COPO, Drag-Pak, CJ II, (FX) Secrets

Mark Yacavone · 01-27-2023, 09:31 PM

I happened to be at Speedworld for one of the first test sessions of the then new blown CJs. John Calvert, Gary Stinnett and a few others were there with the Brent Hajek cars.
The stick cars would just wring the tires off them and wouldn't lift the nose more than an inch. I remember thinking that these cars will be a bear to make consistent and competitive. I know it could be all about the clutch in the stick cars.
Fast forward to today... I see FX cars with big hp and torque numbers cutting great lights and wheelie-ing to lots of dead on runs, and winning eliminators, ..on 9 inch tires.
How is it being done? Timing? Starting out with minus numbers? Boost control? What else?
We hear that the COPOs don't use drive by wire. Do the others?

I'm thinking this thread might belong one floor down, if we get actual tech oriented answers.
Not sure we will. It might take membership in the Six Figures Club to find out ;-)

Billy Nees · 01-28-2023, 10:40 AM

Quote:

Originally Posted by Mark Yacavone

We hear that the COPOs don't use drive by wire. Do the others?

I'm pretty sure that the FFFords come as DBWs. I don't know about the DPs but I have heard a rumor that Larry Hill's DP uses a piece of string tied on the TB and looped around his big toe.

442OLDS · 01-28-2023, 10:59 AM

I don't know how much of a speed secret it would be,but it couldn't hurt.
The 9 inch tires that you are referring to are not really 9 inch tires.
Goodyear came out with a wider one in 2022,and Hoosier is making an even wider one in 2023.

Jack Matyas · 01-28-2023, 11:29 AM

Quote:

Originally Posted by Mark Yacavone

Fast forward to today... I see FX cars with big hp and torque numbers cutting great lights and wheelie-ing to lots of dead on runs, and winning eliminators, ..on 9 inch tires.
How is it being done? Timing? Starting out with minus numbers? Boost control? What else?
We hear that the COPOs don't use drive by wire. Do the others?

I'm thinking this thread might belong one floor down, if we get actual tech oriented answers.
Not sure we will. It might take membership in the Six Figures Club to find out ;-)

Markie - Did you really think any of us were going to just spit out our secrets??? I'm not so sure that even joining the Six Figure Club will help you .......But I will tell you I don't use DBW in my COPO's.

Mark Yacavone · 01-28-2023, 11:47 AM

Quote:

Originally Posted by Jack Matyas

Markie - Did you really think any of us were going to just spit out our secrets??? I'm not so sure that even joining the Six Figure Club will help you .......But I will tell you I don't use DBW in my COPO's.

Jacko, No. Actually I didn't...and so far we're still okay in this section. ;-)

Stan Weiss · 01-28-2023, 01:32 PM

I have seen data logs from a Ultra Street NOS car that is around the same weight, that was pulling over 2.2 G's on a 275 DR. If these new tires are lets say 255 I would think a min of 1.95 G's. So just a WAG for the 632.

60 Foot ET = 1.2241
330 Foot ET = 3.4843
1/8 Mile ET = 5.4284
1/8 Mile MPH = 126.1316
1000 Foot ET = 7.1115
1/4 Mile ET = 8.5372
1/4 Mile MPH = 158.1890

Stan

Doug Hoven · 01-28-2023, 02:52 PM

Quote:

Originally Posted by Billy Nees

I'm pretty sure that the FFFords come as DBWs. I don't know about the DPs but I have heard a rumor that Larry Hill's DP uses a piece of string tied on the TB and looped around his big toe.

I know the CJs we’re DBW from the factory, but I believe some have converted them to cable. The couple of factory showdown COPOs I have been around we’re all cable throttle. As far as getting down the track, mostly it’s in the tune. A lot of timing pulled on the launch. Not sure about boost control.

bigshow2966 · 01-28-2023, 03:52 PM

Geoff Turk is really covering the build of his BlackbirdX on Facebook. He hasn't put pedals in it yet, but has started the motor. I would guess his is DBW. They are on a 10.5 tire.

Keith 944 · 01-28-2023, 07:28 PM

i know jack has nothing to hide as i have seen him blow the tires off many times, however i have been watching a blue cobra jet that leaves like a four cyl. and come alive like a banshee going down track, so if its allowed, dbw, percentage is prob. whats happening, it seemed much more likely than just pulling timing, but is more than certain some form of traction control and from what i saw, it was deadly....

GUMP · 01-29-2023, 01:06 AM

It really doesn't make a lot of sense to take the throttle out. Modern ECU's have almost infinite control of timing. Shocks, tires, and gearing might want to be added into the equation when trying to figure out what makes the supercharged cars work so well?

I can tell you that every COPO that I have campaigned has run without limiting the throttle by anything other than the drivers foot.

01-27-2023, 09:31 PM	#1
Mark Yacavone Veteran Member Join Date: Mar 2002 Location: Miles From Nowhere Posts: 7,417 Likes: 2,582 Liked 4,453 Times in 1,694 Posts	COPO, Drag-Pak, CJ II, (FX) Secrets I happened to be at Speedworld for one of the first test sessions of the then new blown CJs. John Calvert, Gary Stinnett and a few others were there with the Brent Hajek cars. The stick cars would just wring the tires off them and wouldn't lift the nose more than an inch. I remember thinking that these cars will be a bear to make consistent and competitive. I know it could be all about the clutch in the stick cars. Fast forward to today... I see FX cars with big hp and torque numbers cutting great lights and wheelie-ing to lots of dead on runs, and winning eliminators, ..on 9 inch tires. How is it being done? Timing? Starting out with minus numbers? Boost control? What else? We hear that the COPOs don't use drive by wire. Do the others? I'm thinking this thread might belong one floor down, if we get actual tech oriented answers. Not sure we will. It might take membership in the Six Figures Club to find out ;-) __________________ We are lucky we don't get as much Government as we pay for..... Will Rogers Last edited by Mark Yacavone; 01-27-2023 at 09:36 PM.

01-28-2023, 10:59 AM	#3
442OLDS VIP Member Join Date: Sep 2004 Location: Elgin,IL Posts: 1,333 Likes: 5 Liked 262 Times in 100 Posts	Re: COPO, Drag-Pak, CJ II, (FX) Secrets I don't know how much of a speed secret it would be,but it couldn't hurt. The 9 inch tires that you are referring to are not really 9 inch tires. Goodyear came out with a wider one in 2022,and Hoosier is making an even wider one in 2023.

01-28-2023, 01:32 PM	#6
Stan Weiss Senior Member Join Date: Apr 2020 Location: Phila, PA Posts: 607 Likes: 0 Liked 545 Times in 291 Posts	Re: COPO, Drag-Pak, CJ II, (FX) Secrets I have seen data logs from a Ultra Street NOS car that is around the same weight, that was pulling over 2.2 G's on a 275 DR. If these new tires are lets say 255 I would think a min of 1.95 G's. So just a WAG for the 632. 60 Foot ET = 1.2241 330 Foot ET = 3.4843 1/8 Mile ET = 5.4284 1/8 Mile MPH = 126.1316 1000 Foot ET = 7.1115 1/4 Mile ET = 8.5372 1/4 Mile MPH = 158.1890 Stan Last edited by Stan Weiss; 01-28-2023 at 01:34 PM.

01-28-2023, 03:52 PM	#8
bigshow2966 Senior Member Join Date: Mar 2007 Location: chicago Posts: 616 Likes: 390 Liked 81 Times in 35 Posts	Re: COPO, Drag-Pak, CJ II, (FX) Secrets Geoff Turk is really covering the build of his BlackbirdX on Facebook. He hasn't put pedals in it yet, but has started the motor. I would guess his is DBW. They are on a 10.5 tire.

01-28-2023, 07:28 PM	#9
Keith 944 VIP Member Join Date: Feb 2006 Location: Dela-where? Posts: 2,116 Likes: 1,004 Liked 1,649 Times in 521 Posts	Re: COPO, Drag-Pak, CJ II, (FX) Secrets i know jack has nothing to hide as i have seen him blow the tires off many times, however i have been watching a blue cobra jet that leaves like a four cyl. and come alive like a banshee going down track, so if its allowed, dbw, percentage is prob. whats happening, it seemed much more likely than just pulling timing, but is more than certain some form of traction control and from what i saw, it was deadly.... __________________ KEITH MAYERS 2 X somebody many X nobody

01-29-2023, 01:06 AM	#10
GUMP VIP Member Join Date: May 2002 Location: Shelby, NC Posts: 1,665 Likes: 1,709 Liked 1,732 Times in 418 Posts	Re: COPO, Drag-Pak, CJ II, (FX) Secrets It really doesn't make a lot of sense to take the throttle out. Modern ECU's have almost infinite control of timing. Shocks, tires, and gearing might want to be added into the equation when trying to figure out what makes the supercharged cars work so well? I can tell you that every COPO that I have campaigned has run without limiting the throttle by anything other than the drivers foot. __________________ Daren Poole-Adams NHRA Stock/SS 2007 Last edited by GUMP; 01-29-2023 at 01:11 AM.