kb car goes down !

[back_in_black]

went to a local track for my first run with my 1.7 kb with 10 lb pulley.......1.83 60 ft., 109.9 mph, 12.39 1/4 mile time, smoke started pouring out the exhaust near the end of the run, motor shut down. started motor and I hear a knock, probly, piston rod, time for forged bottom and 14 lb's boost. I am pretty happy with my 1/4 mile time, not to bad for an auto vert !

 

[streetstang03]

at least you get a better motor and the opportunity to up the boost

 

[back_in_black]

yea, I was all ready to go to Ocean City MD next weekend for the hot rod weekend, looks like I'll be driving something else !

 

[RNstanger]

How much power were you putting out with the 10lb pulley?

 

[back_in_black]

it was 397 rwhp through the auto

 

[sgarlic]

Were you shifting past the redline or something? I can't believe you blew it up on your first pass. That's nuts.

 

[mrvax]

Were you shifting past the redline or something? I can't believe you blew it up on your first pass. That's nuts.

Not necessarily. Once you get to near 400rwhp, and through the auto, he's pushing about 496 bhp you are asking for trouble. The rods are the weakest link.


Good luck with the forged bottom end! When I grow up, I want to get blown with a forged bottom also!

 

[Evenflow]

Not necessarily. Once you get to near 400rwhp, and through the auto, he's pushing about 496 bhp you are asking for trouble. The rods are the weakest link.


Good luck with the forged bottom end! When I grow up, I want to get blown with a forged bottom also!

Why wait till you grow up I can blow you right now

 

[back_in_black]

my son filmed the run and you can see a little smoke through the exhaust at the higher rpms in each shift, is this the rings failing under boost ? before this run i had noticed I was also starting to burn a little oil, and had read about mac lt's causing oil blow by, maybe it was signs of rod failure ?

 

[hotmustang331]

Man, thats sad...but KBs seem to have a pretty high failure rate on the stock bottom end. Forge it and crank up the boost LOL, may get 480 RWHP.

 

[Gearbanger 101]

Ahhh one of the mighty KB cars finally bites it when saddled with too much airflow. Maybe this will convince the naysayers that forged internals in a blown car are more of a necessity than they’d like to admit. I’m sure this will be only one of many casualties that occur considering the majority of users that have gotten greedy with the boost.

On a side note, sorry about your car dude , but a built short block will ensure it never happens again.

 

[Gearbanger 101]

The rods are the weakest link.

I disagree. Although the rods do in fact suck, it's the pistons that suck even worse. The problem is that theirs not enough meat around the top ring landing to shield them against even the slightest hint of detonation. The problem being after that, is that once it goes, it tends to take the rod with it.

 

[snGTstang]

that sucks man, im gonna be at ocean city next weekend too. i always like seeing s/c'd mustangs running around.

 

[02LaserRed2V]

Most say 400rwhp is the limit for a stock block.

However, 400rwhp 5-speed and 380rwhp auto = about the same bhp

Many fail to mention that.

Good luck getting everything fixed!

 

[mrvax]

Why wait till you grow up I can blow you right now

Damn homos!

 

[mrvax]

I disagree. Although the rods do in fact suck, it's the pistons that suck even worse. The problem is that theirs not enough meat around the top ring landing to shield them against even the slightest hint of detonation. The problem being after that, is that once it goes, it tends to take the rod with it.

You may be correct. I was basing my opinion on several years of carefully monitoring what blew up on what kind of set-up. I can't tell what 1st happened, only what the end result was.