Black Jack: Mark VIII fan is installed
- Thread starter FastDriver
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The reason I axed was that you said you went from a 5 speed to a 6 speed and lost some HP. I know some of the 6 speeds have some pretty high OD gears ,
Gotcha. Yeah, I still dyno'd in 4th. The minor power drop could be the dyno, the day, the T56, the pullies... anything really. I am a little befuddled by losing 30 ft-lbs of tq, though.
Humidity can effect the numbers too.
I look at a dyno as a tuning tool.
The 'butt dyno' is far more accurate, only two readings, fast or slow.
I look at a dyno as a tuning tool.
The 'butt dyno' is far more accurate, only two readings, fast or slow.
85GTStangGuy
Advanced Member
True. But humidity, as well as temperature and barometric pressure, should automatically be compensated for in the correction done to get the test results to conform to SAE J1349, which is the standard for engine dyno testing.
The problem is that there's no real standard used to calibrate each machine prior to a run. Every dyno setup is an approximation.
There's no [calibration test weight]. Not to mention shops that like to give their numbers a little [bump]. It helps to sell dyno sessions.
Best dyno is the drag strip. Those numbers do not lie.
Don't pay any attention to the ET, look at the MPH. That is the true indicator on HP.
Don't pay any attention to the ET, look at the MPH. That is the true indicator on HP.
eh... it's the best, I agree... but... one is still not comparable to another. There's still no way around the conditions at the track or the calibrations of the dyno.
There are corrections for track altitude/temp ect.
I agree a bad track can hinder mph numbers.
Most tracks try to make the surface compatible for race cars. It they don't, there is usually a track that does.
I have raced other cars that are quicker (ET) but the mph was less (by as much as 7 mph) All that proved is that their 60' was a lot better, but they lacked the power to mph out the back end.
Here is a good source of information concerning how your car works.
Wallace Racing - Automotive Calculators
www.wallaceracing.com
I've seen 'em, man. I've built models around them and applied them through coded algorithms Ive written to datalogs. It's still just kinda 'best we can do' correction.
85GTStangGuy
Advanced Member
Yes, it is. I stand corrected. me->
<-youI see that on your dynos now.... didn't pay notice to it before. They were corrected to STD (which is SAE J607).
New Gauges:
Tonight I installed the new gauges. I borrowed my old gauge pod from Father Time/Snake Pit & installed the Innovate Wideband (MTX-L I think) & Autometer Fuel Pressure gauge. I still need to connect the white wire for the back-light & yellow to the EGR pin on the A9L for datalogging. I'm looking forward to being able to tune on AFR once I install the Moates Quarterhorse.
Headed to the shop for gears, an Eaton Detroit Truetrac & a new clutch:
Differential: Tomorrow I have an appointment to drop it off with Performance Auto & Chassis in Cary, NC. I like Mark & Mike, there. I'm having them install 3.73s & set up the new Diff. The limited slip in it was definitely some kind of upgrade from stock, given that it's running 31 spline axles, but it does struggle to get traction from the inside wheel when cornering under load, and the Truetrac should make a nice improvement. The Truetrac is the same diff as in Grover & it's always been great.
Gears: I believe the 3.73s will hurt me at the drag strip, because of the T56's 2.66 1st gear. I'm already launching from the limiter and can't cut 60' times like I could with the T5 + 4.10s. However, these will make for a better highway cruiser & daily driver, and it should give me a 5-6 more mph in 2nd, which will be very helpful at the Auto-X, this year. Also, on the spray, I expect to trap into the 120s at the dragstrip, and the 3.73s should get me in the 120-122 ballpark. And, who knows... Maybe I'll figure out how to launch with nitrous and get the 60' times back down to something reasonable. One nice thing is that I should just be able to use the Dakota app to correct the speedometer, now that it's tied to the signal converter.
Clutch: I ordered a Ram Powergrip clutch (p/n 98794T) and got it in, last weekend. It's supposed to be good for 550 hp. That should be good for more than I intend to throw at it. Plus, it's organic & so it should be smooth for street driving. I expect a heavier pedal, so I guess I'll just have to wear my big boy pants when I drive the car. I'm feeling a little guilty I didn't put it in myself, but to hell with it. I've got too much going on.
Edit: On 2nd thought, I'm not going to let the shop do the clutch. There's just too many little things around that T56 they can screw up that I am very particular about like the wiring in the trans/shifter area (Dakota digital converter which affects cruise control & speedo, reverse lockout, & line lock). I'm not really in a rush on the clutch anyways. The King Cobra's good for anything not involving nitrous. So, I can drive it through an Auto-x season if I want to.
Tonight I installed the new gauges. I borrowed my old gauge pod from Father Time/Snake Pit & installed the Innovate Wideband (MTX-L I think) & Autometer Fuel Pressure gauge. I still need to connect the white wire for the back-light & yellow to the EGR pin on the A9L for datalogging. I'm looking forward to being able to tune on AFR once I install the Moates Quarterhorse.
Headed to the shop for gears, an Eaton Detroit Truetrac & a new clutch:
Differential: Tomorrow I have an appointment to drop it off with Performance Auto & Chassis in Cary, NC. I like Mark & Mike, there. I'm having them install 3.73s & set up the new Diff. The limited slip in it was definitely some kind of upgrade from stock, given that it's running 31 spline axles, but it does struggle to get traction from the inside wheel when cornering under load, and the Truetrac should make a nice improvement. The Truetrac is the same diff as in Grover & it's always been great.
Gears: I believe the 3.73s will hurt me at the drag strip, because of the T56's 2.66 1st gear. I'm already launching from the limiter and can't cut 60' times like I could with the T5 + 4.10s. However, these will make for a better highway cruiser & daily driver, and it should give me a 5-6 more mph in 2nd, which will be very helpful at the Auto-X, this year. Also, on the spray, I expect to trap into the 120s at the dragstrip, and the 3.73s should get me in the 120-122 ballpark. And, who knows... Maybe I'll figure out how to launch with nitrous and get the 60' times back down to something reasonable. One nice thing is that I should just be able to use the Dakota app to correct the speedometer, now that it's tied to the signal converter.
Edit: On 2nd thought, I'm not going to let the shop do the clutch. There's just too many little things around that T56 they can screw up that I am very particular about like the wiring in the trans/shifter area (Dakota digital converter which affects cruise control & speedo, reverse lockout, & line lock). I'm not really in a rush on the clutch anyways. The King Cobra's good for anything not involving nitrous. So, I can drive it through an Auto-x season if I want to.
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Mindseye007
Active Member
what RPM did you launch at with those tires or did you feather the clutch? I love my 4.10's with my Z-Spec T5.I must say that the I am very pleasantly surprised! The 60' was as bad as I imagined it would be, but my ET was better! The car is definitely geared well for the trap speed and power band!
I am proud to present Black Jack's first timeslip, and its fastest ET to date! The last owner told me he ran a 13.5@103 best.
60': 2.24
1/8: [email protected]
1/4:[email protected]
I'm stoked that on its very first run it only ETed 0.06 seconds slower than the fastest ET I ever got out of my 1997 Corvette (bone stock) - a [email protected], despite 60'ing worse. The corvette used to run high 1.9s to 2.1s in the 60' with street radials.
I only got 2 runs in tonight, and on the second run, I treed much better with a .0547 reaction, and I really tried to slip the clutch, but these tires just weren't having it. It ran a
60': 2.31 60',
1/8: [email protected]
1/4: [email protected]
I also recently received the dyno files and will add them momentarily.
Chris
Mindseye007
Active Member
I really like the Centerforce Dual Friction ® Clutch that's what I am using, it grabs like $hit sticking to a blanket
Products - Clutch Kits - Full Clutch Kits - Dual Friction
var showFilters = ['Out of Package Weight LBS','Torque Capacity FT/LB','SFI 1.1 Approved','Ring Gear Tooth Count','Clutch Disc Diameter IN','Clutch Disc Diameter MM','Disc Type Sprung Solid','Disc Qua
www.centerforce.com
View: https://www.youtube.com/watch?v=ayLHjHM-A4U
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Mindseye007
Active Member
I Three have the Accufab 70mm installed for the last 7 years and no whistle sound.I too have an accufab 70mm.. It's in a box awaiting install in like 10 years.I hope it doesn't have the dreaded whistle that bbk/others have.
You'll have a little taller 1st than I did, but my best results on those old All-Seasons was launching slightly above idle, feathering the clutch briefly and then letting those short 4.10s & 3.35 1st gears (13.74 starting line ratio) do all the work. Now, my starting line ratio is ~28% taller and though I have the drivetrain to do it & stickier tires, I'm leaving from the limiter & still not achieving the same 60' I used to. Old best on 225/50/16 Goodyear all-seasons was 1.83. New best on 275/40/17 Nitto Drag Radials was 1.86. I'm guessing I'm going to need to get my nitrous set up to spray off of the line with a progressive before I get back to new bests.
I really like the Centerforce Dual Friction ® Clutch that's what I am using, it grabs like $hit sticking to a blanket
Products - Clutch Kits - Full Clutch Kits - Dual Friction
var showFilters = ['Out of Package Weight LBS','Torque Capacity FT/LB','SFI 1.1 Approved','Ring Gear Tooth Count','Clutch Disc Diameter IN','Clutch Disc Diameter MM','Disc Type Sprung Solid','Disc Quawww.centerforce.com
View: https://www.youtube.com/watch?v=ayLHjHM-A4U
I've used the Centerforce Dual Friction. No issues... chattered a little but not like my Specs.
I've always wanted to try a Ram Powergrip. So, I've got one on the garage floor, now. I'm not feeling particularly motivated to do it, yet. Need to get the quarterhorse in, get the twin disk in Grover, and do some other cosmetic things. Plus, my work life it hectic, but I imagine that I'll get back around to it later this year.
Well, lucky me. I was the fortunate one to get the Accufab 70 that whistles. Speaking of things to do, this is on the list. Wanna pull it off and round out the ridges around the IAC ports. I've been told that usually clears things up.
It's been almost 20 years now. I wonder if he ever installed it or if it's still sitting on the shelf.
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