Opinions on Nitrous to get me into the 12s or low 13s? What's the max dry shot the engine could handle repeatedly for over 100 passes? I might have a source for a good deal in the future.
You can't run a dry system on a carbureted car, you have to introduce fuel with the nitrous. "Dry" nitrous is for fuel injected cars, because the EFI can add it's own fuel when it reads the A/F is going lean because of the oxygen added from the nitrous oxide. Most HEALTHY stock engines can take 100 hp.
Ok that makes sense. Only reason I didn't think of that is wisdom teeth painkillers. Dry shot with no wet would put holes in everything.
Exactly. The nitrogen in nitrous oxide is only there to make the oxygen more stable and safer, and essentially just goes out the tailpipe after the fuel and oxygen is burned in the cylinder. Remember, if you do go with nitrous, without an electronic timing controller you'll have to retard your timing for normal driving so it's at a safe level when on the bottle. I always did 4 degrees retarded at 100 hp, 6 at 150 hp. I believe that's plenty safe, but it does cut down on your daily driving power a little......That said, it's sooooooo much fun. Your torque goes up more than the HP, and on a dyno the boost is almost straight up and down. As in, if you're at 350 HP and 450 ft-lbs. and turn it on, your power goes to (give or take) 450 HP and 600 ft-lbs. in a matter of a couple hundred RPM. I'm a nitrous junky.
YESSSSS Can I like this post 10x? Nitrous that bad boy. Get a plate system. Wet. Plate goes right under the carb. Fuel and nitrous are shot in when activated. I have used the edelbrock spreadbore plate kit on a low compression 350. Went from 15s to 12.9 in a skylark. On a 100 shot. I'd say start w a 50 shot and build from there. For the timing retard you can use a retard box (I've got the one I used) that activates only when the nitrous is activated. Do it. You won't be disappointed. I believe nitrous is one of the best bang for the buck mods, when used appropriately.
Fired off the carb to Ken for the night for a performance recalibration. He's done a great job in the past, no doubt it'll continue. Riv wouldn't idle on the idle circuit, instead stinking up the whole garage, had no power beneath 2000(despite the cam, I know better), and the exhaust cackled when I let off the throttle at high rpm(possible lean, or burning excess fuel?). All things that can be fixed
Just bought the Dynomax 17219 Ultra flows off Amazon, not a terrible deal. Prepping for the install of the TA system over spring break. Then we'll take it to the track and hope.
I would stay away from Nitrous if I was you. If you don't have everything right, you'll hurt the motor. Nitrous liberates extra oxygen in the combustion chamber. Without more fuel, you can go lean, and as mentioned, you'll have to retard timing with it. Running lean and detonating the motor at WOT is the quickest way to take out a motor.
I'm feeling like I need a rev limiter. Got it to idle at 800 today thanks to Ken, all the modifications are working great. I just have to figure out how to get it to idle cold, adjusting the choke and fast idle screw. It still feels rich and lethargic, going back to 74 main jets. Not today, my mouth has just about stopped bleeding, so I'll wait. Being on this cycle of drugs isn't doing me well. Turned up the adjustable vacuum modulator 4 turns clockwise, should be higher shifts now, measurably. It's shifting at about half the stall speed of the converter, so it feels awful. I'll get the governor set up at some point soon, I just need a dry day for the ground to really wring it out to test shifts.
The vacuum modulator will only affect shift points at minimum and part throttle. The adjustment is limited. To affect WOT shift points, you'll have to modify the governor. Make sure the switch pitch converter is working properly. It should be at high stall at closed throttle idle, off idle it should immediately go to low stall. At approximately 60% throttle, it should go back to high stall. If the converter is at high stall under light throttle, it can make the car feel lazy.
Also make sure kickdown is working. It affects line pressure and will cause a lower rpm full throttle shift if not working.
Crap, that's exactly what I meant to do but forgot to write. Thank you! There's a diagram in my service book that I've been too busy and knocked up to look at, but I know exactly how I need to attach it to get my downshift back into place.
X2, the ST400 will short shift at WOT if the electrical downshift is disconnected or not functioning for other reasons.
Totally agreed Larry, part throttle is where I'm worried about right now. I know the distinction between gov and mod pressure and modifications. WOT I will worry about soon, once I attack the part throttle mod pressures.
