casual, thanks for the hands- on approach, I will send you messages as I'm going through this project but here are my thoughts on what you said so far. I have many theories in my head but zero experience with forced induction , so appreciate the insight
- Why an air to water? I was just "theoretically " considering that water has more than 10 times the heat absorption capacity of air, but honestly I tend to trust experience and try to match it with the theory later. I tend to agree on the air to air inter-cooler. I was actually thinking of measuring my intake temp now and taking it as a base line. I'm sure its very hot.
- I'm very interested on the meth injection piece.
But couple of things, my stock 2000 4.0 injectors are 21.5lb/hr not 18lb .they run at around 49-45psi rail pressure that is not adjustable as there is no fuel return line. The regulator is integrated with the pump in the tank. The stock injectors are capable of running at 11 afr ( AEM wide band gauge ) near the redline. I also got a spare set of hesco 24 lb/hr ones. I have no problem running meth except where to source meth itself
. I live in egypt so i need to figure out how to source it from an industrial application or something, it wont be readily available for automotive use. maybe you can help what is the chemical name / grade of meth? and where exactly is it injected in the intake manifold?
- The biggest problem with the 2000 factory ECU is the following.Running at a very lean 14.5 to 15.5 afr below 2500 rpm and at ALL part throttle modes. I have to FLOOR it to get the afr jumping after some hesitation to a steady 13 then 12 then 11 near the redline.
The main function which I need from the piggyback or any fuel computer is OVERRIDING the stupid two oxygen sensors input without tripping the ECU. They seem to interfere very heavily in the fueling that I cant even use the simple tricks like adjusting the MAP sensor voltage to go a little rich . The ECU will just cut it back again. If I can override the their signal or plug in a simulator or whatever and design a fuel return line to the tank with a rising rate fuel pressure regulator shouldn't this do the job?
Love to hear ideas on this.
- I love the AEM v2 but I just cant afford it
, I might even not be able to afford the AEM FIC with the patch extension harness thats specific to jeeps, nearly 600$
. there is one specific version for mopar ECU's a well ,however I'm interested in the miscellaneous items you mentioned. I will contact you separately. but I need you experience with turbos
- I am actually starting to hit a dead end with the supercharger packaging under the hood, my prime option , the eaton M90 just wont fit under the cherokee hood with an intercooler, and i'm not doing any scoops or cuts there. And i just cant find a centrifugal blower ( vortech, paxton, etc ) under 2000$ , they are very rare used as well, I actually started shifting my thoughts to a turbo charger .
- Question for the turbo experts: why does the turbo have to be at the exhaust manifold area, what happens if ( due to space limitation ) I go downstream of the down pipe, reroute the exhaust and mount the turbo under the car somewhere at the other side of the engine bay. I know it sounds silly, but it should work.
- what do you think of my flow calculations : assuming 75% to 80% VE at 5200 rpm the 4.0 flows 273 CFM, multiply that by a pressure ratio of 1.5 and I have around 410 CFM at 8 psi . around 28-30 lb/min . matching that to various compressor maps I found the
Turbonetics T04E54 Trim matching perfectly at an efficiency of 74% at maximum flow. any good sources for such a turbo used or an one equivalent to it? I'm targeting to find a good used one for around 500$.
- what does control maximum boost, is it the waste-gate setting or the blow off valve? from what I know the purpose of the blow off is just to vent when the throttle is shut under boost.
- Where do you usually connect the oil supply line to the turbo, I know the drain goes in the oil pan, but where does the in-feed come from?
- what are typical intake air temps as they're coming out of a turbo at 8 psi , just to get a feeling,180 F ? higher, lower?
hope to hear some thoughts!!
