Sunday, January 31, 2010

more on the Chuck Manning Special

Remember the Chuck Manning Special? We talked about it a couple of times last year. There are a lot of them around America although Chuck only built the original one. After it won the inaugural sports car race at Golden Gate Park, it achieved such notoriety that everybody else wanted one, mainly because of its rigis chassis design probably. Chuck responded to this by supplying plans to anyone who wrote to him and the rest is history. This car has the protruding upper lip that has been mentioned in posts on the Mark 7 with Nagari doors. Maybe that's where the idea came from. Since those Chuck Manning posts I have heard from the odd US citizen reminiscing about the cars, including Ron Dona, who worked with Chuck at Douglas Aircraft in the 50s where they became close friends. In 1958 the both left Douglas in El Segundo and went to Aerojet in Sacramento. Ron is very familiar with the Chuck Manning Special and its innovations and below are some of his recollections.
Re: An overveiw of Manning's car and innovations. Some of this was documented 60 years ago in Road and Track articles but here's what I recall.

Chassis: Chuck did not feel that his chassis was of great interest. The design criteria was to satisfy his torsional stiffness (TS) requirement at a low weight. He said that when TS was met the beam stiffness would OK and mild strength steel would be adequate. Calculations showed that a single four inch diameter tube with the right wall thickness would be preferred to the heaver double ladder design, but that tubing was not available at the company surplus metals yard. A side note of the chassis was that after winning the Palm Springs race the press asked Chuck if he would divulge his chassis design and he said "send me $2.00 and I'll send a copy of it". The response was so great with bags of envelops containing $2.00 in them that the postal service sent investigators to find out if mail fraud was involved.

Transmission: This was an era before 4//5 and 6 speed transmissions were available and synchronizing low gear in three speeds was unknown. He found that double clutching to get into first gear while moving looses time; however, he demonstrated to me how well he could double clutch. His solution was to modify the Ford transmission to add synchromesh to first gear of his special. This was no small challenge. When synchromesh added to first gear that gear now spins at several times the top gear speed, all the time, creating many problems. While Chuck thought this was a break thru compared to the chassis and offered to sell plans for this modification few were interested.

Odds and ends: Engine camshafts of that era were crude and many local machinists thought they could build a better" winding stick" as they were called. Chuck created his own lobe profile based on a sign wave and had it machined at Iskenderian for his special. The Manning special was built in a detached two car garage behind Chuck's home in Inglewood, CA. As you reported no cars were built for sale. The last time I saw the car it had an egg crate grill and the headlamps were facing to the rear (typical Manning thinking-- headlamps are required but they might have less drag facing to the rear).

Ron Dona


Joel said...

I have copies of the blue prints but, I want to learn more about the Manning Special. Is there any way that I can get Ron Dona's email address?

Ron Burton said...

I have been looking for a set of blue prints for the Manning Special. Will sell me a set, and if so, how much? Thanks Sincerely, Ron Burton. I can be reached at burton.ron@yakimaschools.or