried yanking that 8-12 degrees out before I had that 7-8psi built it wouldn't do anything and actually wouldn't even build anymore boost than it already had if I was below 7-8psi.

The first time I did this and pulled 8 degrees at 8psi it started popping and banging like it NEVER did before and I had 15psi of boost built from 8 within 1 second. It was like a totally different car the way it launched. I've recommended this method to everyone who has ever asked me about how to build boost and it's worked the exact same way for them every time.

 

Boost will tend to fall once the transbrake is released, the motor does not have enough mechanical efficiency to keep the turbine driven that hard.

 

Martin, that seems to be what I am getting with Matt's old car. I can build 7-8 psi at the track, but then it runs out of steam. I am going to see if he has any ideas on how to tweak the anti-lag in the MS, since I am not experienced with it.

Here you can see me working it yesterday, although the gauge is nearly impossible to read in these videos:

http://www.youtube.com/watch?v=5tsMW...ature=youtu.be

 

Very great info thread. Subscribing.

 

Damn! That tranny shifts reeeeeal nice lol

 

Damn straight!

 

essentially turning the turbocharger into a jet engine and intermittently feeding that jet-turbine fuel (hence the popping from hell). the timing (i think) is to get engine combustion to happen partly in manifold or to feed raw fuel into the blazing hot turbine housing and have it detonate thus driving the turbine faster.


would there be a way to introduce a small amount of fuel to the system and ignite it without using the engine as the 'combustion chamber'? these antilag setups have GOT to be hell on the engine as well as the turbo's.

 

Exactly, you are basically retarding the timing so far that the combustion event is happening in the primaries closer to the turbine.

 

I remember seeing an article about a rally car that had an injector and spark plug in the exhaust header leading to the turbo to dump/ignite raw fuel and really spool the turbo.

sounded like a bomb waiting to happen but it really made the car pull hard out of the corners.

very interested in learning more about how the tuning was done with the megasquirt! sounds awesome

great results

 

would there be a way to pull the timing out using a stock ecu or add a switch to the ecu to signal timing pull. Like maybe ground a knock sensor wire once you build the initial amount of boost?

Seems like everyone is using some sort of aftermarket unit to accomplish this?

 

You could trick the IAT sensor into thinking you had super heated IAT temps and have it pull the timing out via a button on the steering wheel.

I know a few radial guys with stock ECU's with LS engines that have a button on their steering wheel that if the car acts like it is going to go on the bumper, instead of peddaling it or shifting into second, they hit that button and it knocks 5-6 degrees timing out via the IAT timing table while shifting into high gear(2spd.) and most of the time it will bring it back down.

 

For true anti-lag you need a closed loop system that retards the timing as the boost builds. That way you can hold a static RPM and have whatever manifold presure you want. Obviously this is not something you can do in the stock ECU but it is used in race cars (WRC) with great sucsses.

WRC cars are pneumaticly operated manuals and they can sit in nuteral and make 45psi of boost with no load on the engine!

 

I have a 2 step, stock ECU and Hptuners. If my 2 step is set to 4,000 and at 4,000 the 2 step kicks in and I am at 7lbs of boost and it won't go any higher, why couldn't I go in the main spark timing table and at 4,000 and where ever 7lbs of boost matches up, then drop the timing -10 degrees there. I would think you could even drop it the cell above and maybe a couple below in case the boost is anywhere from 6-8lbs. I have an automatic and wanted to try this. What do you think?

I tested my engine today with the new PG and 3.42's. It builds boost really quick to 7lbs with the 2 step set at 4k but then it just stays there. Can I retard the timing or not? If so where exactly would I do this?

 

This is what I was referring to. I dropped the timing -10 degrees in the purple highlighted areas. Is the area that I am at 6-7lbs of boost if my 2 step is set for 4000? 6-7lbs is all I am getting on my logs. I just want to make sure that I am dropping the timing in the correct area.

 

done right, no. all you would be doing is building a very simple and inefficient jet engine. the spark plug shouldnt be needed for more than a second or two to get the combustion going. then.. feed fuel and enough air to keep it lit and voila... a tiny little jet engine attached to your engine.

 

I've seen a guy here with a Talon build 25psi with no load on the car very quickly .. their system has a setting for it... Black smoke filled the shop popping like crazy.. it was nuts.

My car would get to around 5-7psi if I got past that hump it'd be at 15 very quickly it was ramping up to that 5-7area that took a few seconds... I had a tight converter and also left on the foot brake. I was too chicken to use the Transbrake.
I've seen the anti lag.... I may need somthing like this to get the new setup to
build boost quickly. Interesting thread..
Thanks for sharing the results.

And leaving with 20psi? with total of 30 to go high 9's in a S-10? Somthing else is going on... restriction somewhere... what's the rear gear?/Stall ect... what's the MPH?
There is somthing off...is it still carb?

 

That's not how I would do it.

This is how I do it. I leave the main timing table alone and set it up for advanced timing on the footbrake to get boost built and then the timing I want down track under boost.

How I retard the timing on the transbrake to get more boost built after I've built 7-8psi like we're talking about here in this thread is with the AFR spark correction table.

This table references the commanded fuel multiplier currently commanded, and when that multiplier is commanded( I.E. a 1.0 fuel multiplier with a 14.7 Stoich would command 14.7 if your VE table is correct) it either adds or retards the timing value that you've inputted. This table works off RPM and the commanded fuel multiplier. SO to pull the timing out you want, what you would do is reference the fuel multiplier coefficient that you're commanding on the transbrake at 7-8psi at 4000rpm in the AFR spark correction table and input -10 in those tables. This will only allow it to retard the timing at that certain instance and no where else. That way you're not rolling down the highway and hit it WOT and end up pulling timing out where you need it most to get the turbo's lit and you don't have to constantly swap tunes because you've messed with your main timing table.

You can also use this table for adding timing in rpm regions that you know your car is slower to spool in while moving. Such as a M6 car that needs some help from 2000rpm-4000rpm in getting it's turbo(s) to spool. You can leave your main timing table alone and add in 4-16 degrees(using these values as an example) of timing in that 2000-4000rpm region while commanding whatever fuel multiplier you're commanding and add timing there so that the turbo's spool quicker and you get better transient response.

This is especially helpful for big single turbo M6 and automatic cars that roll race a lot on the highway and need boost to come in as fast as possible from the hit.

 

its called the Scooby Rocket box. Its actually an ecternal combustion chamber anti-lag system. MUCH better than a convetional bang bang antilag system and puts alot less load on the turbo and well as the engine!!!

In principle when the throttle is closed a bypass valve open and vents air into a chamber. THis chamber contains a fuel source (fuel injector) and a spark sorucce (spark plug). This containor then leads to the exhaust manifold. This effectively bypasses the engine and turns the engine into the mentioned jet engine.the key is acurately controling the turbine to stop it over spinning and catching it early enough so the jet stays lit. On WRC cars there are pretty compex electronic that control it all.

On another forum a guy got hold of a Scooby system and fitted it to his car. blow the gearbox on the first launch!

although harder on transmission they put a lot less stress on the turbo as the combussion event is happening in the chamber not the exhaust manifold!

Chris.