• Got the Contributing Memberships stuff finally worked out and made up a thread as a sort of "How-To" to help people figure out how to participate. So if you need help figuring it out, here's the thread you need to take a look at -> http://www.corvetteflorida.com/forums/showthread.php?t=3581 Thank you, everyone! Rich Z.

427 engine (part 2) - RHS block

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.

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.

Hello Rich,

Did you ever check with Masport I mentionned to you on 07-10-2011...he is in Florida...

Dan Maslic is the tuner behind my powerful NA daily driver...and I haven't been ever more satisfied of a tune and the behavior of the engine!

His knowledge is not questionable as he is the author of the "MASTER EFI TUNER-GM EFI Learn How to Tune GM EFI" book published by Embex Group.

Dan Mastic is as well the one tuning the Mosler's, all of them, from the engine dyno at totalengineconcepts with Mike in Riviera Beach to the finished rolling projects on his Mustang dyno in his Boca Raton workshop...

Christian
 
Actually, no, I did not. Ed contacted me when I posted some queries over on the HPTuners forums. He seems to be willing to take a stab at this remotely. Boca Raton is quite a distance from Talllahassee, and I'm not looking to drive my car any distance (simply because I won't trust it to be reliable for quite a while) to have someone else work on it. From all accounts I have been able to locate on the web, Ed Hutchings is claimed by many to be THE guru in this sort of stuff. So we'll just have to see....

In any event, I uploaded the latest scan video I took this past Friday when Bret was logged into my laptop and doing some tuning changes real time. The graph plainly shows some problems with the O2 sensors, which is the last group of graphed lines. You may need to actually view this at full screen with the 1080 resolution to read the labels.

 
As a comparison with the above, I looked at another scanner log file that I took back in 2006 with the LS6 motor to see what the O2 sensor readings looked like. As you can see, there is quite a bit of difference. At least in my newbie opinion of such things...

 
I was climbing around underneath the car yesterday looking for obvious problems with the O2s that might be giving the readings we are seeing.

Except for an obvious cable splice job, nothing leaped out at me... :rolleyes:

o2_01.jpg


o2_02.jpg
 
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While underneath the car, I also looked around for anything else that might seem odd. Well, the cats have been relocated to being in back of the crossover pipe. Is that normal?

cats_01.jpg


cats_02.jpg
 
I love the trailer wiring harness / O2 extension cable I assume Harwood did....

I have to ask but are there just 2 O2 sensors or 4 O2 sensors on your car?
 
I love the trailer wiring harness / O2 extension cable I assume Harwood did....

I have to ask but are there just 2 O2 sensors or 4 O2 sensors on your car?

There are only two O2 sensors. The rear two bungs (which are on the crossover pipe now in front of the cats), are plugged off.

Actually that cable has been spliced TWICE. Once near the sensor, and another time up near the connector.
 
Well, I've been talking to Ed Hutchings about doing this new tune with a 2 BAR MAP sensor. The drawback is that the standard 1 BAR MAP sensor needs to be replaced with the 2 BAR unit. And that sensor is located in BACK of the intake manifold. Ed asked me if I have small hands, and yes I do... But, but, but well, just HOW small do my hands have to be to reach around there?

manifold_back_01.jpg


manifold_back_02.jpg


I tried to put my hands into those available spaces, and the best I can do is to get my hands up to my knuckles wedged in. Which gives me enough room to, at best, merely wiggle my fingers futilely at anything back there. :confused: I think I would need tentacles, rather than small hands with fingers for that job.

:banghead:
 
Well, I've been talking to Ed Hutchings about doing this new tune with a 2 BAR MAP sensor. The drawback is that the standard 1 BAR MAP sensor needs to be replaced with the 2 BAR unit. And that sensor is located in BACK of the intake manifold. Ed asked me if I have small hands, and yes I do... But, but, but well, just HOW small do my hands have to be to reach around there?

manifold_back_01.jpg


manifold_back_02.jpg


I tried to put my hands into those available spaces, and the best I can do is to get my hands up to my knuckles wedged in. Which gives me enough room to, at best, merely wiggle my fingers futilely at anything back there. :confused: I think I would need tentacles, rather than small hands with fingers for that job.

:banghead:

In almost certainty you will need to remove the intake manifold to replace the MAP sensor. Unless your SO can get their hands back there to perform the work. And if anyone has put RTV silicone on it to hold it in place, it will be even harder to remove.
 
In almost certainty you will need to remove the intake manifold to replace the MAP sensor. Unless your SO can get their hands back there to perform the work. And if anyone has put RTV silicone on it to hold it in place, it will be even harder to remove.

No, Connie's hands won't fit back there neither. She tried....

Heck, I've pulled off the intake manifold of my '66 GTO back in the old days MANY times, but that was a piece of cake. Nowhere near all the stuff on an engine like there is these days. But if it's what I've got to do, then I don't see any other options presenting themselves to me. I guess getting over being a virgin at anything is a bit intimidating. I suppose the old argument of "well you either do it the first time sooner or later, or you never do it at all" applies here as well. :hehehe:

I mean, after all that has happened so far, what's the worse that could happen now?

Oh yeah, I know. I swear I smell a gasoline leak somewhere on that car. But I've looked everywhere and can't see anything leaking. I guess when I disconnect the battery and it throws a spark I'll find out where the leak is.

So here's a question. SHOULD the fuel system hold pressure after the ignition is turned off? If not, how does the pressure get bled off?
 
I believe that you pull the fuel pump fuse and wait for the engine to die. That gets
rid of most, if not all, fuel pressure. Removing the intake manifold is daunting at first,
but after you see how its done, and watch one being done, it seems to all come
together. I watched mine being done when I had the oil pressure sender replaced,
and I think I will be doing it the next time it needs done. 2 things to keep in mind.......
1. use masking tape to cover the intake "holes" in the head after the manifold
is removed to keep "stuff" out of there.
2. replace the o-rings that seal the intake passages before you reinstall the manifold.
they don't cost that much, and you damn sure don't want to be going back in there
to do it after you've got it all buttoned up again.

Andy Anderson :wavey:
 
I believe that you pull the fuel pump fuse and wait for the engine to die. That gets
rid of most, if not all, fuel pressure. Removing the intake manifold is daunting at first,
but after you see how its done, and watch one being done, it seems to all come
together. I watched mine being done when I had the oil pressure sender replaced,
and I think I will be doing it the next time it needs done. 2 things to keep in mind.......
1. use masking tape to cover the intake "holes" in the head after the manifold
is removed to keep "stuff" out of there.
2. replace the o-rings that seal the intake passages before you reinstall the manifold.
they don't cost that much, and you damn sure don't want to be going back in there
to do it after you've got it all buttoned up again.

Andy Anderson :wavey:

That Aeromotive fuel pump doesn't seem to hold the fuel pressure indefinitely after I shut the car down. So that is my question: What is it that bleeds off the pressure? If there is a small leak, that might explain it. And it might be small enough that the gasoline evaporates before it can actually leak somewhere that it will be noticeable. But fact of the matter is, it's a fire hazard if that is the case, and although it wouldn't surprise me in the least if this all ends in this manner, I'd really rather that it not.
 
Since you have a lift you might look from the bottom side to see if there is room to get to it from there.

Yeah, I looked at it from that angle. Not a chance......

Ed tells me that all I need to do is to get the cable end off of the sensor. We can relocate the new MAP sensor up front somewhere. If I can get that fuel rail off on the passenger side, I think I can get to it from there. But never taken a fuel rail off before... :shrug01:
 
That Aeromotive fuel pump doesn't seem to hold the fuel pressure indefinitely after I shut the car down. So that is my question: What is it that bleeds off the pressure? If there is a small leak, that might explain it. And it might be small enough that the gasoline evaporates before it can actually leak somewhere that it will be noticeable. But fact of the matter is, it's a fire hazard if that is the case, and although it wouldn't surprise me in the least if this all ends in this manner, I'd really rather that it not.

My guess, and it's only that, is that it bleeds back through the pump. If you don't see or smell fuel, you almost certainly don't have a leak.

[EDIT] I see now where you said you smell fuel. Nevermind...
 
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Yeah, I looked at it from that angle. Not a chance......

Ed tells me that all I need to do is to get the cable end off of the sensor. We can relocate the new MAP sensor up front somewhere. If I can get that fuel rail off on the passenger side, I think I can get to it from there. But never taken a fuel rail off before... :shrug01:

Relocating the MAP sensor is pretty common with FAST manifolds. LPE makes a block-off kit for the hole, and Katech and LPE sell extension harnesses to move it forward. If you search on "FAST MAP relocation" you'll find threads with pics.

This one has some good step-by-step pics of the manifold removal and relocation install about 3/4 of the way down-thread.
 
Relocating the MAP sensor is pretty common with FAST manifolds. LPE makes a block-off kit for the hole, and Katech and LPE sell extension harnesses to move it forward. If you search on "FAST MAP relocation" you'll find threads with pics.

This one has some good step-by-step pics of the manifold removal and relocation install about 3/4 of the way down-thread.

Yeah, I saw the writeup when I was looking to see what the heck I would be getting into with this MAP relocate. I'm not sure what Ed has in mind, because Aaron hooked into that place on the intake manifold he was looking to use with the vacuum line going to the boost blow off valve. I guess what is worrying me is that with stuff like this, although it's not all that tough, if you haven't done it before, nearly all the little parts you need you won't know about till you get there, and that means running to the store to buy a 50 cent item and burning $10 in gasoline for each trip. That's even if the local stores have what you need, which if history has been any guide for me, is rarely the case.

Heck, I dunno. I did my share of wrenching when I was younger, but gave it up out of frustration with wrong parts, DOA parts, parts that ALMOST fit, and crap like that. I'm not sure I want to do that sort of thing again. But on the other hand, after taking that big hit on the bill from Aaron, finances may not allow me to just send the car off to someone else to finish it up. I certainly can't bankrupt the retirement fund for this car.

So, quite honestly, I may just hit a brick wall with this...
 
Went out to the garage today to try to locate a fuel leak. Getting tired of the smell of gasoline when I walk in there. Already had the car on the lift, but first decided to just look under the hood after pressurizing the fuel lines. Yeah, saw some wetness on an injector just below the fuel rail. Connie was helping, and she suggested running the car and checking it again. So yeah, the injector on cylinder #6 is leaking pretty badly where it joins with the fuel rail. Not a gusher, but the injector looks all wet with the engine running. Well, I guess I have dodged Murphy's Law (so far) on that one. Apparently his plan was for me to become a fireball rolling down the road on my way home from Aaron's shop. So I guess even Mr. Murphy is subject to Murphy's Law sometimes.
 
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I talked to Aaron about this and he suggested just trying to move the injector to see if it will seal at the fuel rail. Just about everything is new in this car, so it just might be a seating issue that manifested itself during the drive home. If not, he will send me some new seals, which would mean I would be pulling off the fuel rail. Not sure how well that will go if the fuel system is still pressurized, so I'll let it set for a few days so maybe the pressure will drop off. I think it does anyway, but I'm not sure how much. Getting a face full of 60 psi gasoline doesn't sound like my idea of a fun time.

Worse comes to worse I can just have it towed up there I guess. I've got AAA so it wouldn't cost me anything. Luckily I've got the plan that allows for up to 100 miles or so on a tow.
 
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