# Franklin Sport 4 engine

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#### Mflyer

##### Active Member
Supporting Member
I find it hard to believe the Franklin Sport 4 engine is not being produced as a kit of engine parts to be assembled for home built airplane builders or a shop the way it was 50 years ago. No FAA TC is needed. The Franklin Sport 4 could be upgraded to solid state ignition, automotive spark plugs, Bing carb and other external changes similar to the Jabiru 3300 engine selling at an affordable $20,000. The Sport 4 has 235 c.i. (125 hp) but weighs the same as the Continental O-200 about 210 lbs. The small Continental and Lycomings are 1940s production technology. From the responses I've got, some are negative about the Jabiru 3300 engine quality. Yes they had more than their share of problems initially but the Generation 4 version solved them. Kitplanes magazine describes the details. Last edited: #### challenger_II ##### Well-Known Member So, buy the rights, and the production equipment, and bring it back to the market. #### Groundhog Gravy ##### Well-Known Member Supporting Member #### BJC ##### Well-Known Member Supporting Member The small Continental and Lycomings are 1940s technology. What technology do you think the Franklins have? BTW, about 20 years ago, the Franklin importer had an engine in a C150, and was working on an STC. It was higher HP, but also was considerably heavier. It is difficult to compare weights of engines unless they are actually weighed with the same accessories. BJC #### Hawk81A ##### Well-Known Member [QUOTE="Mflyer, post: 659943, member: 106115] 1940s technology. [/QUOTE] Hmmmm. Double overhead cams, 4 valves per cylinder? 1930s technology on the early Allisons. Dennis #### TFF ##### Well-Known Member What technology is the franklins? There is no profit for a small run engine. They can barely keep the doors open with what they do. They definitely can’t supply parts on any type of schedule. Has nothing to do with physical engines. When the Tucker auto company bought Franklin for the factory to make their engines in, Tucker did not care about it he airplane engines. It’s been picking up pieces ever sense. If you got 2000 people who like the design, 20 of them have the cash. You can’t make money selling 20 engines unless it’s a one man show. #### Pops ##### Well-Known Member Supporting Member What technology do you think the Franklins have? BTW, about 20 years ago, the Franklin importer had an engine in a C150, and was working on an STC. It was higher HP, but also was considerably heavier. It is difficult to compare weights of engines unless they are actually weighed with the same accessories. BJC My daughter and her husband at one time had a 1948 Cessna 170 that had been converted to a 6 cyl Franklin in 1950. Changed it back to the Cont- 0-300 and lost 80 lbs on the new EW. Made a huge difference in the handling . #### Tom DM ##### Well-Known Member Supporting Member What technology is the franklins? There is no profit for a small run engine. There is profit in literally everything and with the right price a market will develop. It is not a coincidence that after WOII suddenly small aircraft/ manufacturers boomed. If the price / ownership / usage becomes stupidly expensive, the market will collapse. A secondary effect is that such allows the Chinese to pick the bits up which they will sell it back *with a profit* further down the line. I've got as many , some very first hand, examples as you might like. Nor Franklins, the Lycomings nor the Continentals (nor the "oldtimers" as Piper/ Cessna etc) have not the slightest reason (inflation corrected) to be more expensive than at their introductuction, in fact these products should have beaten inflation by considerable margin. As well as from deduction as personal dealings with some I know why this is. #### challenger_II ##### Well-Known Member I think I just wet myself, laughing... #### Vigilant1 ##### Well-Known Member Supporting Member Nor Franklins, the Lycomings nor the Continentals (nor the "oldtimers" as Piper/ Cessna etc) have not the slightest reason (inflation corrected) to be more expensive than at their introductuction, I wonder if these same engines really are considerably more expensive today, after adjusting for inflation. Anybody have a source for historic engine prices? We know that in 1958, a Cessna 150 sold for about$9,000. For a total WAG, let's just say the engine was 1/3 of that price, or $3k. Adjusted for inflation, in 2009 that would equate to$22,270. According to this 2009 Kitplanes article, a new O-200 with all required accessories could be bought for $21,499 that year. So, about the same. Inflation adjusted to today, that$3000 in 1958 would be $29,844. That might not be today's exact price, but I doubt it's off by more than 10-20%. It doesn't seem that these engines incredibly more expensive today than they were a half century ago. Last edited: #### Wanttaja ##### Well-Known Member There is profit in literally everything and with the right price a market will develop. It is not a coincidence that after WOII suddenly small aircraft/ manufacturers boomed. And went bust, almost immediately. The US trained a lot of pilots during WWII, and the assumption was these men were going to want their own aircraft when they got home. Manufacturers surged...and lost their shirts when the anticipated boom didn't happen. It's not a coincidence that a number of aircraft companies either merged or went bankrupt in the ten years after the war ended. This plot uses the FAA registration database from 2005, and plots the number of aircraft on the registry by their year of manufacture. The boom/bust is pretty obvious: The problem is, there is *already* a good replacement engine for the small Continental-powered aircraft... the Rotax 912. Ron Wanttaja #### Tom DM ##### Well-Known Member Supporting Member Asking data before Internet is not that easy, yet ... 1952 O-290D = 1.258, 38 US$
1 USD (1952) = 10,85 US$today => Engine cost corrected for inflation to 2022 = 13.764 US$

Now, Vigliant1 : your turn... what is the price on a new O-200 2022? Because I have been asking, I have been banging on doors, and I have yet to receive an answer.

#### Tom DM

##### Well-Known Member
Supporting Member
And went bust, almost immediately. The US trained a lot of pilots during WWII, and the assumption was these men were going to want their own aircraft when they got home. Manufacturers surged...and lost their shirts when the anticipated boom didn't happen. It's not a coincidence that a number of aircraft companies either merged or went bankrupt in the ten years after the war ended.

Hi Ron,

I knew you knew

However: I also know that close to none of the engines used by the aspiring producers were new (as in new from the factory). Military surplus ruled.

On Baladin (F-PJKV) the c-90 14F was new 9/11/1965. I need to search but somewhere I have its original invoice at 650.000 Anc Francs (France). I stuck in memory as -I presume- Maurice Paumier wrote a note to it : "Voleur".

BJC

#### Vigilant1

##### Well-Known Member
Supporting Member
Simple adjustment for inflation isn't all that needs to be considered. For our standard of living to improve that means that that the whole of last years consumption (and savings) needs to cost less this year. If an item (engine in this case) still costs the same, with simple adjustment for inflation, that means it actually is more expensive compared to the populations disposable income .............. presuming the population actually has a higher standard of living. Not so sure that is the case last year for many of us?
As individuals, it would be possible for our standard of living to improve even if goods/services escalated at the same pace as overall income. Many/most people experience this as their skills increase over their working lives and their pay increass.
Overall, you are right. But things do get cheaper because technology improves and competition forces better goods and services to be produced at ever lower prices.
Certified airplane engines would be expected to be an exception. Few manufacturers and very high barriers to entry reduce competition. Certification/TSO requirements seriously impede product improvements. That's why it would be surprising to me if they did remain close to the same inflation-adjusted price.

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#### Pops

##### Well-Known Member
Supporting Member
About 1971, a factory new Lycoming IO-360, with mags, Bendix FI, and starter ring gear, cost about \$4,200.

BJC
I started building a house in 1970. Built full basement and the 3 bedroom house shell under roof for about the same amount of money. Built the house myself as I had the cash, so I know how much it cost.