Dyno Results are in, Pics - Holley Systemax Kit :sad:

Thanks for the advice ppl.
I'll post the graph w/ A/F up when I get home later.

The A/F stays good after the sound changes and the power drops. It's a smooth drop, not choppy.
The sound is like a vibration, or turbulence of air being resisted.

This was on a Mustang Dyno that a Single turbo 5L coupe just layed 450whp down on as I arrived.

The RPM on the dyno chart was from the computer, not either of the tachs.

Driveability is great, I rev it to 5200 and it feels ok.
Like I said, yesterday I raced my old Mustang (335whp on a dynojet, 102mph trap). It begain to pull on me a little at about 65mph, but we were even untill then.

I'm going to:
1. Get normal copper plugs.
2. Borrow a 24lb Pro-M MAF if I can find one and try it out.

Alright, here's the graph. The shape is not much like that on the Holley site.

Would iridiums really hurt HP/TQ ?

The power does seem low but on a Mustang dyno it isnt as low as you think. I would say on a dynojet your over 260 rwhp, which isnt bad, but definately wants more RPM...

Also your other car made 335 rwhp and only traps 102??? There is something wrong there also, should be well over 110 traps!

5L's here w/ similar combos but using TF TW heads usually make ~280hp on a MD.

That 335whp (and 358tq) was on a dynojet w/ my full weight 93 hatch LX.
Stock intake/heads/cam at 6.5psi of boost. The 1/4mi was run at 3500' elevation.

Some cars are fine with Iridiums. When I worked at the shop, we had cars come in all the time that wouldn't even run on them, usually GM's. Lots of drivability issues in Fords we fixed just by swapping out the plugs for OEM's. Platinums, Splitfires, Iridiums, all gimmics. They shouldn't even be allowed to sell them for most applications, they can really mess things up. Pay way more money to basically hijack your own car?

You a/f ratio is all over the place, it should be a nice soild smooth line, not like a set of rolling hills...I think you have problems elsewhere, the MAF would be the first thing I'd check to.

I made 330-340RWHP with the Holley kit, (cleaned up the intake and exhaust ports), 8.8:1 comp, AFM cam, 75mm TB, 30# inj 43psi of FP vac off, 80mm Pro-M and I also use a 76mm C&L with no issues. Car trapped 114-116mph, 1.7 60ft's. What heads do you have? The 2.02 valve or the 1.94? The newer heads from what I was told (these are what I ran) are PT#300-575 2.02 x 1.60 valve and are much better then the older style heads....they flow decent and make good power, they respond very good to a basic clean up.

I ran Autolite 65's gapped at .040 per Holleys reccomendation...