Automotive Forums .com - the leading automotive community online! Automotive Forums .com - the leading automotive community online!
Automotive Forums .com - the leading automotive community online! 
Latest | 0 Rplys
Go Back   Automotive Forums .com Car Chat > Panoz > GTRA / GTWS / GTS
Reply Show Printable Version Show Printable Version | Email this Page Email this Page | Subscription Subscribe to this Thread
Thread Tools Search this Thread
Old 04-25-2022, 05:21 PM   #1
Steve Hummel
AF Newbie
Join Date: Aug 2016
Location: Petersburg
Posts: 13
Thanks: 0
Thanked 0 Times in 0 Posts
Sharing Upgrade Specifications

We run our Panoz GTS in VARAC's CL-A vintage racing class (fastest full bodied cars). We were fortunate to win the 2021 points championship in the car (chassis #50). I am 65 years old so no "spring chicken". I must say that Panoz did a real nice job with these cars.

We run a wet sump SB Ford 351W with hydraulic roller camshaft & Shell 91 pump fuel. I have not included specifications on our current engine as we have run 3 different engines in the car. Anyone that wants to know what we have run & what has worked best can contact me @

Our current engine makes 634hp @ 6,200rpm & 646ft-lbs of torque @ 4,700rpm. This is not the most powerful motor that we have run in the car. Again, we use Shell 91 pump fuel exclusively (no ethanol) & hydraulic roller cams. We change valve springs once per year & oil once per year, that is it! Our engines have a "few" tricks given the background in the "Note" below.

We have made a large number of technical improvements to the chassis & I thought that I would share those with the Panoz community. We really love our car! I have shared photos with some of our forum members, no problem sharing what you need.

I bought it in 2016 from 2nd owner, took a year to rebuild it to our specification (car was good & running when I bought it but it is that "engineering" disease that myself & my team have). We started racing it in 2018, it has done very well, podiuming almost 75% of the time.

We just finished our mandatory tech inspection for the 2022 racing season (no issues) & we will be hitting the track on May 7-8.

Vehicle Improvements:
· Note
o Vehicle improvements were implemented based upon over 40 years of road racing experience of the owner as a driver, team owner & engineer (1st company was a racing cylinder head engineering firm, did work for Big 3 & HD at highest levels of professional competition, former GT-1 champion, just retired from 15 years with Porsche in Stuttgart, raced one of those but not my real love so I went back to what I love, NA V-8's, much better engineer than driver though). Notable & high quality outside resources were also used to develop & execute the improvements. My "old guy" volunteer crew is full of T/A veterans.
· Front Suspension
o Upper ball joint relocated 7/8” rearward for superior caster performance & bump steer (determined during computer modeled suspension simulation)
o Steering arm re-engineered to double versus single shear design for safety
o Tie rods bump steered to 0.018” of bump steer through 5” of suspension travel
o Steering components all safety wired
o Lower control arm inner rod end increased in size to reflect higher G-loading due to front tire size increase from OEM 275 to 295 (fits under OEM body)
o Upper Control Arm (UCA) camber adjustment is now a captured adjustment system in horizontal plane to prevent UCA movement under high G turns, allows for squaring, offset & camber/caster fine adjustment (car could turn hard enough to cause OEM design to move)
o Steering rack by AGR (Mustang rack & pinion), AN-6 fittings for increased flow, Cobra R valving, Moog tie-rods, no limiters installed as nylon spacers fail under racing conditions (tire steering angle limited by lower control arm strut), plumbed with AN-6 power steering hose for high pressure lines & stainless for low pressure lines
o KRC racing power steering pump replaces OEM Ford pump (lighter & easily adjustable)
o Adjustable front sway bar links to neutralize preload (OEM were not easily adjustable)
o Rear trailing lower control arms had hex flats welded on to facilitate proper tightening of rod ends
o Penske shocks rebuilt & dyno’d (in 2017 & again at the beginning of 2022)
o All new rod ends installed upon rebuild & checked before every event
o Front sway bar mount moved down 1/8” for additional oil pan clearance
· Rear Suspension
o 4 link bars & Watts link bars were fabricated from chromoly steel versus the OEM aluminum bars
o Cast iron 9” pot replaced with Strange Engineering aluminum 9” pot
o Strange pot machined for NASCAR pinion driven rear end lubrication pump & rear end cooler
o 4” long rear wheel studs, bull-nosed by F+F (OEM studs short & not bull-nosed)
o Ό” aluminum spacer added to driver side rear hub to correct rear geometry to perfect square rear footprint
o Rear 4-link control arm fabricated spacers on axle to square arms to chassis & axle
o Droop limiters installed on chassis to prevent damage to rear shocks when rear end is unloaded
o Penske shocks had main bodies replaced, rebuilt & dyno’d (2017 & 2022)
· Chassis
o OEM rectangular top front cross bar replaced with triangulated chromoly tubes (removable) to increase front chassis stiffness due to wider front tires
o Oil cooler mount installed ½ way between upper & lower front chassis cross members to prevent front chassis flex with wider front tires
o Accelerator pedal modified for improved heel/toeing
o Throttle shaft to carburetor has square adjustment section welded in to facilitate proper tightening of rod ends
o Kirkey aluminum racing seat with cloth cover
o Fabricated aluminum top seat mount (weight reduction)
o Fabricated aluminum tube rear bumper bar replaces heavy steel tube bumper bar (OEM)
o Racing style safety latch on window net versus OEM seatbelt latch
o G-Force window net with new lower straps
o Polyurethane rear transmission mount
o Polyurethane engine mounts
o High strength driveshaft u-joints
o Square jacking point receivers welded to chassis in place of OEM round receivers, square receivers are safer in that the jacking post insert will not rotate
o Fabricated hollow chromoly shift rod replaces solid steel rod (lighter)
o Shifter to shift rod mount sleeved to minimize horizontal play of OEM configuration
o Shifter eyeball replaced & solid capture eyeball retainer fabricated to minimize vertical play of OEM mount retained by snap ring
o OEM steel transmission cover replaced with 2-piece aluminum cover retained by Dzus fasteners to reduce weight & facilitate easier removal & installation of transmission cover
o OEM switch panel refabricated with lightweight carbon fiber
o Transmission cooler & pump installed to improve transmission durability
o Transmission aluminum breather tank installed (OEM chassis depended upon vent on transmission)
o Fuel cell foam replaced in 2021
o OEM air-to-oil engine cooler replaced with oil-to-coolant engine oil cooler plumbed behind front of chassis (minimize crash damage & more efficient that air-to-oil coolers plus reduces engine wear from cold starts)
o 75% larger aluminum engine coolant radiator installed with power steering cooler in driver side tank
o Single engine radiator cooling fan replaced by twin 12” fans
o All radiator hoses replaced with high pressure silicon hoses
o OEM Ford coolant overflow plastic tank replaced by smaller aluminum tank with an accompanying aluminum catch tank
o OEM rear view mirror replaced with 5 panel Wink mirror
o 3-quart engine oil accumulator installed with remote activation cable to prevent engine oil starvation under high G forces
o Fuel cell dipstick installed to properly measure fuel in the fuel cell
o Fabricated ceramic coated 2” long tube headers with merge collectors & 3.5” stainless secondary pipes installed in chassis to replace OEM Hedman shorty headers & 2.5” exhaust (headers were designed with PipeMax, standard professional exhaust design software)
o Removable 3.5” i.d. stainless steel racing mufflers versus OEM fixed large 2.5” mufflers
o Fuel pump rebuilt with all new components
o Cleanable fuel, transmission & rear end filters installed
o NASCAR large external engine oil filter & housing installed
o Large twin filter engine oil breather system installed
o All new AN fuel & oil lines installed
o Air cleaner has ½” taller K&N air filter versus OEM K&N with a K&N filter top
o Profiled aluminum air cleaner base versus OEM steel angled base to improve carburetor flow
o Air box modified to fit inside of additional rear hood pins
o Body:
o OEM Morflex front air dam replaced with removable aluminum undertray with splitter that minimizes air flow under the chassis & encourages air flow over the hood
o CFD (Computational Fluid Dynamics) data was used to install 4 hood vents (2 on hood sides fabricated from aluminum & steel mesh, 2 on hood top fabricated from carbon fiber) to evacuate air from under hood to improve cooling & downforce
o Using same CFD data the rear wing was moved back 5.50” & raised 3.75” to improve efficiency
o A 0.210” high Gurney flap was designed & attached to the rear top of the win to generate approximately 20% more downforce with only a 2% increase in drag
o Wing mounts triangulated for improved rigidity
o OEM wing mounts were not adjustable in terms of angle of attack, new wing mounts are adjustable in terms of angle of attack
o 3mm Lexan rear window replaces Ό” thick OEM Lexan unit
o OEM SN95 Mustang glass front windshield replaced with Optic Armour Lexan windshield
o 3 Aluminum windshield braces installed to support the inside of the Lexan windshield
o OEM Ford electrically adjustable side mirrors replaced with smaller carbon fiber formula car mirrors
o Carbon fiber side mirror mounts
o Hood pinned in 4 places in rear to retain body shape & hood at high speeds
o 4 Dzus fasteners added to leading edge of hood to better retain hood at high speed
o Lightened door hinges & aluminum mounting blocks
o Ό turn Dzus “winged” trunk mounts replace OEM threaded mounts
o Larger aluminum protective body plates at exhaust outlets
· Electrical
o Powermaster racing alternator versus OEM Ford (lighter)
o 10 circuit modern blade fuse box with LED indicators replaces OEM unit
o Motorola CM300 2-way radio & helmet harness with steering wheel talk switch
o Roof mounted blade antenna for 2-way radio
o Autometer low oil pressure light with LED bulb
o Ford OEM TransAm fuel pump safety G-switch, resettable
o Dash fabricated with aluminum & carbon fiber, all new switches & LED indicating lights with professional labels
o Exterior electrical cutoff switch labelled with safety orange plate & professional labels
o Radio EFI filter
o MyLaps transponder
o LED rear brake & rain lights
o Lightweight Autometer oil pressure, oil temperature & water temperature gauges
o Optima yellow racing battery replaces OEM battery
o MSD 6AL ignition box, modified with Weatherpak connectors
o MSD Pro-Billet distributor with large diameter cap assembly
o Taylor coil & spark plug wires
· New wiring harness fabricated with thermo insulation
· AiM EVO4S data system with SmartyCam & relevant sensors including GPS antenna
· Brakes
o Brembo calipers rebuilt, red paint stripped, re-coated black, new Brembo labels
o New Brembo discs installed, Coleman made all our spares

o SS flex lines installed on all 4 wheels
o Tilton master cylinders installed
o Bias adjustment mechanism rebuilt to correct bent control rods
o Hawk brake pads
o Driver side rear caliper shimmed inward to correct clearance issue, caliper also moved towards axle centerline to improve pad coverage
· Wheels/Tires:
o 9.5” front OEM BBS wheels for dry racing, powder coated black
o 11” CCW rear wheels for dry racing, powder coated black
o 9.5” OEM BBS wheels for wet racing, powder coated black
o 315/30/18 Hoosier road race radial rear tires versus OEM 285/18 Pirelli
o 295/30/18 Hoosier road race radial front tires versus OEM 285/18 Pirelli
· Transmission:
o Tremec TKX 5 speed transmission replaces TKO 5 speed transmission for 2021
o Rebuilt OEM OEM TKO600 in 2017 with all Liberty transmission modifications, broke transmission cases in 2018, 2019 & 2020 due to engine torque
o No issues with TKX transmission in 2021
o Tilton clutch master cylinder
o Tilton hydraulic release bearing with hose capture to prevent hoses rubbing against clutch
o 2-disc 8.25” Quartermaster Extreme-V clutch replaces OEM single 8.5” clutch
o Bellhousing indexed to centerline of transmission input shaft
o ARP crankshaft flywheel bolts
o Tilton 6000 series hydraulic release bearing, rebuilt with new lines in 2022
o New clutch hydraulic release bearing lines to master cylinder in 2018


519 572 seven six five four
Steve Hummel is offline   Reply With Quote
Old 04-26-2022, 08:01 AM   #2
AF Newbie
Join Date: Sep 2021
Location: Saint Louis
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Sharing Upgrade Specifications

Thanks Steve Great Stuff

Chris Lorenz
teamlorenz is offline   Reply With Quote
Old 04-26-2022, 09:01 AM   #3
Steve Hummel
AF Newbie
Thread starter
Join Date: Aug 2016
Location: Petersburg
Posts: 13
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Sharing Upgrade Specifications

No prob Chris. Racing is a team sport.

I posted a short video on YouTube of 3 2020 events. I have not had the time to edit the 2021 events as I am restoring a 1965 vintage road race notchback Mustang. I have edited "snippets" from these races, we did pretty well.

The engine for our 2020 season was the original Panoz 351W Ford block, +0.030", with a 4" stroke, wet sump, AFR 195cc heads, Comp Cams #35-427-8 hydraulic roller split pattern camshaft with Jesel 1.7 shaft rockers, Victor Jr. with a 1" HVH 4 hole spacer, 9.4:1 compression, 750cfm Holley TransAm carb, & the original Hedman shorty headers with the 1 5/8" step removed, replaced with 1 3/4" & Coleman merge collectors to a 3" straight pipe. We ran Shell 91 pump gas all season. This engine made 611hp @ 6,000rpm with 28 deg total timing. We do a lot of dyno testing to make sure that we get the most out of our equipment because most of our competitors are running much lighter cars, with dry sump systems, high compression & solid roller &/or overhead cams.

Our fields have between 35-50+ cars in the VARAC Classic field. I am not a great driver who can perform "hero" laps so I rarely qualify on the pole but usually in the top 4. We podium about 75% of the time. At age 65 I rely on consistency & experience plus a well-prepared car by a veteran crew.

Any Panoz owner knows that these cars are really well engineered & hence very consistent on the track. Compared to running a GT-1/TA car racing a Panoz is incredibly cheap yet very competitive, especially if you focus on engine torque versus hp.
Steve Hummel is offline   Reply With Quote


Go Back   Automotive Forums .com Car Chat > Panoz > GTRA / GTWS / GTS

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

All times are GMT -5. The time now is 04:18 AM.

Community Participation Guidelines | How to use your User Control Panel

Powered by: vBulletin | Copyright Jelsoft Enterprises Ltd.
no new posts