DoctorLarry

It uses a metal plate and foam element to seal against the hood-it does not use the normal cowl intake setup. The 73 Grand Am had two NACA ducts in the hood that could be opened up for a factory ram air setup (although the EPA nixed it because of noise levels). The car used the hood ducts for fresh air rather than the usual cowl setup, which raised a few eyebrows among the NASCAR tech inspectors.

Not much time lately on this but a few things done. I scratch built an intake from a Chevy NASCAR engine base and mounted the resin Holley Dominator I found. Stripped the chrome from the valve covers and drilled the engine for plug wires as well as a distributor. Plumbed the braided fuel line for the carb. Added roll bar padding and started to mock up the engine. Added the braided lines to the remote oil filters and drilled the valve covers for the vent lines back to the oil tank.

I do them occasionally when I have some spare time.

They also had installed mesh over the front grilles in this photo. I lived 18 miles from the Daytona track for 21 years and went to a few races. The amount of sand and other debris kicked up in a race at those speeds is pretty substantial. If you walk near the track during a race you feel like you are being sandblasted when the cars go by.

The Petersen archives photos show a racing seat like this with a fabric cover-may have been Corbeau but clearly not the usual NASCAR.

Harry, are you harryquackenboss on Linked In? Just wondering. Thanks for the kind words. I love the Collonade Pontiacs and have owned three Collonade GM cars. I also resin cast Pontiac scale cars and have always wanted to build the 73 Grand Am. With your help and Mike's as well as the Petersen archives, this project became a reality and it is a blast.

Very nice-you guys are detail masters.

The Motor Trend story referenced the chrome wheels. Evidently chroming caused hydrogen embrittlement on the wheels and they were indeed heat treated afterward to eliminate that. My opinion is that you are correct. Those really look like Spyders to me. The Motor Trend story also said that the wheels flexed so much that one of the bleeder screws on a caliper was ground off causing a brake pressure loss that they had to fix.

This was from a Martyn Schorr book about Pontiacs-section on an engineering prototype Adams put together at Pontiac. They reference Kelsey Hayes supplying the wheels which look almost exactly like the Motor Wheels. Did the team ever test them on the Grand Am? It sure looks like it in that photo I posted.

I read somewhere else that for a test version of a Firebird they had at Pontiac that Kelsey Hayes supplied the wheels which looked a lot like Motor Wheel. Did the Tempest use Minilites for weight or because the team was paying for their own parts?

After much new information from Mike and Harry Quackenboss about the Adams project cars, I resumed trying to replicate the original as closely as possible. I added the kick panel portions of the firewall and scratch built the oil tank, oil cooler, remote oil filter unit and radiator puke tank. I put in the braided lines and fittings. Front suspension is in and I added the front shocks and braces to the frame. I built heim ends for the front sway bar but it was too close to the engine so I have to re-do the bar, which mounts on top (rather than bottom) of the frame. Mounted the differential oil cooler and pump. I found a resin low back racing seat like the original. The real car had a snap on fabric cover for the seat and I found some similar looking craft ribbon to make that out of. Bracket for the seat mount and harness mount is in as well as a small switch bracket on the floor. I found a fire extinguisher and made the straps that hold it in. Harry said that it used a truck arm rear suspension because NASCAR required it. He actually called Herb Adams to verify! (big thanks for that one!) Now it needs fuel and brake lines, calipers and rotors and detailing the engine. The car is hard to replicate because everything was painted black! I am scratch building an intake (already made the valley pan) and I found a resin Holley Dominator. Modified the block for the dry sump lines (Thanks again Mike and Harry) and so I am getting close. radiator is ready to go in as well (I had to modify the core support to get it right). I feel like Dave Van here-I don't want to think how much this has cost but it sure is fun to replicate such a beautiful car. At least if I screw the body up I can always make more of those...

Another question relating to all three cars: The Gray Ghost ran Minilites on it in all of the photos of the car. I assume that they never used anything different on it. Photos of the Minter Firebird show it with Motor Wheel Spyders on it. Some of the Petersen photos of the Grand Am appear to show it running Spyder wheels on it. Did that happen or is it just the way the photos look? The photos of it sitting still show the 5 hole Nascar type wheels but the motion photos look different to me. If you blow this up the wheels look a lot like Motor Wheel.

Hopefully this has not been an exercise in answering repeated questions from pestering students.....

Do you know if they used a Watts linkage or Panhard bar to control side movement?

Thanks, Harry. I was going with the 4 link but now I can do it more accurately! I That was where I started before I saw the Petersen archive photos and read all of your comments. I can finish my chassis up now. Thanks again-we have really put you out for a couple of models! Larry

Harry-any thoughts come to mind on the Grand Am rear suspension?

Great. Thanks, Harry! LB

Check out the parallel Team Associates Grand Am thread on the NASCAR board-Mike has posted the modified rear suspension photo that shows the modified mounts on the rear axle for camber changes.

If you look at this, neither the upper or lower control arm mounting positions have been altered. The upper arms are steel tubing with spherical rod ends but the lowers are stock with a stock sway bar and mounted in the stock locations. The team must have altered the geometry later to improve handling. With the altered lower mounts I doubt the stock sway bar would have fit anymore so they must have ditched it.

That nails it! Thanks, Mike. Harry-did the Grand Am use the same rear suspension setup as the Ghost? Mike has some really good shots of it and if Herb Adams used the same basic architecture I will have all I need to finish. Thanks, guys!

Good description of the pump on the SD 455 block, but no pictures of the outlet location: https://www.hemmings.com/magazine/mus/2008/08/The-Guts-Inside-the-Glory/1676887.html

is that near the oil filter? Is that the orange on the left side of the picture?

I found the hotrod.com article and saw pictures of the rear of the block area where the drive gears were for the pump. I just wondered whether the pump was visible from the outside of the engine or not. Now I know! Thanks, Harry.

Mike and Harry: Would you think that they used a similar dry sump pan on the 73 Grand Am? I can see the oil tank mounted in the same area on the grand Am as well as the remote cooler up front and dual remote filters. Any idea which side the dry sump pump would be on? I don't see a Gilmer belt on the engine photos on the Grand Am that would indicate a separate dry sump pump.

Went through the Petersen archives and pulled out a bunch of close ups. Revised the chassis around the stock frame (Revell 66 GTO). The frame is slightly different that the 73-77 cars so I had to shorten it 3 mm. Built the cage just like the pictures using one of my own resin firewalls and dashboards. Dash is pretty simple. Gauge bezels are thin slices of plastic tubing so I can Molotow chrome the rings and decal the faces. This is really a simpler build because it is pretty stock. I can see oil tank, cooler and remote filters but cannot see a dry sump pump or pan lines so that is still up in the air as well as rear suspension details.My Chassis Engineering book is supposed to be here shortly so maybe some ideas from that.