MuscleTang mod project thread (1971 M-Mach 1)

[tony-muscle]

As I am planning my work for this winter I will start updating this thread.

First of all I want to give some feedback on the Panhard bar. This is one of the best suspension upgrades I have done. Granted that all goes in concert and by itself it may not provide such a difference than as part of the combo. The Panhard bar has definitely planted the rear end during hard cornering. During Autocross, oversteer is a lot more difficult than before. You can feel as you are approaching oversteer better, so it becomes a lot easier to control. This has made the car a lot more fun to drive hard. After a whole year of about 30-40 autocross runs I am still working on driving the car to the limits. I did not have any wipeouts this year but I know a couple of times I chickened out and decided it was better to hit a cone. I think I still can push the car a little more, but it is that balance between safety and driving at 95%. The good thing is that in Autocross, most of times, a wipeout just means hitting a few cones. However, there are some instances where there are curbs and concrete walls where I definitely take it more easy.

 

[tony-muscle]

As for mid year issues, here it goes (ongoing posting)

1) Oil pressure
I have some oil "starvation" in hard cornering and braking, but thanks to the Accusump the engine does well. That said I am working on getting a custom made oil pan from Kevco specifically for road racing. Their racing oil pan, which I have, is better for 1/4 mile racing where acceleration is more prevalent. Once I install the custom pan I will be selling mine. The reason I know of the oil starvation is that I have a light that turns on when the Accusump kicks in, which is when the oil pressure goes under 35 psi as measured in the oil port next to the filter. Previous measurements show that this port typically runs about 10 psi higher than the port at the rear of the engine where the oil pressure sender connects. That said it is not complete starvation, but definitely lower pressure than normal.

2) Fuel starvation
Since I have an electric sump pump that holds about 1 quart of gasoline, the issue is not the fuel slushing on the fuel tank. I have been dealing with it for about a year so I have tested different things. I upgraded to a Robbmc mechanical pump to increase the flowrate of gasoline and this definitely improved matters in shorter circuits, but I still had fuel starvation at Road America's straightaways. The front straight is about 3/4 of a mile long so you are flooring the gas pedal for a while. After talking with Rob he suggested that his sump pump is designed more for ¼ mile where the fuel use is less than on a long track. The sump pump has a restrictor hole on the inlet to limit the amount of fuel in so it works with the specified ¼” return line. Since I have a 3/8” return line, he suggested I could drill the restrictor to increase its diameter. This involved disassembly of the sum pump so I took the opportunity to upgrade the internal electric pump to one that could handle more than 500 hp – my next upgrade will likely take me over that hump.

 

[tony-muscle]

3) Engine oil catch can
This has a long story behind it. I first had an adjustable PCV valve but I knew that too much oil was being sucked from the valve covers. I added a catch can and proved that theory. This led me to eliminate the PCV and just add breathers. This led to oil seeping through the breathers and making a mess. Eventually I decided to add a custom-made catch can with breathers. This was the solution! No more oil mess and after a few races I have not seen any oil in the catch can either.
As you can see in the picture I have the breather hoses connected to the rear of the valve cover. There is a third breather on the front driver side but this is mainly there as a oil fill cap. This breather is partially clogged with ScotchBrite. Besides the hoses from the valve cover I also have a breather hose from the oil pan to the catch can.
PS: the catch can is custom made to fit in the only place I had at the rear and higher than the valve covers. I made it out of 2.5" square tubing and located the breathers in between the shock tower brace and just clear of the air filter plenum. I welded my own baffling inside the can.

 

[tony-muscle]

As for mid year issues, here it goes (ongoing posting)

1) Oil pressure
I have some oil "starvation" in hard cornering and braking, but thanks to the Accusump the engine does well. That said I am working on getting a custom made oil pan from Kevco specifically for road racing. Their racing oil pan, which I have, is better for 1/4 mile racing where acceleration is more prevalent. Once I install the custom pan I will be selling mine. The reason I know of the oil starvation is that I have a light that turns on when the Accusump kicks in, which is when the oil pressure goes under 35 psi as measured in the oil port next to the filter. Previous measurements show that this port typically runs about 10 psi higher than the port at the rear of the engine where the oil pressure sender connects. That said it is not complete starvation, but definitely lower pressure than normal.

So talking about oil pressure, I received the custom pan from Kevco. I also added a temperature sender port and a vent port just below the scraper.

 

[Cleveland Crush]

That's a nice pan Tony. What is your plan with plumbing and routing for the vent port?

 

[Kilgon]

Very nice looking pan. Do you plan on pulling the engine this winter or just raising it enough to get it on?

 

[tony-muscle]

That's a nice pan Tony. What is your plan with plumbing and routing for the vent port?

If you look at the picture on the previous post, you can see on the passenger side there is a "Y" fitting between the valve cover port and the catch can where the hose from the oil pan will connect to.
Edit: the Y fitting is hard to see since it is right under the brace tube.

 

[tony-muscle]

Very nice looking pan. Do you plan on pulling the engine this winter or just raising it enough to get it on?

I will try rising it enough and hope there is enough of a gap for this pan. I already did it with the stock pan that way but I am not sure if it will work with this one.

 

[tony-muscle]

Continuing with the mid year mods:

4) Rear axle oil mess
After each track day I was getting a lot of oil being spit through the rear axle breather. This made for a mess of oil over the rear axle, springs, shocks and exhaust pipe. This also caused the car to smoke as the oil over the exhaust pipe burnt. This has been going on for a while so I extended the breather hose to be right under the floor and then I increased the diameter of the hose. None of these made much of a difference. Although the oil level was below the fill plug the oil gets very hot and expands. Add to this the pressure generated at high speed makes the oil to overflow through the breather. It has never happened after prolonged driving in the highway, but it happened on track.
After asking around, the Mustang race guys at VMF suggested to add a catch can so the extra oil goes to the catch can at high speed and then drains back to the axle. They use catch cans mounted inside the trunk but I didn’t want to have it inside the “cabin”. With that I figured that there is some room between the gas tank and Panhard bar where I can fit one. I looked around in Amazon and bought a generic rectangular catch can (https://www.amazon.com/gp/product/B0BXC8R4VQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1). I still had to chop/reweld a corner to make sure it clears the axle. BTW, this was my first foray into welding aluminum. My welder already came with the handle reel so I just had to get the proper 100% argon gas. I also had to weld an extra bracket. From the catch can I have a hose that goes up to right under the floor with a breather. I had to replace the straight breather fitting from the axle with an angle fitting to keep the height below the catch can. I have not yet tested this new system on track but I hope it would work. I will now fill the axle oil right to the fill hole and hopefully any extra oil will be pushed up to the catch can. The location on front of the gas tank is just a bit higher that the rear axle so most of the oil should drain back as the car slows down.

Picture taken from on front of rear axle towards rear/driver side of car:

 

[Kilgon]

Learn something new every day. I can see that with the extra forces of racing and hard cornering it could force it out the vent. That is one of those things you would never think about and then when it happens you wonder what is going on. Just like any other fluid, it's going to expand when it gets hot it has to go somewhere. Nice job and I hope it works well for you.

 

[tony-muscle]

5) Rear axle bearings
It seems that AutoX and road racing was too much for the rear axle bearings to handle. They lasted about 10k miles before starting being noisy. Removal of the axles revealed that the bearing races/housings had cracked. I may have to get used to replacing them after every season or every other season as a preventive measurement maintenance. The ultimate solution would be going to full a floater type of Ford 9 where there will be two bearings holding a spindle. This is a costly option so not what I will be doing soon. Another temporary solutions is upgrading to big conical bearings but I was advised that these eventually fail as well.

 

[PoFoMoCo]

Tony - well done!! Thanks for the off season updates. I miss those days more than I like to admit…

 

[tony-muscle]

Learn something new every day. I can see that with the extra forces of racing and hard cornering it could force it out the vent. That is one of those things you would never think about and then when it happens you wonder what is going on. Just like any other fluid, it's going to expand when it gets hot it has to go somewhere. Nice job and I hope it works well for you.

Tell me about it. I am founding a lot of little issues on track that these systems were not designed to handle.
To give you an idea, last time I was on track and had the messy axle oil issue, I had filled oil up to about 1/2" below the fill hole. After seeing this mess under the car and while very hot, I removed the fill plug. At that point a lot of oil started pouring out like it was overfilled but it was not. When I got home, and the oil cold, the level was still reasonably below the fill plug. I will guess that the expansion gained about 1" or more of oil level. After some research I found out that oil could expand 7-8% for every 100C of temperature increase. Unfortunately I didn't measure the temperature of the axle but it was burning hot to the touch. However, oil still looks good and not cooking.

 

[Kilgon]

Tell me about it. I am founding a lot of little issues on track that these systems were not designed to handle.
To give you an idea, last time I was on track and had the messy axle oil issue, I had filled oil up to about 1/2" below the fill hole. After seeing this mess under the car and while very hot, I removed the fill plug. At that point a lot of oil started pouring out like it was overfilled but it was not. When I got home, and the oil cold, the level was still reasonably below the fill plug. I will guess that the expansion gained about 1" or more of oil level. After some research I found out that oil could expand 7-8% for every 100C of temperature increase. Unfortunately I didn't measure the temperature of the axle but it was burning hot to the touch. However, oil still looks good and not cooking.

It a shame our rear ends don't have covers. You could use one from Trick Flow or Banks to help dissipate the heat. Going out in left field but it be kind of neat to figure a way to hook up a cooler to it.

 

[tony-muscle]

6)Aerodynamics
So the last of the mods for this year includes aero work. As I have posted in another thread. I added a grill cover with the idea of redirecting the air that flows in between the radiator and hood through the radiator or to under the car. This involved adding a grill cover from MP Products. Unfortunately this cover does not fit well so I had to modify it extensively to fit. The hump in the middle for the hood lever does not allow the hood to close so I had to cut it. The ends had to be trimmed. I had to cut the area where the hood pins go (this is unique to the hoods with pin so I was no expecting the cover to have this feature). At the end I made it fit with a goal of function, not looks. I don’t recommend it if you are going for the looks due to the extensive cutting needed.
The other aero mod I did was to create an undercover from the front spoiler back to the strut rod cross member. This will help in redirecting more air under the car and smoothing the airflow underneath. My second iteration of this undercover involved a 1/8” ultra high molecular weight polyethylene sheet that I cut and heat formed to shape. The cover attaches to the lower lip of the front spoiler and to the underside of the strut rod cross member. The edges curve up and are attached to the fenders. It took some time to cut and mold to fit but overall I am very happy with how it turned out. You really have to know what you are looking for to really notice it.
My first version were made out of 0.100” ABS sheets. After my first track day of the year these were all cracked and useless. The UHMWPE sheets have lasted 3 track days since with no issues. They are not only thicker but this material is much more tough so it can take more abuse.
It is hard for me to say if they do something or hard for me to measure any improvements. Whatever they really do, at least I tried my best to improve the airflow under the car.
Over the winter I am taking the task to reinforce the attachment to the front spoiler since I think this is causing the vibrations I get as I approach 120 mph. I will be adding some bracketry extending from the bumper brackets to reinforce the center of the spoiler/undercover.

Grill cover after mods:



Undercover:

 

[BUCKWHEAT]

Unless you do open road track events, you should be just fine with your 2" rear drum brakes. Blow the extra cash elseware...???

 

[tony-muscle]

Unless you do open road track events, you should be just fine with your 2" rear drum brakes. Blow the extra cash elseware...???

I am confused about your post in relation to this thread. But just in case, I do track and autocross my car and I am very happy with my brake setup.

 

[PoFoMoCo]

Aero work is often ignored or over looked. I know I wasted a couple years without a splitter on the front of my 99 Cobra before I realized the cost was very negligible when compared to the overall speed, timing and safety it added to my car.

 

[AcesArneson]

5) Rear axle bearings
It seems that AutoX and road racing was too much for the rear axle bearings to handle. They lasted about 10k miles before starting being noisy. Removal of the axles revealed that the bearing races/housings had cracked. I may have to get used to replacing them after every season or every other season as a preventive measurement maintenance. The ultimate solution would be going to full a floater type of Ford 9 where there will be two bearings holding a spindle. This is a costly option so not what I will be doing soon. Another temporary solutions is upgrading to big conical bearings but I was advised that these eventually fail as well.

View attachment 83519View attachment 83518

 

[AcesArneson]

I wonder if perhaps your heat issues aren’t coming from your brakes. The facts that you are super-heating your gear fluid so high could be breaking it down and not protecting your bearings. I have seen some cars in Motorsport add baffles to force air into the middle of disk brakes to help heat flow through the internal vents and cool the brakes quicker. If you can get the heat away from your breaks you can prolong the life of your bearings.
Additionally do you find your brakes spongy after heating up? If your bearings are toast that same heat is also destroying your brake fluid. Lots of guys in motor cross will bleed their brakes and add new fluid between races to get rid of water in the brake fluid which impedes brake pressure.