9 replies to this topic

[hatrat]

I am trying to determine what head configuration was used in period (up to 1963) on the Cosworth Ford MkIV Formula Junior engines primarily used in the Lotus 27 FJ.

Was the period Cosworth head a modified standard head or was it a totally new modified casting? Is the current Richardson head used on a number of current FJ cars a copy of a period head or is it a subsequent non-period casting?

[Patrick Fletcher]

In the Haynes - Ford Tuning Manual [April 1964] page 100 states that the Cosworth Ford Mark IV FJ specification is identical to the Mark III. ie cylinder head is of cast iron modified to Cosworth specifications.
The Mark XI 1100cc Formula Junior Cosworth engine gets steel crank and rods but not much is said about the cylinder head for that series.
Is it correct that the engine for FJ had to derive from a homologated touring car.

[Ray Bell]

The head casting had to be from an homologated car...

The block also. Modifications, naturally enough, were allowed. Somewhere or other I have the FJr regulations, but they're not easy to find as things stand. Maybe they're on the net?

[Dick Willis]

I am trying to determine what head configuration was used in period (up to 1963) on the Cosworth Ford MkIV Formula Junior engines primarily used in the Lotus 27 FJ.

Was the period Cosworth head a modified standard head or was it a totally new modified casting? Is the current Richardson head used on a number of current FJ cars a copy of a period head or is it a subsequent non-period casting?

I reckon it is as you have stated at the end of the last para.

[hatrat]

Thanks for the responses to my query. I have now had a look at the period FJ regulations which state:

a. The cylinder block, including the cylinder head and cylinders (if the latter are removable) must be those of the engine belonging to a car classed by the F.I.A. in the touring capacity.

So I presume this means that the recast Richardson head (which is a copy of an F3 casting?) cannot be a period FJ head.

[Patrick Fletcher]

The A-Z of Formula Racing Cars 1945-1990 on page 273 has a note about the FJ regulations.

[Ray Bell]

Originally posted by hatrat
Thanks for the responses to my query. I have now had a look at the period FJ regulations which state:

a. The cylinder block, including the cylinder head and cylinders (if the latter are removable) must be those of the engine belonging to a car classed by the F.I.A. in the touring capacity.

So I presume this means that the recast Richardson head (which is a copy of an F3 casting?) cannot be a period FJ head.

I would say not...

Even if it was to all appearances identical to the original Ford casting, it's possible it has 'improvements' that might make it possible to flow more gas or withstand more revs or hold the rocker shaft more rigidly or something.

But that doesn't mean it will be outlawed. People running in Historic classes can often put over great claims that enable them to 'cheat' legally. Here we have the Group N racers (particularly the tintop boys with '65 and later V8s) being allowed to use NASCAR style blocks on the basis that 'every block made in the sixties has now been overbored 0.040" and they've been worn out again. They were only ever good for one rebore, so they're useless for racing!'

So why not let them have a block that gives them a lot of meat for boring out, cross-bolted main bearings, greater rigidity etc? Makes sense, doesn't it? Even the $6000 price tag is just plain common sense.

[Patrick Fletcher]

Do think we are talking about heads rather than blocks - most people would take OE as what was available at the time. If you want to alter the original rules then you must know the proper methods to bring about that change.

[Ray Bell]

Certainly, but I was citing an example of how things are done...

It's easy to go from there to see how a car owner or a number of them can 'suggest' that an aftermarket head should be allowed because it's becoming impossible to source original ones.

[ianselva]

Do think we are talking about heads rather than blocks - most people would take OE as what was available at the time. If you want to alter the original rules then you must know the proper methods to bring about that change.

Although it is a few years since I raced in Formula Junior, I remember there is a rule specifically relating to Richardson heads. I think it states that they can only be raced in the late rear engined class, which would make it OK for a Lotus 27.
It would be best to check with Duncan Rabagliatti or Grant Wilson as they may have tightened up the regs since then.