I just got my digital6 ignition in the car and they recomend 50-60 gap for a car under 10:1 compresion. I run ngkfr5 plugs and think maybe i should pull them and gap them about 50 or so? I just want a few more horsepower. do you think i will gain anything? I have run 12.7@111mph trick flow wedge heads, super ram etc. Thanks

 

Super,
that's not a lot of info about your car, but anyway. That's cool you got the digital box. I'm not really familiar with the digital-6, though I know all about the digital-7 as the MSD engineers stole three of the feature designs directly from me back in 1995. Yes some hard feelings on that one.
Anyway I have never measured a power gain from simply widening plug gaps no matter what the combination, ignition, or sparkplug. There are a few tricks to sparkplugs that do work however.
My biggest power gain from a plug came from running an extremely cold Autolite#51 plug.
I have measured gains by simply clipping the ground straps back half-way to expose the tip & spark.
I have measured small gains by indexing the plugs so that the ground strap faces towards the intake valve.
I have measured gains by tuning (adjusting my A/F ratio & spark advance) while running wide gaps of .045 - .055 and after reaching max power closing the gaps down to .033
It is much easier for me to powertune with wide gaps until I reach the lean-limit or lean-misfire, then at that point I gap them tight and the misfires go away and power level goes up even more.
It is harder for me to find the lean-limit without overshooting the mark if the plugs are tight... especially with an MSD.

Good luck,
ODB



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*I do custom performance mods on Edlebrock Performer carburetors (dualplane intake mods in the works),
White 1986 Irocz, 305 with iron #416 heads,
383 with aluminum TFS heads,
Edlebrock Performer-RPM intake and Performer #1407 carburetor, +110hp shot of crack, 700R-4 tranny, Vigilante 2400 lockup converter, 3.25:1 Ford 9" rear, Mcreary Road-Stars, SLP-stainless 1.75" shortie headers & Y-pipe, single 3" Borla exhaust, Linginfelter-TPI camshaft part number 74216 pulls 17" vacuum solid. Cam specs 213/219 @.050 114-LSA, sometimes advertised at 216/219 @.050 112-LSA .462/.470 lift @1.5:1 ratio. Using Harland Sharp 1.65:1 roller rockers. MSD-6AL, billet distributor, multi-retard, blaster-3 coil, and RPM switch. SouthSide machine subframe connectors, SSM lift-bars, Moroso 4" underdrive crank pulley.

N/A runs 10.9 @124,
Crack-runs 10.3 @135
haven't run at track since Oct-99

 

Wow that car of yours realy screams! Do you think my car could run those numbers with a 383 and that cam with my super ram. I already have TFW heads and love them. I have a super ram,52tb,24#svo,3:73,5-speed,Hedman LT headers and 3.5 mufflex exhaust. Solid roller cams realy seem to help and if you only put 10k on your car a year you only need to adjust them twice a year.So i should try a cooler plug, cut the tip back a little and point them toward the intake valve. i have heard of people cutting the strip back to better expose the tip, thanks for the help

 

I think it would run great with those heads and cam. I chose to go carbureted partly for more power which I got. I would also guess the dualplane carb intake to be worth more torque at the shift-recover RPM than you would see with a mini-ram. Not sure about the super-ram, but if you mean the box intake from LPE/Acell then it's very likely to make even more torque. The only issue I have with that combo would be getting it tuned. If you do what it takes to tune it right, or have it done right, then it would be super.
I don't feel that 3.73 rear and 5-speed are the best match for a 383, but would be fun as long as it held together.
I can't personally recommend a solid cam from my experience. I don't know anyone who adjusts only twice a year... more like twice per night of hard running. They seem to be a huge huge pain. I've heard people say they are worth big power on a high RPM high horsepower engine, but I've not heard good reviews on a street engine with solids.
I think the 3.5" exhaust will be just right for a 383 as I plan to try that myself.
good luck
ODB


[This message has been edited by The ODB (edited February 08, 2001).]

 

You know ODB, you're growing on me more everyday. Hell, when you first said the MSD engineers stole your ideas, i started thinking, damnit, he's being a troll again. But then you explain your power tuning method and the brightest lightbulb i have seen in a while went off over my head. That is THE coolest idea i have every heard for tuning. I hope you don't mind if i borrow it, lol.
...ed

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Ed Maher - Moderator @ The Carb Board
92 Z28 Convertible - Quasar blue / Tan top
LB9 4L60 GU2 G80 - stock, soon to be sleeper

- Definitely prototypes, high powered mutants of some kind. Too weird to live, too cool to die

 

OBD, what idea is it that MSD stole from you?
You wanna share or do I have to give you a shot-o-crack?

 

Back off motherfu-ck-er....I'LL KILL YA!!

PS: Viva Las Vegas!

 

Thank you very much Ed. Borrow any ideas you like.
I encourage anyone to do their own tests to see what their engine likes best. If my hints or advice saves them some $, time, or trouble then that's great.
I have a couple other sparkplug mods in the works, but keeping the ideas under wraps for certain reasons right now. When they are fully tested and I have a patent they will come out.
thanks again.
ODB