Boost Launch Issues

CJimmyG

CJimmyG

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Joined
Aug 26, 2011
Messages
37
Hey guys, I've tried searching and I can't find much. When I boost launch, my truck will only build 15-18psi of boost. When it starts to light it will spike to 20psi then drops down. Anyone else ever had this issue?
 
Your transmission has a break over acceleration deal. Get trans tunes and it won't do it
 
Lmao Subscribed. Hey good luck with the boosted launch OP. The last autp 3rd gen i tried to do a boosted launch in threw a check trans light and that was at about 10psi. Im suprised your trans hasnt taken a crap on you.
 
Put smarty tq setting on 4 and shift defuel off, that should take care of it.

Lavon
 
I bought the truck because I was told it had a built trans, then I met the guy who built it so it's sort of built. The trans has been really frustrating.
 
I tried that. Smarty TNT on level 9 shift defuel off torque level 4, still won't build over 18psi
 
I guess not. Thanks for the heads up. I'll see if that helps.
 
When it does launch at 18psi, it doesn't pull as hard as when I brake spool in 2nd then lock up the converter. Would it be possible to be slipping the torque converter when it locks after a launch?
 
smoke machine said:
18psi should leave pretty hard. Much higher I see broken parts as the outcome
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It doesn't. At all. His silver bullet isn't even lit hard until 20psi. The 5400ft elevation doesn't help either but when I had that charger on my 12 valve I launched at 25psi and got 1.7 60ft's(that's all the trans would hold) his truck is a 2.2-2.4 IIRC. It feels like torque management is still on. Even though it's shut off on the smarty.
 
WILD_PHIL said:
Lmao Subscribed. Hey good luck with the boosted launch OP. The last autp 3rd gen i tried to do a boosted launch in threw a check trans light and that was at about 10psi. Im suprised your trans hasnt taken a crap on you.
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:doh:It's got valve body work, a billet triple disk converter, billet input. It's not stock. I'm guessing yours is.

:stab: There are many 3rd gens out there launching very hard.
 
duck_04 said:
I've cut 1.7-1.8 60's at 14-16psi
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I have to on my old 57/65/14 but like I said elevation is a killer on sloppy chargers like silver bullets. Luckily the billet 66/71/14 is going on his truck next week.
 
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Friday's private test and tune at the track gave me the ability to try nearly every different smarty combination and when I turned my shift defuel on but kept tq at 4 my truck acted exactly like you describe, would only build 18psi. Turn shift defuel off, tq4 and I could take boost where ever I wanted, i tried one 22psi launch and it just spun bad.

Are you for sure reflashing SW9 after adjusting your options on the smarty? I would recommend taking the smarty completely back to stock then adjust options to shift defuel off and tq4, tm3, rp4, and reloading SW9 and see if anything changes.

Lavon
 
I cant leave over 15 psi with a 66/74/14 or it just blows the tires off, at 18 I wouldnt be going anywhere. I have efi, but even with my smarty I had no problem launching. I'm not sure if I would run the torque on 4 sounds like a lot of broken parts. I think I need different tires, this was on 33" at's
 
Valair1 said:
I cant leave over 15 psi with a 66/74/14 or it just blows the tires off, at 18 I wouldnt be going anywhere. I have efi, but even with my smarty I had no problem launching. I'm not sure if I would run the torque on 4 sounds like a lot of broken parts. I think I need different tires, this was on 33" at's
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His is on 35" m/t's. Like I said before sea level and 5,500 ft is vastly different sloppy mediocre built chargers are laggy here. It NEEDS to launch at atleast 20psi to get decent 60 foots with that charger. I ran the same one and like I said I left the line at 25 psi.
 
Well got my billet 66/71/14 back, put it on, tuned it (set adjustments then downloaded tune) and it ran great. It would launch at whatever I wanted. Thanks for the help guys.
 
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