I have been hearing alot about a third gear boost launch out of a manual trans... how is this performed, anything bad about it? just want some info so i can try it once hahahahathumbsup
i tried it in my dually i must not have been doing it right cause it melted the clutch, but the truck also had 200k on it but when it left it left hard, i only had a van aken smartbox and afe intake so from the looks of it your truck would leave pretty hard
What are the instructions on performing this operation? I really wanna try it. My buddie has an auto and boost launches at 15pounds, thats how he always beats me when we race, I would love to learn how to do this and suprise him big time!
Well I wouldn't suggest trying it with the stock clutch...AT ALL. Thats just asking to replace it. But are you wanting to lay rubber or are you talking about just getting the rpm's high enough to to stick and haul it?
I can also say dont try it with stock clutch or you will be putting a new one in sooner than later its not even recommended on a aftermarket single disk. You really need to have a dual disk to be able to do it well and for it to survive.
I do 2nd gear launches...but boosted launches....haven't had one yet...Don't do it with a stock clutch!!!...I rev to about 1300rpm and pop the clutch...but boost isn't immediate..takes a sec. not like an auto.. where you can stand on the brake and get boost up before breaking the tires loose...Curious here also how to accomplish a boosted launch on a man trans...I imagine you have to have some sort of wastegate fooling or adjustment...so you can build boost with out it in gear.....
ok, I understand I shouldnt do it, but I plan on a dual disk within a month or 2, just want to try it now. Any instructions... I want to hook up. I would guess i should be in 4 high, 3rd gear... then what?
to build boost you have to load the engine, and the only way to do that with a manual is to bring up the rpms and while holding the brake slowly let out the clutch enough to load the engine and build boost.
Basically smoke the clutch till you have boost and giver chit...
You have to work all 3 pedals at the same time. Throttle and Brake with your right foot and clutch with you left. Hold the Brake, Give it throttle with your toe and slowly start to let the clutch out but hold the brake until it starts to lug the engine and build boost. From there Let her go and hold on. (also could end up having to pick up pieces out of the middle of the road - KABOOM!)
I do 4th gear boosted launches in mine I don't lift off the clutch until I see over 40PSI....
Just go full throttle, then let the clutch out some until boost starts coming up, then let the clutch out more, and more, until you finally just lift your foot off the pedal.
I'll get a video of it.
A factory clutch won't handle a 3rd gear launch, even more a boosted launch, you'll be alot slower boosting a 3rd gear launch than a high RPM clutch drop in 2nd.
If you aren't pushing 400+rwhp, trying to do a boosted 3rd gear launch is just a step backwards. Use RPM and inertia of the engine (rotating assembly) to get scooted off the line. Lots of throttle, lots of RPM and just slip off teh clutch. You'll find a sweet spot to dump the clutch at to avoid too much wheel spin...
I agree these high HP single disk clutch's dont like to slip. And from what I'v heard if you do slip them a lot they will eat up your flywheel really fast.
i have doen a small boost launch in 2nd gear with my ceramic/ceramic. it actually was slower than just dumping the clutch. i do a little drag racing in on the dirt so i start out in 2nd gear and just dump the clutch. that seems to work the best and dont have to worry about burning up the clutch. i need a DD and the bigger input shaft and hydro upgrade. o i cant wait
Okay Buddy, You just added to my video requests. Now I need a speed shift video.
The Dual disks shift about .1 second slower than a single disk, but the difference is, after the shift the clutch is 100% engaged and it's not going to slip for .2 seconds after you lift your foot off the clutch.
On this saturday or next I'm gonna get yall some video.
those are awsome videos. I wish i knew how to take a video off of my phone and put it on here. I have one of my buddy doing a 4th gear hole shot in front of my house at about 4K RPM. It was wicked. P-pumped 24V with HX-60
Boosted launches are not a good idea on any single disk or small input shaft unless you have another ride or like to walk home. I would say doing one with a 4wd truck in 4wd is alot harder on componets than doing one in a 2wd dually as well since there is no weight back there. But you do one with a truck in 4wd and alot of componets have to take alot of abuse but its like a rocket off the line since the front tires usually dont spin or if they do its not alot with all the weight of the engine on them.
ok, so against your guys' advice, I tried a 3rd gear boost launch, got it up to 20 lbs, and dumped clutch and brakes... didnt do much, clutch roasted lol. ok so then I tried the 2nd gear dump in 4 hi. dry pavement at 3000, all 4 tires broke loose, and it really threw me back.... just wish i had an input shaft and a dd... how hard is it on stuff doing these kinds of dumps in 2nd gear?? cause I can see it hurting alot, or are these trucks build to take it.
Just like any performance activity, keep doing it and you will find the weakest link. Replace that, do it some more and you will find the next weakest link. But no mistake, you will break. Might be an input shaft, clutch, wheel hop might break a u-joint, ring gear. It all moves and can all break when abused.
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