Currently have a overly tight converter spec'd for a much larger motor. I threw a 4.8 in the car to finish out the season while I finish building up a 6.0. With -20* of timing I can manage 4lbs of boost and 3000rpm on the trans brake. When I release the brake boost falls and the car bogs to 4k before the turbo lights off. Recently threw a n20 dry kit on I had laying around. Using Mega Squirt to control this and cut the nitrous off at 4k. Using a .035 jet (maybe 50ish hp?) I've still yet to fill the bottle and plan on disabling the anti-lag/timing retard on the 2step. Question is, if I'm still having issues. Should I just keep upping the jet size? Or should I incorporate some sort of antilag in addition to the nitrous? I can add or subtract as much as 40* on the brake. I'd think hanging the valves open with the nitrous going would just add to the anti-lag effect? Or would this possibly dangerous? If so...why?

 

Do you have a window switch, you could set the nitrous to come on right after you launch above your 2step rpm and then have it shut back off. Ie if your 2step is at 3K have the nitrous window switch at 3200-3500 etc that way it shuts off after that, just make sure where you have the nitrous shut off is under your min drop rpm during shifts so it doesn't come back on during the run.

 

I do, using the mega squirt to control it. I think I'll need to build more than 4lbs to launch this pig. I can try it your way though. I currently have it set to come on at 3k and shut off by 4k. That way it should kick on well before the launch to build boost. I see an 1800rpm drop on the shift! So this converter is silly tight for this motor. Shift at 6800.

Waiting on one more fitting to test it. It may work fine all on it's own without the anti-lag. I was just wondering if dropping tons of timing with the nitrous online was likely to hurt anything?

 

I'm not a fan of loading up with nitrous at the line, small shot should be okay though as long as your not sitting on the 2step long.

 

Since I'm using the TPS position and the RPM window I can stall the car up a little under 100% TPS position. Then wait till the lights start to drop and activate the N20 at 100% TPS. Sounds a little tricky to "master" though. I was hoping with the N20 and added boost on the brake I could stall up much higher than the 3k I'm hitting now.

I defiantly like your idea of hitting the nitrous hard right on the brake release. It would make staging and launching much easier. I also think it would require a much larger shot to pull the car up through the RPM since the car bogs below 3k when the brake is released the way it sits now.

 

Subscribed! If it were me I'd set it up on a wot switch and push button and try launching off the foot brake first. What 2 step do you use for anti lag? Does it pull timing or do you pull the timing in the tune yourself? Not fimilar with the ms stuff so excuse my ignorance.

 

Usually end up pushing through the brakes well before you get to a good launch boost level if you don’t use the trans brake. Some setups are matched well enough to build boost instantly off the foot brake...I’m no one of them!

You can set the 2-step up however you want. I can set it to pull ignition and/or fuel at any RPM. It also has an input for desired timing/fuel while the 2 step is active. You don’t have to alter the timing at all. Anytime you hang valves open enough to let combustion bleed out into the exhaust people call it “anti-lag”. I don’t mess with the base ignition map, 2-step does it all.

 

Play time was cut short but after a little driveway testing I'm pretty optimistic. Was able to stall up past 4300 rpm and make 7psi pretty quickly. (with the exh dump closed) The jet was originally a 22 and I drilled it out to a 35. Looks like thats in the neighborhood of 60hp? This was with no fancy ignition tricks either. Hoping to head to the track tomorrow evening.

 

Good luck! Hopefully that extra boost and rpm will do it.

 

Seems to work well. I may up the shot to 75-80. Was able to build 13lbs on the brake and hit 4800 rpm. N20 was set to come on at 2900 and off by 4100. At 4180 I was at 6lbs, engine built boost on its on from there. Worth a 1.50 60' and it was spitting rain. Was on a 295 drag radial.


Pretty bad night over all though. Pulled into tech and shut down. I could hear the nitrous leaking past the solenoid into the motor. It wasn't wide open, but it was leaking pretty good. Let the car sit for 15 minutes or so. Then pulled the wires and cranked it for awhile. Then cycled the solenoid a few times. Solenoid seemed ok after that. Track got pretty crowded by then. First run was a test pass at gate pressure to see how it would act. Loaded up on fuel and botched the launch. 12.2 @ 134 on 11lbs. I shut the pressure off on the bottom WG port. This usually net me right at 20lbs. Launch was great but boost hit 29lbs and started breaking up so I let off. Third pass I opened the bottom WG port again and let 2 turns worth of boost into the top port. (guessing at this point.) Went 9.55 @144 on 18lbs. It was raining at that point so I cruised home.

#ad

 

Am I reading it right that you were pulling timing for an antilag strategy? On a auto car pulling timing usually makes things worse while trying to get up on the brake with a converter on the tight side.
When I used to run a 5 speed in my turbo 2.3 bird, I would pull 10-15 degrees out on the 2 step which would get the boost up quickly. When I switched to auto, I actually had better luck adding timing in. When I am on the transbrake floored at 2800 or so and 2-3 psi, I am around 38-40 degrees timing. I don't pull any timing until the boost exceeds 5 psi. I also use a 50 shot on a button to spank up the turbo and it gets it to 20-22 psi in about 1-2 seconds.
Your car is interesting for sure.

 

I've actually tried 40* adv as well. It did build the same amount of boost but took much longer. All of my auto anti-lag setups (built 4 now) work better with negative timing. Most people just don't retard it enough. 10-15* from the base map doesn't do it. That will just add some heat and works very slowly. You need to hang the valves open when your plug fires, then you'll get alot of combustion in the hotside.

Advancing the timing also helps spool a turbo but works in a much less violent way from my experience.