ramhunter9
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- Ram Year
- 2012
- Engine
- P-Star Jeep Wrangler
DIY on waste gate inspection
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DIY on waste gate inspection
Good info, are the wastegates know for failure?
Hy35 , no code and I found the issue .. my programer was on #10 setting giving me 45psi in boost . After further review I found non stock injectors and the waste gate works properly .
I don't know what that **** means, but it sounds good!
OK... The HY35 turbo is limited to 30-32 PSI of boost. As for the programmer it will kill off the P0234 error code because of the programmer ability to boost fool. So the ECM never sees above 20 PSI so the error code is never tripped.
Hmmm... I honest suggestion... Upgrade at least to HX35 turbo...
HY35 is a 9cm2 exhaust housing... HX35 is 12cm2 exhaust housing...
So the HX35 will spool a bit later and have more lag but EGT's will be much lower. Might actually see a increase in HP too. Just remember all the P7100 12V's had HX35's on both auto and manual trucks. It was in the 24V trucks that switch the auto's over to HY35 for smog reasons.
Stick around you might learn something... Ask question I'l answer it to the best of my abilities...
please explain the 9cm2 and the 12cm2. the 9 and 12 cetemeter is the opening in the outlet of the turb i believe. what is the 2? maybe a new thread.
So the more air in and more out the better ?
VOLUMETRIC EFFICIENCY AND BACKPRESSURE
Although the turbine recovers wasted exhaust gas energy from the expansion of the hot exhaust gas, the kinetic energy of the flowing exhaust gas and the acoustic energy of the exhaust gas, the working turbine also causes an increase in exhaust gas backpressure. This increase in backpressure can reduce the engine's volumetric efficiency.
A typical, streetable turbo system has more exhaust backpressure than boost pressure and the power gains from such systems are due to the increase in the density of the intake charger, not due to increases in volumetric efficiency. (Volumetric efficiency, if you don't remember, is the volume of intake charge inhaled during the intake stroke vs. the actual displacement of the cylinder. VE is expressed as a percentage; the larger the VE, the better.)
Backpressure is higher than boost pressure because the smaller turbine housings and turbine wheels used to ensure a quick spool-up time also, by nature, restrict the exhaust flow. We will explain the mechanics of this in more detail a little later. Racing turbos, the latest generation of medium-sized turbos and turbochargers for engines where throttle response is not much of an issue (like fixed industrial engines, long haul trucks and aircraft), have free-flowing turbines that have less exhaust pressure than intake pressure. Engines using these turbos often do have improved volumetric efficiency.
This condition, where boost is higher than backpressure, is called crossover and crossover is what ever turbo system designer strives for. In crossover, VE percentages as high as 110 percent are not unheard of. Unfortunately, some of the design features that can create a free-flowing turbo can also contribute to turbo lag, something that is not desirable in a street-driven car that needs a wide dynamic power band.
Excessive backpressure is hard to manage in a boosted four-stroke engine. Excess backpressure causes what is known as reversion. Reversion is when hot exhaust gas gets pumped backwards into the engine during the overlap period. Reversion can cause the engines internals to get excessively hot as cross flow of the cool intake charge during overlap is one of the ways an engine cools its self internally. Hot internal parts can trigger uncontrolled combustion and engine-destroying detonation. Because of this, it is sometimes not a good idea to really crank the boost on an engine that has a small, high-backpressure turbo - in other words, the kind of turbo that usually comes on a factory turbo car. This is a good reason not to go crazy with a boost controller on a factory-equipped turbo car. A little more boost, perhaps 4 to 5 psi might be tolerated, but trying for 20psi could be flirting with disaster.
On small turbo cars with a lot of backpressure, camshaft overlap should be kept to a minimum. This means that the stock cam usually will work best. To deal with the problems associated with backpressure and reversion, the engine's tuning must also be compromised with richer mixtures and more ******** timing than what would normally be optimal for the best power. Even on full race turbocharged cars with low backpressure turbos, camshaft overlap should be several degrees less with more lobe separation angle than on an equivalent naturally aspirated engine, unless physical measurements indicate that the engine is in crossover in the engine's operational range.
Because of backpressure and VE issues, the correct turbo size for the application is very important when designing a turbo system. A small, quick-spooling turbo can be restrictive, causing a great deal of backpressure and reducing VE at higher rpm. This means that small turbos should be limited to lower boost levels. A big, free-flowing turbo can be laggy and unresponsive, making it unpleasant for street driving but producing awesome power at higher rpm.
To combat high backpressure and possible reversion, the compromised tuning needed to prevent destruction with an overboosted small turbo will also reduce power. If a small turbocharger is running backpressure to boost ratio of more than about 1.8:1, a supercharger has a good chance of performing better. Fortunately, it is easy to design a reasonable responsive, powerful turbo system with a ratio of less than this.