5-Tec mods by J5 are a dumb idea

Since its was a locked thread with no replies allowed, i just had a few questions. Now if the ignitor is under the intake, behind the power steering assembly and the AC compressor (on some 2.6L it was an option), wouldn't the amount of air flow be greatly reduced especially with those blockages and reduce the cooling over the fins? I know the internal "tar" tends to leak out of these over time and that would be considered due to excessive heat. Secondly, all the heat blows back from the radiator fan, off the radiator over the block and head and the back of the block causing the firewall to get the hottest. As well as the right side with the exhaust manifold adding to that heat. Old school mechanics always said the back cylinders get the hottest due this...As wouldn't the coil being mounted at the rear of the valve cover also be a bad location for something that is effected by high temps as stated? as much as i know MANY people dislike John on this and other forums, i am neither friend nor foe of his and just ask these as simple questions to further support or disagree with ones facts and/or opinions. Being the ignitor is up in the airflow, again i mention the 6.5L chevy diesel relocation as the airflow improvement is its mounted up high in the engine bay (on some mods, some are in the grill) and in the front of the engine, like the J5 mod. again, not ruffling feathers, just simple questions for a (Prior locked) thread that these questions i could not ask.

on a side note: I have been building/rebuilding/customizing Isuzus since 1991. I have run Jacobs ignition systems and others engine modifications off the 2.3 and 2.6 to eliminate some of their known flaws and tossed out the emissions injection systems all together and left just the cat with 50k miles without issue on my old 2.3L pickup and had over 300k on an 1985 P'uP 1.9L 4 speed Long bed that had its smog pump belt removed around 100k. I have passed NJ tailpipe/dyno emissions test up until a few years ago, when they ditched anything pre OBD2 for inspection, even safety was dropped...gotta love politicians and the cost of spending money..... my old 1994 Pickup w/2.3L and a weber, it ran cleaner than my stock 2.6L 1990 Spacecab. the 2.6L always had MUCH high NOx numbers compared to the Weber, and often the 2.6L failed for that unless i ran the tank low and ran alcohol in the system as well as mess with the timing to pass.


if you ask about passing NJ inspection and a Weber, a blank CEL (w/ truck off and key on OR while running) was an instant fail, so on the 94 i prevented conductivity to the CEL circuit on the cluster and wired the bulb socket tabs to the oil pressure bulb socket on the cluster so when it was keyed on to check the CEL was functioning and when it started and built oil pressure, both the CEL and Oil Pressure lights went out.....and i passed that part of the test
just asking
Ron

conversation is welcome.
Personally I have never had any issues with J5. I also only spoke to him one time.

There are a few different beliefs that people have about engine bay air flow.
I have never talked to someone about this subject that didn't consider radiator location, low pressure and air volcity.

If you draw a level line from the igniter to the front of the vehicles you will notice the igniter is located in a direct line with the lower 1/3 of the radiator & directly in-between the power steering pump. The intake manifold is large and over hangs the igniter by quite a distance. Under the vehicles behind the front axle is a huge low pressure area.
The temperature of any vertical flow radiator is cooler as the flow goes down. This much cooler airflow is directed towards the igniter naturally by its location. while the hotter air flow at the top goes up and over the engine. The intake manifold acts as a shield to keep the hot from above away by directing it out towards the fender. The low pressure under the forward moving vehicle sucks out the air form within the compartment and this add velocity to all the air flow. One law of air flow is that high velocity flow will not change direction easily its is this law that makes the air flow consistently in the correct direction.

The tar like substance ozzing out of any old electronic device from this era is heat sink compound. Its used to thermal couple the MOSFET and the body together. There are 2 reasons why this compound seeps out. 1 reason is because the device has over heated. The #2 reason is simply due to old age. Modern MOSFETS are sensitive to rapid changes in heat. MOSFET from 33 years ago just started to become unusable. Any amount of excessive heat great enough to melt out the compound would certintly result in a failed MOSFET. This is why I am convinced the ozzing is due to old age & nothing more.

itsmehb said:

There is lots to be said about modern fuel injection systems, so why remove them and carb an engine.
To simplify maintaining a vehicle, a carb made sense to

Click to expand...

Harry,
Without serious modifications, most EFI engines would be impossible to convert to carb. For starters, most "newer" ones are distributorless. While you might be able to run the ignition from the ECM, you'd have to figure out a way to fool it about all the inputs. Then there's the "where to put the carb?" Again, most have an intake that is designed to supply AIR to the various cylinders, but not a combustible mixture. When trying to run a combustible mixture through this type manifold, some cylinders end up lean or rich and there can be backfire problems (LPG or CNG conversions). Personally, I played with trying to carb the 3.2 in my 1994 Trooper. I was working on adapting a mechanical / vacuum advance distributor to run off one of the cams (driven by bolt on cam pulley) and was working on a carb adapter / upper plenum. Then I came across the 1991 V-6 Trooper, so the whole project went away.
Other than some of the quirkiness that the 2.6s have, most "modern" EFI is actually pretty dependable. Dennis