fbody_brian

I have 3 different ICMs, it does it with all of them.

Yes, head gaskets have been changed. I believe they were the impala head gaskets. I will try a smaller gap and see if it helps.

I've checked all the primaries with an infrared thermometer and they are all pretty close, but that was at idle. I'd love to pick up a mph or two in the 1/4. I'd really like to see it above 110 and in the low 12s.
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Kevin97ss

Would you describe the sound as a clatter?

fbody_brian

the sound gets more "buzzy", don't know that I would call it clatter.
I am going to swap the opti and get new plug wires.
A spare optispark can't be a bad thing​​​​​​.

I won't really have time to mess with it much until after the holiday​​​​​​s.

Kevin97ss

I had a very similar thing going on years back with a set up like yours. It ran similar numbers too, but would just hit a wall @ ~6200. Blowing the tire off in first it would just hang @6200 and not hit the limiter. At the track, top of second and third just before the 6400 shift point it would let out a clatter noise and nose over.

It turned out that the lifters were bleeding down. They were early comp R's, supposed good ones, touted as "anti pump up". Well they did not pump up but they would bleed down and fully collapse.

I don't know if this is your issue but it does sound similar.

bufmatmuslepants

iTrader: (3)

This sounds like the opti to me. I agree with getting a ryobi cheapo temp gun and shooting the primaries and see if 1 is cold, that's how I found I had a wire arcing out to a motor mount. Taylor 8.2mm wires are good and cheap, but I wouldn't jump to that yet. First try some dielectric grease on the plugs and see if that helps and reposition all wires away from metal, even moving them 1" farther in can stop an old spark path. When a wire arcs through the wire it creates a little carbon trail making it easier to arc out that spot, so moving them 1" can move that path away. The next step would be a new opti with loctite on the screws.

If a cam peaks at 5700, you should shift at 6500. Short winded rule of thumb is split the shift drop over the peak, so with a shift rpm drop of 2000rpm, it's 1000rpm over and falls to 1000 rpm under. Really it's about the torque at each rpm * the gear ratio of the trans, making the torque being applied to the rear end be equal before and after the shift knowing the gear ratio multiplying the output of the engine is less at the next gear, but without a dyno of that cam its harder to calculate, but on my stock cam which peaks at 5200 I shift at 6300 for best times.

pantera_efi

iTrader: (1)

Hi Brian, thanks for your purchase.

I believe your Valve Float report is OK as you stated the 1.6 Rocker Arms made no change.
The Lifter "bleed" Tech could be possible with better knowledge gained when a specification of Spring Nose Pressure and Valve Weights are given ?

I would like you to measure your coil voltage at WOT 6K+ RPM with the New Opti ?

That report should be the same as your Battery Voltage.

Lance

ElkySS

iTrader: (6)

You ever figure this out? I'm missing 80 rwhp, hoping you might have the fix.

ElkySS

iTrader: (6)

Just thought you'd like to know, It seems I've fixed a very similar problem by replacing the coil. I thought I had an MSD coil but after I got it off, I noticed it was a Streetfire (still made by MSD but is there budget brand). I replaced it with an MSD and noticed smoother idling and more power up top. My car has been down 80rwhp and I think this fixed it, though I haven't had it on a dyno yet.

pantera_efi

iTrader: (1)

Hi All, I have both the OBD-1 AND OBD-II coil for distributed power ignition.
This is a higher than OEM output coil with faster charging good for increased RPM.
Primary = .28 Ohms
Secondary = 8.8K Ohms
Primary Inductance = 3.2mH
Turns Ratio = 134:1
Rated Voltage = 45KV +

Lance