scared to launch

[josh2016]

i still have the stock IRS the only thing done back there is 4.10's, Eibach suspension with bilstine shocks. my car dynoed at 535 rwhp. i just had my tranny fully rebuilt by Pro Motion. the tranny can now support up to 800 rwhp. what im worried about is launching with a sticky tire on my IRS. I've watched 2 guys with cobras blow their IRS at my track with slicks and im worried about ending up like them. im not running with slicks but i just put drag radials on the car today and plan on going to the track this coming Wednesday. what is a safe rpm and tire pressure to launch at?? and is the IRS brace worth buying to avoid destroying my IRS with a hard launch? thanks for any help.

 

[MVD]

Why are you worried? Do you not have the money to fix broken parts or you do not want the hassle of fixing broken parts?

Either way, if you are scared then don't go to the track. There is no guarantee when racing with the IRS, I have seen cars leave off idle and snap axles or even down track while shifting.

 

[josh2016]

I have the money to fix it but i planned on using the money for a SRA sometime in the future. i still want to go to the track i just want an idea of what a good rpm to launch at and some info on the IRS brace

 

[P49Y-CY]

def do a brace so you don't crack the cover...

and if it starts to hop, stop!

 

[black03_cobra]

rev around 3500 and slip the **** out of the clutch you wanna race you will break just get use to it.

 

[Tractionless1]

IRS w/steeda brace, IRS subframe plates, and Maximum bushings (3). Fidanza 4.3 clutch, CF driveshaft. Launched at 3.5k, 4k, and 5k on 16x11.5 slicks without issue, fast slip.

 

[josh2016]

how are these guys running 9's on the IRS without breaking it??

 

[Senkak]

I used to launch on slicks and spray with no breakage. The car has been raced since 2005.
Slicks help to absorb the shock of launching.
Definitely get the brace. The stock diff cover is thin, weak and prone to breakage.
Go have fun and don't worry.
Why do you want a solid especially if you don't race much?

 

[josh2016]

the reason i dont race much is because im worried about breaking my IRS lol. so i should be good dumping the clutch at 3500 with a drag radial at around 12 psi in the tires??

 

[DarkMach1]

I take it you'll be going to PBIR? Well, as long as you brace it, add a bushing kit and get some weight transfer going to the back you will be ok. Make sure you really heat up those drag radials with a 2nd gear burnout and if it hops, let off, its not worth staying on it.

 

[black03_cobra]

NIKE. just do it

 

[fire_4_effect]

whatever he just said... LOL!

 

[josh2016]

I take it you'll be going to PBIR? Well, as long as you brace it, add a bushing kit and get some weight transfer going to the back you will be ok. Make sure you really heat up those drag radials with a 2nd gear burnout and if it hops, let off, its not worth staying on it.

yes im taking it to PBIR. im going on wednesday. if u live around here u should go. why should i let off if i start getting wheel hop?

 

[85FourEyedGT]

dont be scared! ive done 5k quick slips on 28x10 slicks with no problems , slicks actually prevent breakage because the absorb the shock, i would be very careful on drag radials although I once did it when i had radials, 3500 rpm and a quick slip from the clutch and youll probly be ok, if it hops, get off, other than that, dont fear the IRS!!

 

[DarkMach1]

yes im taking it to PBIR. im going on wednesday. if u live around here u should go. why should i let off if i start getting wheel hop?

I live in Miami, but I wont be able to make it because I get out kinda late to make that drive. You gotta let off to prevent rear end damage(snapping halfshafts).

 

[Tractionless1]

the reason i dont race much is because im worried about breaking my IRS lol. so i should be good dumping the clutch at 3500 with a drag radial at around 12 psi in the tires??

NOOOOOOOOOO the consensus is fast SLIP


I live in PSL as well the info. supplied above was done at PBIR. Be careful on drag radials though much more prone to hop. I'm using bias ply tubed slicks and the car damn near drove itself.

3500 or even lower should be a good start point with 4.10s which IMO are overkill. I've seen alot of post about "idle lanuches" give one of them a try, IE like a standing street start from a light. I spun through 1st at the track with my slick setup at 11 psi and the 3.55's. I'll never lower the gearing thing is a tq. monster as it is why make traction even harder to achieve?

 

[Senkak]

NOOOOOOOOOO the consensus is fast SLIP


I live in PSL as well the info. supplied above was done at PBIR. Be careful on drag radials though much more prone to hop. I'm using bias ply tubed slicks and the car damn near drove itself.

3500 or even lower should be a good start point with 4.10s which IMO are overkill. I've seen alot of post about "idle lanuches" give one of them a try, IE like a standing street start from a light. I spun through 1st at the track with my slick setup at 11 psi and the 3.55's. I'll never lower the gearing thing is a tq. monster as it is why make traction even harder to achieve?

I let the clutch out so fast my knee almost hits my chest and I have never broken a half shaft.
Bias ply tires are much easier on the drive train.

 

[josh2016]

wow i never thought slicks would be safer since they are so much stickier. i thought the sudden jolt of torque is what snapped half shafts. i get wheel hop on the street all the time without letting out of it. why is it different on the track?

 

[Senkak]

Wheel hop breaks half shafts.
NEVER drive through it.
Consider yourself lucky you haven't broken one yet.

 

[ttk53]

get some et streets or slicks DR's are what brake parts. oh and a IRS brace.