Update form my intro post about 1971 prostock


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Mike Bunch

New member
Feb 15, 2016
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My Car
1971 Prostock Nostalgia Dragster
I purchased a never completed 1971 prostock race car roller that had not been touched since 1970. Its a real ford body in white and appears to be a factory sponsored car.

I found the paperwork for motor work done from Paul Machine in Jupiter Florida from 1970 and tracked down the man who owned the shop who is known on 7173 as Paul of mo and he still had the motor so I was able to buy a vintage boss 351 prostock that was built with all of the best tricks and mods of the days. I have talked more to Mr. Paul in the last few weeks. He did not sell the engine because rules changed and Ford droped out of draagracing in 72. He said the engine was an experiment and he couldn’t sell it. Heres why.

The crank is stroked for 6 of the 8 rods. In the car the tech inspection could really only check the front 2 sparkplug holes for the stroke. The more cubic inches the motor had the bigger the weight penalties.

The distributer is a one of a kind homemade part that does not work like anyother dist and it does not have a limit to how fast it can work.

The heads have port plates and intake side stuffers with titanium valves and springs. The block is all rerouted for the oil and has lines running everywhere. It also has been set up for a vacume pump system to take the pressure out of the engine for more hp.

It has a homemade tunnel ram that was made to fake a weiand but works above 10000rpm.

New stuff,

We discovered that the bottom of the intake that covers the valley had 2 parts and was hollow inside with a passage cast into it that runs up to a intake bolt hole?? We found another port inside that had a tiny pressure valve in it but did not go anywhere?? I called Mr. Paul and this is what he told me.

1 of the intake studs was hollow and had a hole in it that lined up with the hole in the intake. You could screw a line onto the top of the bolt and pump nitrous into the manifold. The other valve could be shimmed to open at about 450 pounds. You filled the intake to about 400 pounds when the motor was cold. When the temp went up then the pressure in the chamber went up with it and once it hit 550 it would open the valve and let the gas flow threw very small wire drilled passages that runs to each intake port. It took about 2 min for the gas to go out. That would be long enough to do a burn out get set up and make a pass before there was no more gas left. The holes are so tiny that you can not even see them in the rough texture inside the runners. The relief valve is so small and hidden that you would not notice it even if you figured out there was a hidden chamber in the intake. We pumped it up with our compressor and at 500 it started hissing and at 50 there was the tiniest little tick sound and the hissing ended. There are no parts to it that can be seen and only one moving part.

Mr. Paul said that others would catch on and waste as much time getting ready to race to let the other guys gas run out. He called this burning them down. I looked this up and it was common to see this happen in the 70s and 80s. He said once it was figured out everyone who did this had to come up with something different.

With instructions from Mr. Paul we are replacing the rods and pistons with arias set ups 2 ford and 6 chyslers and will drop the compression to 12 to 1 and we are swapping out the distributor with a new msd. The tunnel ram had tops for 2 kindig box carbs. These were early preditor style carbs so we are going to try to get that set up running. He says we should have an easy 750hp without the gas and over 800 with it. We get the rods and crank back from the machine shop in a few weeks and then will get it all put back together. We are getting help from a local racer who builds 351 based racecars he thinks this is the coolest thing he has ever seen.

We are still figuring out what the car is and who may have been building it but are hitting dead ends. Once we get more details I will post pictures and are certain we own it free and clear.

Sounds like the typical racer of the day. Whoever cheats the most and gets by wins. This has gone on forever. Back when we circle track raced flatheads the tear down rules said to pull the head on the right bank and measure the #1 cylinder. You were limited to .080" over bore and stock stroke so you did that one cylinder .080" and the rest were .1875" over.

Even when we cart raced we cheated and got through national tech inspections. They never did catch one of my tricks that I will not disclose. The guy I worked for in the race shop said his brother never raced a completely to the rules car and he was 7 time national champion in NASCAR Sportsman, Iron Man Jack Ingram. He is now in the NASCAR hall of fame.

If you remember back in the Boss 429 days Ford had I think three factory cars on the strip. One went to England of all places and I know the guy that bought that car and sold again. Anyway the cars were said to be factory stock, lol. All four shocks were of different ratios so the car lifted even and transferred the weight to the rear. Front end pieces were lightened in areas you could not see and to get the weight on the rear they had Brass louvers on the rear window instead of aluminum. There was little on the cars stock.


If you want to get a little boost and not get caught you can grind your rings down in a special clamp fixture so they fit loosely. It will smoke like going to blow. But the key is you add nitro to the oil and it is pulled into the chamber bypassing the rings. Yes compression leaks but the gain from the nitro more than offset the loss. When they caught on to this one they would pull a sample of oil and pass a propane torch over it and it if burned your were disqualified. They started out checking before you went on the track but guys got smart and added a small pump from windshield washer to pump the nitro in after the tech inspection. So they started doing after the race.

Racers are good at pushing the rules. No nitro in the fuel and no injectors either. If you can gain 5 hp over everyone else then you win.

There is a rumor out now that some NASCAR guys have a remote control that will turn an internal part in the roll bar frame structure that either stiffens the chassis or loosens it. The only way to see is X-ray and they have not done that yet. You could vary for every turn if you want. Ever wonder how someone can win so much and other cannot.

Those were fun years in the 60's and 70's and Mr. Paul was in the thick of it for sure.

Keep updates coming I love this. Check the metal thickness on the front end parts see if factory put in thin material or acid dipped. When you have factory backing it opened lots of doors.



Do not use that intake that way - it will blow up and put your eye out or worse.

The underside of the base plate is thinner and our thinking was that if it failed it would blow out into the lifter valley and stay contained. Pressurizing it loose on a bench is just asking to launch it through your ceiling. The internal relief valve usually does not reset itself and one has to know the magic spot to smack the intake with a hammer to get it to snap back closed.

I have an intake that we built about the same time and for the same people. I will send it to you. You could probably actually use this one.


We built a doubled walled tunnel ram that from the outside looked like it had massive 4 inch wide runners but inside the runner width was more normal.

Between them was a void that could be filled with just under a liter nitro methane.

Like our nitrous oxide intakes it has wire drilled passages from the void into the bottom of each intake runner. These openings were very small and extremely well hidden in the normal texture of a cast intake. At the top of the carburetor plate is a inconspicuous core plug.

We had an assortment of core plugs with an ever increasing metering orifice drilled through them. With a solid plug no nitro methane could be pulled out. The smallest orifice would meter about 5% nitro methane and the largest would allow 20% nitro methane. We cast it with a well known brand name and with a part number that they had stopped selling a few years earlier.

This was certainly used and was never caught. It rapidly fell out of use when officials announced that they knew that "enhanced fuel" was being used - they were not exactly sure how - but they would soon have a way of testing the exhaust gasses and could measure as little as 1% burnt nitro methane during actual competition. I was told that several teams basically agreed to a truce. I do know for sure as I was not directly involved but from that time forward enhanced fuel was never used again. Strangely, other rules were relaxed at that same time but the elapsed times and speeds did not get better. More strangely, they seemed to actually drop off a bit for awhile next season. How odd.

In the 80's I came across one of these intakes at an auction. The seller said the gap between the inside and the outside was to help keep the fuel colder. It had our smallest metering plug in it but with it's center filled with epoxy. I bet they had fun finding that vacuum leak. I bought it for 100 bucks and put it on a shelf - it is on it's way as soon as I finish drilling out an assortment of core plugs for you.

I have recently talked to the one and only person that is still around and that worked with us. Oddly enough he is the only one I know for certain that did not overtly cheat while still managing to win just about everything. I am glad this happened or I would not have had that conversation with him.

We concluded that everyone we worked with has passed - I will not share names or places out of respect for old friends but I will share more about what was done. It was suggested that somehow this is important. Either it is or it is not but we sure had fun back in the day.

My notebooks are headed off to a group that can do something with them and this conversation has been picked up by a NHRA/IHRA pro engine builders group and I have been ask to join and contribute to their conversation. They are having fun in these days and all I will say is somethings never change.

I no longer mind if you post pictures so please do.

- Paul of MO

defiantly would like to see some pictures of this cool old stuff.