CMC legal coil question

[MHISSTC]

Sounds like it might be a MAF issue. I've had them go bad on the dyno and had the MAF end up being the culprit.

We're running speed density with no MAF.

[MHISSTC]

What about putting a volt meter on the TPS to make sure it's ramping correctly during tip-in.

That was also my initial thought, but it checked out when we had looked into it previously. It's also in intermittent problem that went away when Dave was moving around the wiring harness, so we're still inclined to believe it's something pertaining to either the loose male connector on the coil and/or the crappy old brittle wiring in the harness at the connector to the coil and at the SPOUT connector. Our plan is to replace the coil (the reason this thread originated), along with the coil connector and SPOUT connector portions of the harness with available OEM replacement connectors and pigtails.

[MHISSTC]

I thought you were using Cobra engine management? If not what kind of fuel pressure do you run? Was there a time when you didn't have the tip in hesitation?

Basically it's a '93 Cobra engine running on what I believe is an '88 speed density computer. Without looking at Dave's documentation, I can't specifically say what our max fuel pressure is, but I want to say 34psi at WOT.

[BADVENM]

Fuel pressure is in the 40-44 psi range.

[MHISSTC]

I think Mike is spot on in everything he has said. OE parts is not a goal, rather a tactic to achieve a goal of cars being safe, cheap, reliable, and good for competition. Sometimes OE wins, sometimes it doesn't. However, I do recognize that when the ignition rule was created, all aftermarket ignition coils, distributors, bla bla bla were more expensive than boring looking black OE replacements. If that is no longer the case and therefore the balance shifts...great, lets get the facts together using real data across the platforms and change the rules.

Yes, probably a good time for a review.

I've been researching this heavily over the past few days. Condensing everything down... ...and with zero ability to control timing from a fancy distributor and with our engines at the level of performance they operate... ...it seems the only "performance" benefit to be had from a hotter coil (higher voltage output) is possibly a smoother idle. Basically, it seems if you don't have super high compression, or power adder, or super high RPMs, there is actually no "performance" advantage to be seen. The only potential advantage may be with better longevity and durability if the manufacturer uses higher quality components. And from what folks have already posted, that may also be questionable. If the quality is the same, the benefit may then only be a cheaper price than the OEM brand, as the OEM brand (Motorcraft/Autolite in our specific case) seems to now have a higher price tag attached to it, even though it may only be a rebranded part from a specific no-name manufacturer.

And now I'm even seeing other threads that claim the aluminum terminals on caps may actually have a performance advantage because the conduct electricity better than brass. If that's the case, the only benefit to brass is possibility they wear better/oxidize differently than aluminum.

[MHISSTC]

Fuel pressure is in the 40-44 psi range.

My dyslexia must have kicked in. I guess the number should have been 43.

[marshall_mosty]

What about the salt/pepper shaker plugs that merge the main computer wiring with the EFI harness? Maybe time to cut them out and solder all that back together?

How do your grounds look? Do you still have the ground strap on the back of the driver's side cylinder head?

[Supercharged111]

Fuel pressure is in the 40-44 psi range.

My dyslexia must have kicked in. I guess the number should have been 43.

We can rule that out. I tell you what, my car is chugging when I leave a sweeper like I'm out of gas. How about you leave your car broken for HPR so we're even?

[BADVENM]

We've got the CMC title for 2017 so we dont need to show up and run. If we do show up its only to make sure our electrical fixes are good on track and no other issues arise. I'm not risking any physical contact with any other cars (cough) since the day after HPR we start heading to California for Nationals.

[BADVENM]

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