Hot Air Turbo Regal Recipe
Kevin Burns
James Burns
"This information represents what worked for the author(s) with their combinations. It may not work for you. Be aware that anytime you increase the performance of your car you run the risk of damage. Be smart about modifications: take them one at a time and keep a close eye on vital tuning indicators such as knock counts, O2 volts and RPM. This Recipe assumes you are using adequate octane RACING fuel for best performance. -editor"
Here is my brother's and my build up for an 85 GN. First I'll mention that Its best to make each mod at a time, and I suspect that anyone who does this should achieve better results than we did due to the age of the engine (120k), the valve springs being original, and the injectors were rattling.

I suspect with a bit more fine tuning, you should pick up about .3/3mph over my runs, on the same tires. When retired back in 95, the car had over 122 quarter mile passes, picked up 11.4mph and over a 2 second drop in ETs. I think with proper scanning equipment, faster results could have been achieved.

The Recipe
  • Magnecor wires 8mm.
  • NGK UR5 plugs (#2771)
  • 235-60-15 BFG Radial TAs (in back) (inital runs were on 215-65, look for 235 introduction)
  • Fuel Pump was from a GNX (original had failed)
  • Coolant Lines blocked off to throttle body.
  • Oil tube replaced with K&N Breather








Stock w/ KB Air Filter 3652 75 2.3 15.48/ 89.83 30 Idle
Gutted Muffler, KB Ultimate Chip 3650 60 2.0 14.71/ 94.15 70 .
Posi installed from 79TA(scrapyard 3654 57 1.99 14.31/ 93.02 215 0psi
Flowmaster X-flow Exh, 237 f. regulator 3653 73 2.05 14.26/ 94.59 400 .
Gutted Cat, Clutch Switch 3660 77 14.20/ 96.71 0
Used 26x10 Slicks, GNX O2 sensor 3650 75 1.98 14.07/ 97.31 88 2psi
Dial installed-boost 19psi (in BG, KY) 3672 80 1.87 13.63/ 99.48 15
Sway Bar& Driver Shock removed, Ram Air Hose, spare and jack removed, air bag 3581 85 1.98 13.59/ 100.75 40 8psi
Back in S. Florida 3580 74 1.82 13.53/ 99.81 0 7psi
Boost 20psi, Hoosiers, Southsides
13.52/ 99.63
Black Magic Elec. Fan
82 13.45/ 100.36 167
S10 whl cyl, steel drums, drag shocks, New Slicks on 8.5 rims (spares) 3630 77 1.77 13.46/ 99.53 250 9psi
Alum Drums, Art Carr shift kit, 87 Servo, Custom (tight) 9in Conv 3610 55 1.77 13.53/ 96.33 1350 2psi
Factory D5 stalled to 2500, BROKEN motor and trans mounts 3585 72 1.83 13.45/ 99.78 250 7psi
New Mounts, Factory 87 Cat & Convertor installed (modified), 235-60-15 Radial TA 3681 69 1.82 13.33/ 100.96 135 3psi
Conley Mag 4 (borrowed) 3591 82 1.88 13.31/ 101.23 0 2psi
Boost set to 15psi
13.50/ 100.53

Getting Started
Thats it. Unfortunately, I do not have very complete records, and we did not record when we were running which types of gas, but the car ran SLOWER with leaded fuel as opposed to 93 or 100 leaded, with the final runs being made on 93 octane and a bottle of black 104 octane booster (now out dated stuff).

[Editor's note - with the boost levels being run in this Recipe, it is highly recomended you use more octane than this, especially on a nonintercooled car]

I think you can see that the 9in hurt the cars performance, and I don't have the same day comparison of slicks vs radials, but I assure you the radials were faster.

I tested a custom built turbo, similar to a ta49, but the car did not like it, and I had major spooling issues, even with the 9in. Similarly, you may have different results, on another car. That same turbo and an Art Carr 9in shredded its tires from off idle through 3rd gear with a motor knock. No track results though.

Other mods. that hurt the performance were an XP pump (too much fuel) and a fuel enhancer (also too much) though not at the same time, each of these modifications hurt the cars performance over the stock (if applicable) parts.

[Editor's note - with new adjustable fuel pressure regulators, it is advisable to have excess fuel capacity and use the regulator to cut down on fuel delivery]

  • Modify the inlet adaptor between the turbo and intake, to recieve the turbo, rather than sit inside of it.
  • Intake and head work (but workedto enhance torque, not just HP)
  • TA48 style turbo
  • Improve exhaust with an ATR system
  • 2 1/2 dwnpipe (mandrel bent)
  • Custom Chip with new stock injectors (or flowed)

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