Lotus Elan

Twin Cam Red Line

PostPost by: Matt Elan » Tue Nov 27, 2018 4:14 pm

Looking at the Europa (Sorry) it seems that the late Special with the Sprint spec Twin cam has a red line of 6750 rpm, but all the literature that I've got on the Elan, Plus 2 and Europa says 6,500. The Special did get a 'new' tachometer (A074 N 6004Z) which replaced 054 N 6001 which was carried through from the Series 2 to the twin Cam. I've seen pictures of standard Special with the read line at 6750.
So my question is did Lotus change the red line on the Twin cam for the Europa Special with out upping it for the Elan Sprint or the Plus 2 130....
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PostPost by: benymazz » Mon Dec 03, 2018 4:22 am

Late to the party on this, but my guess is that it had to do with the early rods being the weak link. I think that the top end could handle higher rpms, but the bottom end was (comparatively) weaker. When the Elan started production the now-infamous L-type rods were used, and this continued up at least through 1966 I believe. These seem to be well known for creating unwanted crankcase ventilation holes when run over the red line, and this is somewhat well documented: I have a brochure from Lotus East from around 1968 that lists step one on a list of things to do when converting a road TC to a racing TC as switching over to the 125E rods. The 125E rods were stronger and would have been standard equipment by the time the TC Europas were being produced.
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PostPost by: rgh0 » Mon Dec 03, 2018 6:53 am

I believe Lotus changed to a 6750 rev limiter from 6500 rpm at some time after the introduction of the sprint specification engine.

Dont think they ever changed the tacho to match in the Elan or Plus 2 but it looks like they did in the late Europas.

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PostPost by: Chrispy » Tue Dec 04, 2018 4:36 am

In Miles Wilkins book he notes that the rev cut on the distributor was 6750rpm for the big valve engines, and 6500rpm for the rest.
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