Right now I'm using my RS as my daily driver. It has a bottom end knock and although I have done the mods listed in my sig as well as rebuilt the TBI unit and replaced ALL sensors my car still doesn't run perfect. It will slightly bog in any gear after 3,000 RPM and yes my timing is set perfect. Anyway, it does its job, runs OK, and gets me 24 MPG averaging 75mph highway. I have an '05 GTO for my recreational baby, but I really want to help this Camaro out. I have an LT1 cam and am thinking about the World SR Torquer heads. Anyone know what kind of gas mileage I would see with this combo?

 

I wouldn't put too much money into a motor with a knock, they usually don't last too long once you get a true rod knock. Also keep in mind that this knock is probably tripping your knock sensor, which is probably where your bog is coming from. I would do some datalogging and see what the ECM is coming up with.

I don't know what kind of milage you can expect, but it will probably go down hill quick if you don't do any kind of diy chip tuning. With tuning, I don't think low mid 20's are out of the question. A lot will depend on your gears.

 

Thanks for the reply. My car only has 84K original miles on it. The knock it has is only noticable at idle, and both mechanics I've had look at it say it could be a rod, bearing, or something else. I would like to keep this car for my daily driver. I've been driving it daily 44 miles one-way to work since March of this year. The knock has not gotten worse and overall the motor runs well. The stumbling in the upper RPM could be due to the knock sensor messing with timing, but I thought a rod/bearing knock would not set it off? Anyway, I might just get it rebuilt if the knock starts getting worse.

 

It all kinda depends, knock sensors are tuned to pick up a certain frequency. Your knock might be getting to the point that it's the right frequency. It just accured to me what your problem might be. We have an old s-10 with a 4.3 it developed a death knock and we drove it another 20000 miles anyway just because it was only used for short trips. When I would datalog, it would show everything was fine. Once the knock got worse it finally started tripping the sensor. We tore it down thinking it was a rod, ended up being piston slap. The bore had wore enough on the top end that it let the piston rock back and forth in the bore making a nasty knocking sound, that really didn't effect the way the engine ran.

I hate to suggest this, but you might try unhooking the sensor, if it helps you can get a resistor to replace the sensor, and it won't throw a code. This might get you a few more miles out of it before a rebuild.