I also have an 04. I essentially killed the trace on the Jeeps PCB and wired the GM CEL into the trace.
What all should I do before adding a supercharger or turbo?
- Thread starter Torqythewrangler
- Start date
I also have an 04. I essentially killed the trace on the Jeeps PCB and wired the GM CEL into the trace.
Longhorn84
TJ Enthusiast
Longhorn84
TJ Enthusiast
What about trying to max out the naturally aspirated route? https://www.roadandtrack.com/car-culture/a34098448/straight-six-jeep-engine-400-hp-dyno-video/
Then add forced induction.
$30K later, you can have 500-600 hp at 5,000+ RPM.That Newcomer engine is actually impressive, but I have no idea where it could actually be used, as most people aren't racing Jeeps in super stock classes.
Interesting. 29 comments and only 1 mentions "- engine compression numbers look good"
unless you are replacing the motor, the first thing you should check is compression. If the motor compression is weak now, it will be non-existent after adding a turbo or blower.
unless you are replacing the motor, the first thing you should check is compression. If the motor compression is weak now, it will be non-existent after adding a turbo or blower.
The OP hasn't been on this forum since starting this thread with his first and only post.
Now I'm curious your exact question.
I think the general thought is that bad/low compressions numbers indicate an existing issue that would be blown out by the additional heat/pressure and stresses from forced induction. I.E. if the rings are already worn and weak, they might not hold up long due to the increased heat and pressure.
Now I'm curious your exact question.
I think the general thought is that bad/low compressions numbers indicate an existing issue that would be blown out by the additional heat/pressure and stresses from forced induction. I.E. if the rings are already worn and weak, they might not hold up long due to the increased heat and pressure.
Some of the strongest running boosted engines are the most worn out in my experience. Super tight engines don't like the added heat and pressure that boost brings with it. Obviously if you have a leaking headgasket it's not going to last, but a little extra ring clearance isn't going to hurt.
bbaldwin237
TJ Enthusiast
That was my thought this morning. Maybe an old banned user that squeaked by Chris and thought they would pull the pin and toss a grenade.
Rings are designed to operate at a certain pressure. As they wear out, your get blowby. Increase the pressure and the blowby worsens. That blowby increases crankcase pressure. If you increase the pressure in the cylinder on a weak engine, you automatically increase the pressure in the crankcase. Where do you think that goes? A very mild boost isn't bad but then that doesn't yield much HP gain.
If what you say is true, then all the drag racers would use worn out motors. They don't. The Top Fuel guys rebuild their motor after each run.
Then why do engine builders run more ring end gap with forced induction? The blowby on even the most worn out of engines is easy handled by a good crankcase vent or catch can. Top fuel is apples and oranges. Those guys have no choice but to rebuild after each race as they're in detonation at the 330.
because the engines heat up faster and the rings expand accordingly. At design temp, there is no ring blowby. The pistons and rings are balanced for the boost. Blowby is lost power.
The rings expand more on a turbo engine because of the additional heat and pressure when in boost. Driving around the rest of the time the cylinder temps are the same as stock. That extra gap causes blowby. An argument can actually be made that the added cylinder heat from boost could actually reduce blowby on a worn engine by expanding the worn pistons and rings closer to their original size. It would be an interesting experiment.