It's energy suspension if I remember right. Don't hold me to it but I'm sure it's somewhere else in the thread. Probably Poly
Black Jack: Quarter mile Test n Tune Sunday!
- Thread starter FastDriver
- Start date
I wonder if some kind of vibration damper mounted to the loop could have kept it calm. You know those circular bushing like things you sometimes see bolted to the frames in engine compartments.
Talked to the guy who welded in my tq boxes. He said connecting it to the trans tunnel may kill the resonance. I'm not interested. I never had a problem with old loops. I just thought I was getting away with an easy install.
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With the vibration finally resolved and Black Jack back together and driving great, I'm heading to Rockingham on Sunday to make some quarter-mile passes.
I've got several things I want to work on:
- NA timing: Dial in WOT timing on 93 octane, using trap speeds to evaluate changes.
- Nitrous timing: Once the NA tune is sorted, experiment with timing retard on the 150-shot.
- Launching: Find a two-step RPM and clutch-slip technique that lets me launch on nitrous without bogging or blowing the tires off.
- Front Konis: Change rebound from 1 turn off full loose to full loose, and compression from 2 to 5 clicks from soft, hoping to improve front-end rise and weight transfer.
- Rear Konis: Start with my street/autocross settings of 0.75 turn rebound and 2 clicks compression. Depending on how the Nittos respond to harder launches, I may experiment with rear damping.
The whoopings Larry's GTO handed Black Jack at Foxtoberfest made it pretty clear that my street/autocross suspension setup and Nitto drag radials aren't getting it done as is off the line at the strip. I never saw better than a 2.0 60'. But I think there's plenty of room for improvement, even before switching to slicks (I'm really starting to champ at the bit... Can't find em on FB marketplace nearby in the right size... Starting to feel the urge to pay retail).
I've also got a few things on the to-do list, some of which I might tackle Saturday:
- Driveshaft safety loop: Install a conventional loop ASAP, especially since I'm actively hunting for the right wheels to run slicks.
- Zeitronix gauge: Install my dual WBO2 gauge.
- Instrument cluster: Address the airbag light and replace the bulb behind the lower-left temperature gauge that went out this week.
- Radiator: Replace my slightly leaking Ron Davis with an SVE radiator I picked up for $100. Probably won't get to this before Sunday.
Looking forward to seeing how much I can improve the launch and 60-foot without giving up the street and autocross setup I like so much.
I've got several things I want to work on:
- NA timing: Dial in WOT timing on 93 octane, using trap speeds to evaluate changes.
- Nitrous timing: Once the NA tune is sorted, experiment with timing retard on the 150-shot.
- Launching: Find a two-step RPM and clutch-slip technique that lets me launch on nitrous without bogging or blowing the tires off.
- Front Konis: Change rebound from 1 turn off full loose to full loose, and compression from 2 to 5 clicks from soft, hoping to improve front-end rise and weight transfer.
- Rear Konis: Start with my street/autocross settings of 0.75 turn rebound and 2 clicks compression. Depending on how the Nittos respond to harder launches, I may experiment with rear damping.
The whoopings Larry's GTO handed Black Jack at Foxtoberfest made it pretty clear that my street/autocross suspension setup and Nitto drag radials aren't getting it done as is off the line at the strip. I never saw better than a 2.0 60'. But I think there's plenty of room for improvement, even before switching to slicks (I'm really starting to champ at the bit... Can't find em on FB marketplace nearby in the right size... Starting to feel the urge to pay retail).
I've also got a few things on the to-do list, some of which I might tackle Saturday:
- Driveshaft safety loop: Install a conventional loop ASAP, especially since I'm actively hunting for the right wheels to run slicks.
- Zeitronix gauge: Install my dual WBO2 gauge.
- Instrument cluster: Address the airbag light and replace the bulb behind the lower-left temperature gauge that went out this week.
- Radiator: Replace my slightly leaking Ron Davis with an SVE radiator I picked up for $100. Probably won't get to this before Sunday.
Looking forward to seeing how much I can improve the launch and 60-foot without giving up the street and autocross setup I like so much.
What's the current jetting and what's it call for on the 150, most kits are way to fat in my experience.
I'm usually better at keeping notes. Looks like 67 & 32. Keep in mind that Black Jack is already running in the 12.7 - 12.8 territory at WOT NA. It's deep in the 11s on nitrous. I was aiming for 11.5, but it may be slightly fatter or leaner throughout the rpm band and if bottle pressure changes.
Is that what's in it now or what you plan for the 150shot , 67 is usually good for around 165 170hp for most single jet kits, fuel jet looks small for the rating. most kits want at least 38 for flowing fuel pressure at 35-40psi, with a 62- 67 on the nitrous side as a starting point depending on the kit. unless someone all ready did a tune up for the kit might want to double check. I think the basic zex box only had a small .075 selonid and with how there designed and the fail safes, I was never a fan of them. I have seen people chase there tails from the failsafes pulsing one noid. There's a few video on YouTube showing a box torn down, the noids are tiny, smaller than ones I use for a purge.
With a wet nozzle and baseline for 100 shot I always used .052/.031 and lowered the fuel jet from there, and .062 / .038 for 150, usually .004 is about the max you want to drop a fuel jet size on most combos, all most all mine where just pieced togther with older Hurst style .125 noids and a wet nozzle. had them on pretty much every mustang I owned. Any thing over a .80 jet with an efi single nozzles on the normal fox body style intake is just pushing the risk of a backfire too much in my experience even with the big single sho shark nozzle and 4an feed lines. I had pretty much the same combo blackjack but on the stock a9l with a t5 and 3.73's, it was just a frpp ford gt40x headed crate 302 that was in my old reef blue 93 gt with a cobra intake when I bought it, ran 11.20's on the bottle with a leaned out .052 100 jetting. Car was full weight 93gt sunroof car, still had the ac, ps and stock clutch fan but it was on 26" bias et streets so was mostly getting 1.5-1.6 60fts, trap speeds where a little higher then yours though.
With a wet nozzle and baseline for 100 shot I always used .052/.031 and lowered the fuel jet from there, and .062 / .038 for 150, usually .004 is about the max you want to drop a fuel jet size on most combos, all most all mine where just pieced togther with older Hurst style .125 noids and a wet nozzle. had them on pretty much every mustang I owned. Any thing over a .80 jet with an efi single nozzles on the normal fox body style intake is just pushing the risk of a backfire too much in my experience even with the big single sho shark nozzle and 4an feed lines. I had pretty much the same combo blackjack but on the stock a9l with a t5 and 3.73's, it was just a frpp ford gt40x headed crate 302 that was in my old reef blue 93 gt with a cobra intake when I bought it, ran 11.20's on the bottle with a leaned out .052 100 jetting. Car was full weight 93gt sunroof car, still had the ac, ps and stock clutch fan but it was on 26" bias et streets so was mostly getting 1.5-1.6 60fts, trap speeds where a little higher then yours though.
That's a lot of good nitrous experience and information I didn't know, so I appreciate the feedback. Your old GT sounds remarkably close to Black Jack! GT40X heads check, A9L check, 3.73s check, Cobra/GT40 intake check. AC, PS, sunroof, and full weight check. You didn't mention cam. Mine has an E303 and a T56 instead of the T5. I trust the T56 more, but its 2.66 first gear versus the T5's 3.35 has really hurt my 60-foot times. I actually launched better with the T5 on stock-size all-season radials than I do now on larger drag radials. I'm hoping a more aggressive two-step launch on slicks after dialing in the struts and shocks will knock a few tenths off. I'll be very happy with 1.6s, as this is going to stay a daily/autoX/weekend drag TnT car, not a balls out straight line car.
This is my first nitrous kit. I specifically asked the shop for a 150-shot, and they sold me the ZEX 82023. When I discovered it was only rated to 125, I questioned them, but they said they'd dynoed one to around 175 hp.
I just confirmed the fuel jet is .032. I started richer, was seeing AFRs in the 10s, and gradually leaned it out while watching the wideband and datalogging. I've been targeting 11.5, and it's generally staying in the 11s. But your point about the small ZEX solenoids makes sense. Maybe I'm simply not flowing as much nitrous as I think.
That would fit some of my results. On the original 100-shot, the car went from 274.57 to 339.78 rwhp, a gain of only 65.21. More recently, my eighth-mile trap converted to roughly 117 mph in the quarter, versus 114.45 on the 100-shot. Not much improvement for supposedly adding 50 hp. So, I'm getting 90-100 rwhp out of it as it sits. Maybe timing will wake it up.
I'm currently pulling 6° of timing and plan to experiment at the track tomorrow, comparing trap speeds, logs, and plugs. I'm not interested in going any bigger with the shot. Just want to get the most out of what I have without sacrificing reliability. I'll report back with what I find!
Cam should have been a E303 but never verified it, was the ford crate engine in it when I bought the car, had crane rockers and the basic bolt on stuff for T-body and exhaust, Car was from NY with rusty rear quarter on the passenger side, hammered paint and had the typical it breaks up a 3k efi problem so many gave up on back then, mostly from beat up wiring, not a failing ecu on that one. I picked it up cheap, fixed the efi issue, but never did the body work. I really have a hatred of owning none solid roof cars and I think the sunroof was siliconed shut when I bought it, never opened it once. I just kept it as a cheap beater until I sold it cheap for a different notch, no crazy suspension just none adjustable arms on it when I bought, had Gabriel shocks. Still put the welds and nitrous on it when I took it to atco. 117 is good enough for mid 11's with a better 60ft in 1.5-1.6 which is doable on your type of suspension on better tires. 1.3- low 1.40 is where more track oriented cars typically land on combo like that with slicks. I've had too many similar combo cars over the years but the reef 93 was pretty damn identical.
Here's a video of inside one of the zex boxes not mine but gives you an idea, you might be better off picking up some better selonids down the line or borrowing some to test and just wiring in a Basic Hobbs switch for a fuel cut off. That's pretty much how I did all mine, honestly ran locked timing and rarely pulled any on a 100shot, 150 some cars it needed a degree or 2 vs na two but the plugs will tell you. the 2 per 50 and factory jetting on most kit is the we share no liability here is an as safe as we can give you generic tune up. But the 67-32 spread is surprising to me for a rated 150, if kits only rated at 125 was that just from testing the jetting previously or did someone send you a jet chart for a different kit? The video you posted of the previous run cars not even chooching any at launch or between shift so suprised at a 11.5 afr range on the bottle.
View: https://www.youtube.com/watch?v=_6DFZfNfwxc
Here's a video of inside one of the zex boxes not mine but gives you an idea, you might be better off picking up some better selonids down the line or borrowing some to test and just wiring in a Basic Hobbs switch for a fuel cut off. That's pretty much how I did all mine, honestly ran locked timing and rarely pulled any on a 100shot, 150 some cars it needed a degree or 2 vs na two but the plugs will tell you. the 2 per 50 and factory jetting on most kit is the we share no liability here is an as safe as we can give you generic tune up. But the 67-32 spread is surprising to me for a rated 150, if kits only rated at 125 was that just from testing the jetting previously or did someone send you a jet chart for a different kit? The video you posted of the previous run cars not even chooching any at launch or between shift so suprised at a 11.5 afr range on the bottle.
View: https://www.youtube.com/watch?v=_6DFZfNfwxc
Reef Blue is absolutely my favorite Fox-body color, and despite what you said about the paint, I think your old GT looked great!
Black Jack's paint isn't great either, and I've never bothered much with the bodywork. A truck hit it and I replaced the hatch and taillight, then a deer took out the left headlight. I cleaned off some rust and spray painted down in the cowl. Cleaned up a quarter sized hole in the right rear lower splash panel behind the rear tire. That's about the extent of my bodywork. One day I might paint it, but I'm honestly not looking forward to caring about what happens in a grocery store parking lot. It's a great daily driver partly because I don't have to care!
I'm impressed you were getting those 60-foot times with nonadjustable arms and Gabriel shocks. Were you still running stock springs? It looks fairly close to stock ride height.
You've definitely got me thinking about that fuel jet. I'll be datalogging at the track tomorrow and paying close attention. I don't mind running richer than optimal, especially with the possibility of uneven cylinder distribution. I'd rather leave myself some margin than chase every last horsepower. I'll bring my jets and may go back up to a .034 or larger fuel jet depending on what I see. I hear you about the lack of "chooching," but would you really expect visible smoke at 11.5:1? I've made probably 5–10 pulls on the current combination without any apparent issues, but that doesn't mean I can't improve it.
I've actually got another engine at the machine shop, so hopefully this one survives until the new combination is ready. But that's part of what I love about these cars. You can push them, work on them yourself, and if something breaks, it's not the end of the world.
The day before Foxtoberfest I had the entire driveline out of Black Jack. I've had it out a couple of times this year, along with welding the axle tubes and reinforcing the torque boxes with Wild Rides Battle Boxes. I love that I can tear this car apart, put it back together, drive it every day, autocross it, and take it to the dragstrip.
It's a much better car than when I bought it, and I still don't think you can buy anything new worth driving for what I've got invested in the whole thing. That's what makes these Foxes so much fun.
Black Jack's paint isn't great either, and I've never bothered much with the bodywork. A truck hit it and I replaced the hatch and taillight, then a deer took out the left headlight. I cleaned off some rust and spray painted down in the cowl. Cleaned up a quarter sized hole in the right rear lower splash panel behind the rear tire. That's about the extent of my bodywork. One day I might paint it, but I'm honestly not looking forward to caring about what happens in a grocery store parking lot. It's a great daily driver partly because I don't have to care!
I'm impressed you were getting those 60-foot times with nonadjustable arms and Gabriel shocks. Were you still running stock springs? It looks fairly close to stock ride height.
You've definitely got me thinking about that fuel jet. I'll be datalogging at the track tomorrow and paying close attention. I don't mind running richer than optimal, especially with the possibility of uneven cylinder distribution. I'd rather leave myself some margin than chase every last horsepower. I'll bring my jets and may go back up to a .034 or larger fuel jet depending on what I see. I hear you about the lack of "chooching," but would you really expect visible smoke at 11.5:1? I've made probably 5–10 pulls on the current combination without any apparent issues, but that doesn't mean I can't improve it.
I've actually got another engine at the machine shop, so hopefully this one survives until the new combination is ready. But that's part of what I love about these cars. You can push them, work on them yourself, and if something breaks, it's not the end of the world.
The day before Foxtoberfest I had the entire driveline out of Black Jack. I've had it out a couple of times this year, along with welding the axle tubes and reinforcing the torque boxes with Wild Rides Battle Boxes. I love that I can tear this car apart, put it back together, drive it every day, autocross it, and take it to the dragstrip.
It's a much better car than when I bought it, and I still don't think you can buy anything new worth driving for what I've got invested in the whole thing. That's what makes these Foxes so much fun.
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85GTStangGuy
5 Year Member
