mario wrote:unfortunately, without knowing what exactly the teams were up to at the time it is hard to know what exactly Brabham did do that lead to such reliability problems in 1984, and whether the use of "exotic" fuels did contribute to that.
Thanks for your detailed reply.
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Such a shame we won't know the details unless something like a former team member decides to shed further light on the matter. I guess as long as the public at large is not asking questions about Brabham. Then there is little reason for the true details behind circumstances like what we have discussed above, to be known. Perhaps us members of F1 rejects can start an internet movement, or something similar, calling for the truth to be brought into the public's attention. After all it would be against Bernie & his former team.
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For what it is worth, I've found another situation which might or might not be comparable to what we have discussed.
During the BBC commentary for the 1992 Portguese GP both James Hunt & Jonathan Palmer commented, in some detail on how Williams were especially concerned about their Renault RS4 engine reliability after changing the type of fuel they were using (IIRC from a specially brew mix to a standard pump fuel).
Patrick Head confirmed this to Jonathan Palmer & stated that the different fuel was causing increased vibration problems with their engine, hence their reliability concerns at that race. In fact Head stated he wasn't 100% sure they were going to make the finish as a result.
The exact explaination, which is too complicated for me unfortnately, of Williams problems can be found on this utube video of the race; at precisely 1.35.00
http://www.youtube.com/watch?v=Hnf1jHAnAlE
As I know very little of how engines work, I don't know how comparable this example may be with the Brabham case. Perhaps you (or someone else who is techincally gifted) will be better able to ascertain whether their are any parallels that can be drawn from these two cases?
Given the differences between the two types of fuels & engines in question. Not least the fact that the Renualt engine was normally aspirated whereas the BMW was turbo charged of course. I suspect there is little comparison of the specific details of both cases. But I thought it would be best to check with you in any case.
Nonetheless I think what Palmer said when he sums up his report on Renualt fuel reliability concerns is interesting. Which is..."it does go to show just what a delicate balance the engineering is". So it seems to me to be reasonable to think perhaps the use of "exotic" fuels would disrupt this 'delicate engineering balance'. Particularly with the ban on refueling during races in 1984, given what you have said above. Of course the question is to what extent?