High Energy Ignition (HEI)

[Ron]

I wanted my PRV to perform at least as well as a 1988 and later PRV, so I upgraded my ignition slightly beyond the same specs Chrysler used on the Premier 3.0.

Let me get this right.
Although you seem to imply it, you don't actually claim it here, so I ask, does this mean you accomplished what it seems you set out to do -- That is, does your PRV meet or exceed the power output and have as clean or cleaner emissions than those of the average, 1988 and later, factory equipped PRV stock vehicles?

[DCUK Martin]

All odd fires, Volvo, Renault, Peugeot have the same setup.

[content22207]

Even fire is where ECU's diverge. Volvo went with a redesigned Bosch ECU for the B280 (still .028" plug gap). Renault/Chrysler went with a Renix (Bendix?) unit for the 3.0 (Autozone shows .044" plug gap, other online sources show .030-.035").

Bill Robertson
#5939

[DCUK Martin]

In the 3 litre turbo PRV, the most powerful production variant (in fact de-tuned so as not the break the trasmission). the plug of choice is the NGK BKUR7ET.

I'll let Bill work out what the "7" in the part number means.

[content22207]

You find the most interesting things in syndicated print:

ClickClackHEI.jpg

Bill Robertson
#5939

[DCUK Martin]

So now I've gone to the effort of enhancing that image so I could read it at all, can you tell me one simple thing:

What's your point?

Modern high compresion, faster revving, higher specific-power engines may require a higher voltage to jump the spark gap, and that gap may, or may not, be wider than 0.7mm

This does not apply to the DeLorean engine whose system works just fine if it's healthy.

[content22207]

Incorrect: higher compression ratios can effectively combust with lower spark energy than lower compression ratios.

As a forced induction user, who publicly claims that his engine runs better with stock ignition than HEI, you should know that.

Bill Robertson
#5939

[DCUK Martin]

Don't go putting words into my mouth, Bill. I said that my turbo engines successfully run with a stock coil whereas attempts to use a higher "performance" unit resulted in misfire. The plugs I use are those used by the Alpine crowd, both of which are cold plugs with a 0.7mm gap.

The voltage required to jump the gap of a spark plug increases with combustion chamber pressure. Prove me wrong.

BTW lets not forget that a few pages back you claimed that inductive ignition has been obsolete since the early 80s...

[content22207]

Prove me wrong.

Pages 61 and 62 of the afore mentioned SAE paper are a good start (are you *EVER* going to read that thing?).

Or, as any student of American automotive history will tell you, as compression ratios dropped from the 1960's into the 1970's, misfiring became an increasing common problem (exacerbated by leaner fuel mixtures). That is one reason American manufacturers adopted HEI across the board in the 1970's.

Don't forget that the DeLorean PRV runs in North American guise (low compression, lean mixture).

Bill Robertson
#5939

[DCUK Martin]

You have AGAIN repeated that the DeLorean engine runs lean. WRONG. The DeLorean engine, as with every engine with a 3-way catalyst, is designed to run at stochiometry (perfect fuel/air ratio) for 99% of the time.

I can't even find the link to that paper now. Please, go ahead and quote the exact passages that back up your assertion.

It is a physical fact that resistivity of a gas increases with pressure. I don't know how you think you can ignore sh!t like this... it is first principles stuff.