Dyno video from Shootout

David Neibert

SCCoA Admin
My 91 SC pulled 490 rwhp & 451 rwtq in the Shootout dyno competition, which was enough to win my class. Big thanks to Jacob Royer for his old plug wires.


[youtube]nGosqLIma8Q[/youtube]


David
 
What has been your highest on this Dyno? Was this pull with mechanical issues? Breaking up etc?

Ricardo,

Highest I've pulled on that dyno was 498 several years ago (on race tune with meth injection), when we were at hotel in Winchester, KY. Yes this pull was made on my street tune with methanol injection turned off because I couldn't get it to rev cleanly with methanol turned on. It was actually breaking up slightly on this pull, and got progressively worse (see attached dyno sheet). I have a new Motorcraft coil pack, LiveWire plug wires and a set of NGK 7317 plugs all waiting to be installed this weekend.

David
 

Attachments

  • Neibert Dyno 490 rwhp 2018 Shootout.pdf
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Interesting how you were able to duplicate the results with less timing and no methanol.

What do you think can account for similar results on two completely different settings.

Any other hardware changes?

On a side note so was the methanol acting up or it’s ignition related or both?
 
Interesting how you were able to duplicate the results with less timing and no methanol.

What do you think can account for similar results on two completely different settings.

Any other hardware changes?

On a side note so was the methanol acting up or it’s ignition related or both?


Maybe it was a little leaner without methanol, but I imagine biggest difference was new Precision converter with 3000 stall vs the Dirtydog 3500 I had. Pretty sure methanol system is okay and real problem is ignition that is made worse when methanol is used. I already installed the plugs, wires and coil pack mentioned above, but decided to also add a new DIS module before starting it. If all goes to plan it will be running tonight. Her are a few pictures I took Sunday.

IMG_2523 small.jpgIMG_2525 small.jpgIMG_2526 small.jpgIMG_2527 small.jpgIMG_2537 small.jpg

Thanks, David

PS: Ricardo, Once I'm sure the methanol injection is working correctly I'll ship your controller back.
 
Installed the new aftermarket DIS module before starting and it was not running well when started. Tach needle was all over the place, running rough, then a CEL came on and it stalled. Took it back to O'Reillys and got another one I'll try tonight. Oh yeah it started and ran fine with my old DIS module. I just wanted all new ignition parts to get rid of misfiring under load at high rpm.


IMG_2543 small.jpg

David
 
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Dave I kept having that probblem years ago around 5,500 rpm. First thing took out the screaming demon coil pack put the factory one with probably 170k on it that helped I think I could get up to 6k rpm before it started misfire. Tried every spark plug you can think of the iridium made it way worse. Ended up with cheap Autolite copper core 103's I think gapped around 19-22 got the rpms up to 6,750ish.
But I allways have a voltage drop in the higher rpms I have 14+ volts at idle and up to around 5k rpms then the voltage starts to drop rapidly down around 11.2 volts at around 6,700 rpm. This in my theory is why the factory coil pack and copper plugs work better in my setup, I'm sure the aftermarket things would excel if I had the voltage to support them, but that's a problem I'm still working on.
 
Look at a billet alternator from mechman, I just installed mine last weekend and I'm over 14v all the way thru 6200 rpms.
 
I'm also in process of getting an aftermarket coil that is much better then the offerings out there like screamin demon, MSD, etc that was researched by a couple of the turbo guys here. It will require to change the harness plug and run HEI style distributor cap wire ends, which 3.8 NA wires or a custom set will be needed also.
 
I will look into that alternator, the SC project is on the sidelines for a bit me and the daughter have been working on restoring a truck for her the last year and a half. I do know at that time I was looking into a alt setup from a late model 5.0 Mustang you can rev them way high and don't seem to have any voltage problem
 
They are not cheap, but you will not find any modified stock style alternator that will come close to its specs. They are custom built and pullied according to your needs, and fully tested. Does require running extra 4ga. ground and positive wires.
 
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Mr Zimmer,

Please post up a tech thread and share the coil mod/system you r doing when you've got it all lined out. Sounds like a good one,

Thanks,

Adam
 
Ya I can. Its ~$100 plus a set of whatever wires you want. I can also make an adapter harness that will let you use a stock coil if ever needed.
 
Installed 2nd DIS module from O’Reillys and car wouldn’t even start. Installed my old Motorcraft module and it runs fine. Took it for a test drive and even with methanol turned up too high it didn’t miss a beat. So I’m calling it fixed. If I had to guess what fixed it, I think it was the new Motorcraft coil pack.

David
 
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Dave I kept having that problem years ago around 5,500 rpm. First thing took out the screaming demon coil pack put the factory one with probably 170k on it that helped I think I could get up to 6k rpm before it started misfire. Tried every spark plug you can think of the iridium made it way worse. Ended up with cheap Autolite copper core 103's I think gapped around 19-22 got the rpms up to 6,750ish.
But I always have a voltage drop in the higher rpms I have 14+ volts at idle and up to around 5k rpms then the voltage starts to drop rapidly down around 11.2 volts at around 6,700 rpm. This in my theory is why the factory coil pack and copper plugs work better in my setup, I'm sure the aftermarket things would excel if I had the voltage to support them, but that's a problem I'm still working on.

Good info thanks for sharing. I had XP103 iridium plugs gapped to about .030 (see picture), and now I'm using NGK 7317 that look like the copper Autolite 103 plug gapped to .030. I had very similar voltage issues in the past and tried a variety of alternators with varying success. Last year I went back to the stock SC alternator with a 3" under drive pulley and it is holding close to 13 volts at WOT. I'm also a big believer in the stock coil pack and plan to buy another new one for a backup.

IMG_2524 small.jpg

David
 
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Good info thanks for sharing. I had XP103 iridium plugs gapped to about .030 (see picture), and now I'm using NGK 7317 that look like the copper Autolite 103 plug gapped to .030. I had very similar voltage issues in the past and tried a variety of alternators with varying success. Last year I went back to the stock SC alternator with a 3" under drive pulley and it is holding close to 13 volts at WOT. I'm also a big believer in the stock coil pack and plan to buy another new one for a backup.

View attachment 69061

David
Glad to hear your pinning it down. I'm running close to 10:1 compression and 24ish # boost probably why the car seems to like the tighter gap on the plugs.
I have tried several alt myself and best so far is 6g but I keep ruining them, one on it now is brand new and I put a under drive pulley on it to slow it down in the higher rpms seemed to be working ok when I parked it but never got any track time with it.
 
Sounded pretty good on the dyno to me.

Hi Micah,

It was running pretty good on that first pull (swapped plug wires just before going on dyno) and it only stumbled a little at the hit and above 6300. The 2nd pull was a lot worse making 480 and it continued missing the next day on the track, really bad if I turned on the methanol. Runs great now, even with the methanol on. To reduce misfiring I was short shifting at around 5500 in 1st and 2nd, but as soon as I hit 3rd it was snap, crackle, popping.

David

PS: Missed you and Tonya at Rods & Hogs & Shootout.
 
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