Going back to the Dyno today! (UPDATE - NOT GOOD)

Thanks to the FM members (Mikes66, Motorhead, 1Bad88GT, etc.) that helped me with this thread:

http://www.fordmuscle.com/forums/all...ion_58968.html

I've made several changes, including:

Much bigger 14" x 3" offset air cleaner with a K&N filter (will definitely take care of any restriction if there was one). See new versus old HERE.
Secondary jets 8% leaner.
Accelerator pump adjusted to biggest shot.
Brand new MSD epoxy-filled coil (old one was leaking bad).
New Autolite Racing spark plugs gapped correctly.

Some of those things will help more than others, some possibly not at all, but all I'm hoping for is 331 BHP, which brings me to a question:

Figuring 18% drivetrain loss, is that 331÷1.18=281 RWHP? Or is it 331x.82=272 RWHP? I've heard it done both ways. But I think the second way makes more sense: 272 RWHP = 82% of the estimated flywheel HP.

Of course, I wouldn't mind over 300 at the rear wheels, but the 1 HP per 1 Cubic Inch will make me happy.

Anyway, I'll let ya'll know how it goes!

<font size=-1>[ This Message was edited by: 89Trooper on 5/6/07 5:33am ]</font>

Good luck! As far as the math goes, it really doesn't matter because you're not gonna be exactly 18% anyways... but if you want to be choosy, since it's an "18% loss", that would be 18% of the original value, or Loss = .18x331, and RWHP = 331-loss, which by replacement RWHP = 1x331 - .18x331, then factoring the 331 yeilds RWHP = 331x(1-.1[img]/forums/images/smiles/icon_cool.gif[/img], therefore RWHP = 331x.82, make sense? [img]/forums/images/smiles/icon_lol.gif[/img]
[addsig]

BTW, if you have room, and enough dyno time, once you get it all dialed in with the open element air cleaner, try your old air cleaner setup again, keeping in mind the old air cleaner will yeild a slight gain in hp durning normal driving conditions (vs at the dyno) from cooler air.
[addsig]

Thanks! I'll need all the luck I can get!

Makes perfect sense - and that's the way I thought was more accurate.

I may not have time for the old air cleaner, but if I'll take it along just in case.

No amount of luck could help me.

The clutch slipped both times. Until he had to back off the gas, the A/F ratio was much better leveling off at 13:1, so I know the power would have been there. It still got about 265 BHP with the clutch slipping practically the entire time.

Here is the chart:

http://i47.photobucket.com/albums/f1...gine/dyno2.jpg

He also printed the RPM-to-MPH chart. The green line shows approximately how fast the tires SHOULD have been spinning compared to the red and blue lines which show how bad the clutch was slipping.

Time for a new clutch... one that can handle some HP.



<font size=-1>[ This Message was edited by: 89Trooper on 5/6/07 8:50am ]</font>

What kind of clutch are you running now? I run a McLeod dual friction (single disk not the dual disk) and I love it, price isnt bad, pedal pressure is good and it holds the 489 like nobodies business
[addsig]

It's a ZOOM clutch. I forget the part number, though. I do remember worrying more about pedal feel and less about holding power because I didn't think my HP would ever get this high, so I'm pretty sure it doesn't have KEVLAR.

I still think it should hold it, but apparently it doesn't. And, I know the cable is adjusted properly.

So I will be doing some research on a new clutch kit.

Tom, sorry to hear, but at least this proves something, that the tuning we did to your carb, really found that lost power of yours. If I remember, you did not have any slippage before we tuned your car, and a clutch does not go bad in just a few days.

So, we found your power for you. Now you need to get it to the floor. Or we can de-tune your again....(lol)

Mike - no slippage at all before. And no slippage at all on the way home (no matter how hard I tried to make it slip). As we started tuning it and finding some more power, it would slip in 5th occasionally.

Is it that much harder to turn the barrel than it is to move 3000 lbs across the ground? Because, it was REALLY slipping on the dyno. The exact words of the guy when he got out of the car the first time... "The clutch is slipping like a bitch".

So we don't need to de-tune it. LOL. It's still good on the street. It did slip that one time before the dyno run that I told you about at 100 MPH.... but I don't do that too often.


<font size=-1>[ This Message was edited by: 89Trooper on 5/6/07 9:46pm ]</font>

You don't want it to slip and then you over rev the engine.....