Recent content by hexdmy

It's important to think of the tune or “tuning” as not a way to squeeze every last hp, but to make sure the vehicle will run well and stay running well. I find that people think a "tune" will fix everything, however I typically spend as much time, if not more time, diagnosing and repairing...

This engine was not as knock prone as many Jeep stroker engines tend to be. If it was, I would have backed off the timing a bit more to leave some extra margin. Final timing values were not much more than stock, that’s all this engine needs. I've worked with other stroker engines that even on...

Just a reminder as to why you need to watch your fuel pressure. This truck had no delivery issues with the stock engine, but once the bigger injectors were installed with the stroker build, the pressure started falling off excessively.

Unfortunately the only way to really know is to run a few combinations both on an engine dyno and on the hub dyno.

Here is the dyno data to review, I've included delta hp/tq data as well as some ecu data: intake air temp, coolant temp, injector pulse width, injector duty cycle, vss, measured lambda, commanded lambda, manifold pressure. I tried to keep coolant and intake air temperatures consistent run to...

Yes, this is Chris.

Just a couple of comments, and I understand that many know these points already, but I just thought I would chime in based on my experiences tuning these motors. Fuel tuning: Strokers need bigger injectors, roughly in proportion to the increase in displacement. I typically recommend 27 lb/hr...

I believe that when people ask questions, especially ones that requires some thought, that they should put in at least as much effort as those who my be offering some help or advice. Half of this thread has been spent trying to get all the details out of this guy. If he had just put some effort...

You did not specify in your post if you are running a factory or aftermarket ECU, assuming you're running a factory ECU it should be running in close loop unless you're nearly at full throttle in which case it would taper into a power enrichment mode. And the ECU does not hold the engine at...

I think anyone who would be capable of answering a question along those lines would be hesitant about answering it seeing as you have put zero effort/thought into asking the question.

You need to check cranking voltage at the starter and the battery. Volt meters are cheap if you don't have one. Check voltage while cranking directly at the battery, should flutter around 10 volts, if you are down in the single digits, and the battery is fully charged, it is likely you have a...

If you paid a shop to diagnose the problem, and they diagnosed it incorrectly, then take it back or get your money back. Any legitimate repair shop will accommodate you. Curious to know what shop you took it to as I am in the la area as well. I would ask also, did they apply vacuum to the...

Did you check to see if the injectors are dripping as someone mentioned earlier? I would take the rail out with the injectors while the engine is hot (be careful) and watch for drips. You really should have no drain back to the tank, the pressure drops normally as a result of the fuel cooling...

So one of the points of the video is that you don't need the scan tool to do a minimum air flow test. You should see a rpm drop but the engine should still idle. The heads up data was shown to help the viewer "see" what the Ecu was doing.

You can check injector by swapping to another cylinder and seeing if the misfire follows. Also have you done a minimum air flow test as illustrated in the link below? If you do and your RPMS are near normal idle speed you have a vacuum leak possibly at cylinder 1 as other have suggested...