Alright I have a 2002 escalade AWD have a 6.0L with a paxton 1200 supercharger. I fried one of the pistons and scored the cylinder wall. I need some advice on what I should do. Im kinda on a tight budget so i dont want to go crazy. I want it to be reliable also. Im planning on putting the supercharger back on. Any ideas would be great.

 

Well you can always try and put a piston back in it. That would probably be the cheapest way. However, you probably need to look over the combo and tone it down a bit to keep this from happening again. If you wanted to go aftermarket, you could always put forged rods and pistons in your block or go with a complete short-block. We have a 408c.i. short-block in our engine special that would work great for you. It has -10cc pistons which should put you just under 10:1 compression. Right now it is $3800 SHIPPED!

Jon

 

I would just buy another shortblock. 6.0L shortblocks are cheap from junk yards these days. Save you a lot of hassle changing pistons.

BTW How is the 4L65 holding up? I've considered a Procharger for my '05 EXT.

 

By fried do you mean melt? Did the piston break a ringland? When you say it scored the bore did it just get it hot and discolor it? Or did it cut it? There are people on this board making a lot of power on stock LQ4's and 9's.

If I'm not mistaken all the Escalades come with the LQ9 motors. The only difference between the LQ9 and the LQ4 is the compression ratio. This is different because the pistons are different.

I'm curious as to how much boost you were trying to run on the high compression version of this motor with stock pistons. Did you change the injectors? Or did they sell you a full pressure booster thing? Was it tuned?

I've got a lot of questions here before I can give you what I consider a solid answer.

If you've already spent the money on tuning and fuel modifications I would do one of several things:

#1: I'd find another LQ9 in a junkyard and drop it in. Have the truck retuned and make sure you're running on the rich side. You've got no room for forgiveness with factory pistons.

#2: Budget willing, I'd take a look at my old block and see what kind of damage was done. If you could get away with having it honed or taken .030 over you may want to look into that. You'll be reusing your stock crankshaft and find some cheap eagle H-Beam rods to put on some dished pistons sized accordingly to your new bore size. New Bearings, Gaskets, Machine work, Rods, Pistons. This is obviously the more expensive route but it's also the route that's going to keep you from having to do this again.

If somebody just sold you this kit and a fuel pressure booster and told you everything would be fine I would do one of several things:

#1. I'd go to a junkyard and find a LQ4 motor. The reason I say this is because they're lower compression and if you haven't put the money into the supporting modifications you're better off running something that's less likely to blow up.
#2. I'd lick my wounds and find a junkyard motor for it. Take the supercharger off until you're ready to do it up right. You're just going to keep throwing motors at this thing if your tuner can't get the fuel trimmed out correctly.


There's also the possibility that a ringland decided to let go, which is normally due to detonation... Depending on how bad it ate up the bore and if it made it on top of the piston there's a possibility it ruined the head.

The bottom line here is I need more information before I can help you decide what the best route to take would be.

 

The motor was tuned with the supercharger and it has bigger fuel injectors also. Im pretty sure it ignited some how. The tip of the sparkplug in cylinder 5 was broken off. I havnt got a chance to pull the motor yet and see what excact damage was done. Im just trying to get some ideas so I know what to do when it comes to it. I should have the motor out and apart by next week.

 

I could do without the 4L65 I have a feeling its going to be the next thing replaced and I only have 42kmiles on the truck