Moment Of Inertia - Reduce MOI & Gain Horsepower

Originally Posted by tomtom72

Hey Craig, thanks for posting this info!

I like the one about the nylon bolts.....I'm gonna look into that as I'm going to swap my top end parts and I bought new OE coils to replace my Jegs coils.

Hey Tom,

Glad you could make use of the info. Did the Jegs coils give you issues?

[tomtom72]

Craig,

To be honest I'm not having an issue with the Jegs coils that I can put my finger on. It's just that the car don't seem as crisp on the gass and I have a slight shake....can't get the nickle to balance easily & consistantly....at idle.

The scan is clean. I got RC's & magnecore 10mm wires, new plugs, PCV's & the rubber, no under plenum vac leaks out of the 2* system anywhere. Pump runs for three seconds, maybe five on start up and then never comes back on, ever. Battery is up to it, and the alt is maybe a bit questionable..I have to do some more testing on my own. I got the OE/replacement coils so I figure to do them when I swap to my ported stuff. What the heck, they're right there...

Ya know when you think "Damn, it's just not sharp. Eh, what the heck is it?"

The only joker in the pack is the Jegs coils, and the somewhat questionable reputation of the aftermarket stuff vs the real OEM stuff for the LT5's application...you know we are the only motor to have coils living in hell!


Tom

Originally Posted by tomtom72

Craig,

To be honest I'm not having an issue with the Jegs coils that I can put my finger on. It's just that the car don't seem as crisp on the gass and I have a slight shake....can't get the nickle to balance easily & consistantly....at idle.

The scan is clean. I got RC's & magnecore 10mm wires, new plugs, PCV's & the rubber, no under plenum vac leaks out of the 2* system anywhere. Pump runs for three seconds, maybe five on start up and then never comes back on, ever. Battery is up to it, and the alt is maybe a bit questionable..I have to do some more testing on my own. I got the OE/replacement coils so I figure to do them when I swap to my ported stuff. What the heck, they're right there...

Ya know when you think "Damn, it's just not sharp. Eh, what the heck is it?"

The only joker in the pack is the Jegs coils, and the somewhat questionable reputation of the aftermarket stuff vs the real OEM stuff for the LT5's application...you know we are the only motor to have coils living in hell!


Tom

Tom,

I wish I could help but I'm just a novice. By the way, how do you like the Magnecor wires. I have the same in mine, brand new and I have been having static over the radio and even CD. Do you have issues like this with these wires?

I just want to get to the day when this Z will just have to put gas and drive. I don't want to mess with anything and just drive. If it keep pissing me off I'm going to part it out since it worth double and just walk in the dealership and get a C6. Gotta love these Zs!

[Pete]

Solution,always try to use OE parts.

I have AC Delco replacement wires for 4 years,AC Delco plugs and OE coils,65k miles car runs 128-129 MPH without missing a beat.

The rest are snake oils.

Just my thoughts,FWIW.

Pete

[tomtom72]

Craig, That's a bit strange about your set of magnecore wires. Mine don't do that. However, I looked under my rear 1/4 and I re did the antenna ground using GK's star washer + dielectric like he suggested for the SIR sensors. I figured it can't hurt anything. When I did the 1st plenum pull, I did the same to every ground wire I could locate also.

I agree with you Pete. Most times there is no substitute for the OE stuff's Q/Control. I bought those wires when I was collecting parts to do my first plenum pull....because my OE injectors went belly up because of the alcohol. I was soooooo nervous as a newbe that I swore that I was never gonna do this again.....

I laugh at myself now when I think about my mind set prior to my first plenum pull.


Tom

[XfireZ51]

Tom,

I'm using MSD coils and 8.5mm spiral wound wires. They work great in combo with NGK plugs. When you say that "the scan looks clean" what does that mean? No codes? Is the scan any different than prior to the changes?

[tomtom72]

Dom,

Let me establish my lack of sophistication as I'm still trying to get my mind around C.O. Probst's book on vette EEC.

I scan it with my MT2500 unit at idle in closed loop. I compare the displayed info to pg 6E- something that shows a data snap shot. No DTC's. I haven't reached the "data logging" point yet, but I did cop a laptop cheap. I figure when I feel I have learned & understood what is in Probst's book I'll go get a cable & software so I can actually see what my car is doing under different throttle & load situations. I'm a bit (sic) behind the learning curve on this stuff. I even thought of driving around with my scanner hooked up, but I felt that was a bit much...

I did the coil swap at the first pull so the only scan I had was a car with bad injectors. I did another scan after the injector r&r just to see if I was close to the book numbers. It was, and subsequent scans remain within the book numbers except for when I do find things like O2 sensors getting lazy. I do the r&r on the indicated parts and rescan to make sure I "got" the issue.

I think that it's a case of I'm getting used to a 375 hp car vs all the regular cars I drove for the 20 yrs between corvettes. Now I "think" I can actually feel the performance difference in my motor under "heat soak" vs "non heat soaked" conditions...... A butt dyno isn't that good!


Craig, I'm sorry for hi-jacking your thread.

Pete,

Thanks, good advice and I think I'll get some OEM wires (without LT5 on it).

Tom,

No problem, I'm just a sponge trying to learn every bit I can from everyone.

[RICKYRJ1]

Sorry Craig , don't mean to hi-jack your thread. Tom do you want the use of my garage for the work you plan on your car? You can leave it overnight if need be, I can drive you home or you can stay the night. Let me know, I owe you Big Time for that cab ride home from BG.

[tomtom72]

Thanks Craig, I'm right there along side taking notes myself.

Hey Rick.... you be the man, dude! Where's yours, still out at Marc's?

Thanks for the offer, the cab ride was my pleasure! I don't think I'm going anywhere to soon. It's been sittin for 4 weeks. I went to see if the battery would start it yesterday.......drum roll please....

Good news = battery is good & car started up fine, a little long on the cranking perhaps........makes me go hummmmm?

Bad news = clank, clank, clank goes the Fly wheel. I was late for a political union meeting so I eyed up the vacuum lines & yanked on the wires & sniffed the exhaust.......as it was still in the A.I.R. cycle. Ran fine when I put it away. Gonna bring some Techroline with me when I go back tonight. Good thing the weather forecast is good for al fresco auto diagnostics this weekend!

Ya know sometimes I miss those old cast iron sbc's, aluminium can be a right PIA sometimes....like when you have to move the car 5 miles just to do diagnostics! Just shoot me, please, now, uh why is it always august with my toy?

Later guys

Tom