RCR: LQ4 Swapped Colorado

[kevm14]

Engine is busted. I can't get to the video at the moment but from what I understand, it went lean and he broke a piston.

The plan is to replace the piston (and whatever else, not sure about the rod) and continue on.

Naturally I like this, because this is the conversation:
"Damn, I busted a piston, this has to come apart."
"Oh really? Was it from having a 288k junkyard engine?"
"No"
"Was it from making 700 rwhp in something that shipped with 250?"
"No, it went lean."

Are fancy forged aftermarket parts more tolerant of this kind of thing? Absolutely. But it still went lean, and going lean can always cause problems, regardless of your build or how much you have into it, particularly with forced induction. Fortunately it's repairable (no spun bearings or rods making a window through the block).

[kevm14]

https://www.youtube.com/watch?v=kMprDr1ziEM

yep all things considered this isnt bad at all, slam a piston in there and clean it all up and keep rockin

Here comes 4g63 guy to diminish the accomplishment:

At least it lasted that long. Not too bad for a stock bottom end

And Matt replies:

well the issue is fueling, soon as that is sorted, nothing broke as a result of horsepower, the issue was lean conditions at very high hp and heat distorted the top of the piston

yeah just lean condition at very high hp on pump fuel and stock piston = ouchie, going to fix this guy and keep pounding, literally over 1000 miles on it already and no issues when the fuel is in it lol

An innocent question from a commenter:

Would an ignition cut at low afr help solve that problem?

And Matt replies:

yep actually my ecu has lean afr shutdown i just wasnt using it!

Ah that's a bummer.

[kevm14]

He was tightening the last torque converter bolt when it stripped.

https://www.youtube.com/watch?v=c9CNqGbtQrk

[kevm14]

Ready for burnouts. On "low" boost only, until he can fix the fuel delivery issue when he gets up to 700 rwhp. So I suppose he's stuck under 500 rwhp. Which is hardly a penalty.

https://www.youtube.com/watch?v=Eqwe977G4cQ

[kevm14]

i only replaced the broken piston and bearings on that cyl just in case they got crushed from the material in the cyl, the rod bearings looked fine but i figured why take a chance, slammed in other used bearings

Used rod bearings!

Someone asks a question about durability:

Are you worried about reliability or longevity with not installing forged pistons, connecting rods or a stronger crank? How long do ls engines generally last and at what boost levels

I suppose it is understandable that people are asking these questions since he did break a piston. But I think his answer clears up what the expectation should be:

not worried about longevity at all in the 600-700hp range so long as there is fuel in there with it!

Here's what I'm thinking:
With 04+ rods (and maybe even with the early ones), if you are careful with air/fuel ratios, engine temp, oil temp and oil pressure, this thing might actually live a long time, even at these power levels. But because he's pushing stock stuff so far, I'd argue the real penalty is that there is little room for error, which was already demonstrated.

[kevm14]

https://m.youtube.com/watch?v=9ziFeQY3KNc

He's starting to make a real case for the MS3 here. Cool shit.

[Bob]

For a second I thought MS3 meant Mazdaspeed 3.

[kevm14]

Whoa, big ass turbo going on the Colorado!!

https://www.youtube.com/watch?v=jsbtJfTdE10

In case you missed it, here's the big-ass turbo: https://www.youtube.com/watch?v=WzSb7jOV0Xc

I love when he talks about how good the drivability is on his Colorado. I really want to drive it. He says it's snappy, which is awesome.

These builds really are impressive compared to what used to be possible. I mean, launching off the foot brake for example. Back in the day you would have had to stage on a trans brake, spool up the turbo(s) and launch just right. These days you can be deep 9s or even 8s off the foot brake. Just crazy.

[kevm14]

He switched his ugly intake pipe for a pretty one. No difference. Similar to what hot rod garage found after seriously denting a set of headers.
https://m.youtube.com/watch?v=pzgPe8FHIoM

Now here he is at the drag strip and more bad luck. Something went wonky with his boost controller. MS3 supports a boost cut which I assume is ignition retard in case of overboost. He hit this a few times then ran an 11.2 on wastegate which is pretty good. I think that is 6 psi. Then he wanted to screw around with something so he shut the boost cut off (fatal mistake) and made a run. Thing topped out the MAP sensor and he estimates it hit 30 psi (data log). Motor is toast.
https://m.youtube.com/watch?v=eSHFBAhDNNk

This allegedly has some good Q/A in a new format:
https://m.youtube.com/watch?v=YFOZmbdYeYw

[kevm14]

This allegedly has some good Q/A in a new format:
https://m.youtube.com/watch?v=YFOZmbdYeYw

This is highly worth watching.