427 engine (part 2) - RHS block - Page 112

Gannet · 11-25-2011, 05:17 PM

Progress.

CorvetteJohn · 11-25-2011, 07:40 PM

You might try switching the coils from one side to the other. If the misfiring cylinder moves to the other side then you will know you have a bad coil or wire. All that this will cost is the time to do it. Just do one at a time that way you will know which one is bad if there is one bad. This reminds me of a time when I had a car all tuned up and picked it up at the garage and started out on a trip. The car would not run over 55 mph so I found a town with an open garage. After a couple of hours on a Sun machine I got desperate and pulled the old coil out of the trunk and re installed it in place of the brand new one. The car ran fine then. Up till then I had always believed the mechanics saying a coil either works or it doesn't. Well I had one that only half worked and I no longer assume new is good.

Gannet · 11-25-2011, 08:27 PM

That's a good suggestion. Those MSD coils are notorious.

**Rich Z** · 11-26-2011, 07:05 PM

Yeah, heard a lot of complaints about these coils. Of course, ONLY after I have LONG had them sitting around waiting for the engine build to get to the point of even putting them on.... Oh well.

I found stock ACDelcos at a decent price, so I've got them on order. But not expecting to see them for a month. I can wait. Got plenty to do in the meantime. Also got some new coil wires on order, since half of the original ones I had when I pulled the car into Harwood's evaporated. These are extremely low resistance wires (like close to ZERO ohms), and I had real good results with them back then.

Still working on getting an wideband AFR setup. I'm probably going to be going with the Innovate MTX-L unit recommended by Bret.

Got some tools and diagnostic equipment on order. Heck, I just LOVE a good excuse to buy tools, so why not? Might be a real good thing for me to get more hands on with this car anyway. Been a long time since I've had a car bark my knuckles and draw blood. And this programming stuff certainly looks challenging and interesting enough to get that sluggish gray matter to firm up a bit.

I'll just be taking it slow and easy and not rushing anything. Not what I had hoped for finally getting my car back home, but it is what it is...

CorvetteJohn · 11-26-2011, 07:16 PM

If my memory is still working I believe you have a Z06 in the garage. You might think about taking the coils from it and trying them on the C5. At least this would give you something to do and perhaps a lot of the bugs you have now with the C5 will disappear. In which case you will know if the coils are causing the rough idle and stumble. If that works then you won't be running around in circles with other stuff. What the heck you can then sit around knowing the real fix is on it's way.

**Rich Z** · 11-26-2011, 07:58 PM

Right now I'm just not trusting my luck enough to mess with the C6 Z06 at all.

Besides, I believe the coil packs are different between C5s and C5s anyway. Seems to me that when I needed to order new valve covers with coil mounts, they needed to know which model it was for because the mounting is different.

Gannet · 11-26-2011, 08:07 PM

You need a wideband? I have a brand new one, in the box. It might even be an Innovate. I'll give you a real good deal on it. Tomorrow I'll go dig around in the garage and see if I can find it.

**Rich Z** · 11-26-2011, 08:09 PM

Oh, and to make something clear that probably was not. I feel I need to buy coil packs and wires, no matter what. I don't trust the MDS coil packs based on all the bad press I have read about them, and the ignition wires now on the car are just some inexpensive truck wires that Aaron put on there because the MSD wires that Harwood put together appeared to be a problem. They were at least a problem in that they did not want to stay attached to the coils. And I'll be quite honest about it, if Harwood had hand made YOUR ignition wires, would you want them on YOUR car? He made those wires from a kit because the original valve covers he put on the car (that had to be replaced because they were too cheap and flimsy) were too tall to accept the stock length ignition wires. So no, they are NOT going back on my car.

**Rich Z** · 11-27-2011, 07:34 PM

Quote:

Originally Posted by Gannet

You need a wideband? I have a brand new one, in the box. It might even be an Innovate. I'll give you a real good deal on it. Tomorrow I'll go dig around in the garage and see if I can find it.

Sure Dave. Great! Let me know what you find.

Lots of stuff going on behind the scenes lately. Been contacted by a guy named Ed Hutchings out of Virginia who is supposed to pretty much the top guy with this stuff. He wants me to go directly to a 2 BAR MAP tune to just bypass the O2s completely. The guy Bret who has been helping me says he is about the best there is.

Going to cost me for another 2 credits from HPTuners, plus the cost of the 2 BAR MAP. And of course Ed wants to be paid for his efforts.

So heck, what do I have to lose? Except my sanity, of course.....

Oh, there is a guy on CorvetteForum who has a set of tested and working coils that he is going to send me for free to help me out. I thought that was darn nice of him. Wouldn't be till the end of December before those coils I ordered from Amazon were supposed to show up.

Do you all really think this is all going to end well? No, seriously......

mickeystoysz16 · 11-27-2011, 08:18 PM

....yes I do. The one absolute certainty is that one way or another it will end! How is the question that leads us on that adventure to find out while hoping for the best.