Lotus Elan

Lotus Twincam Engine Modifications

PostPost by: Matt Elan » Tue May 23, 2023 7:13 pm

Thanks for doing this Rohan - thats my bedtime reading sorted!
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PostPost by: rgh0 » Tue Jul 04, 2023 8:28 am

Back from my holiday in Europe and managed to finish Chapter 8 - Building a good breathing cylinder head. See the attached PDF file below



Now I need to finish chapter 9 about all the ancillaries that need to be considered to ensure your modified engine is reliable while finshing my current engine build and before I do some Skiing in Australia and head back to Europe for some more summer...... I am enjoying my retirement :)

cheers
Rohan
Last edited by rgh0 on Tue Jul 04, 2023 8:37 am, edited 1 time in total.
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PostPost by: Andy8421 » Tue Jul 04, 2023 8:34 am

Rohan,

Thanks again for all this. Required reading for anyone thinking of rebuilding a twinc.

Andy.
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PostPost by: skelteanema » Thu Jul 06, 2023 10:16 pm

Thanks Rohan, a great resource. Have enjoyed reading each chapter.
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PostPost by: h20hamelan » Sat Jul 08, 2023 5:16 am

good clip on valve float

https://www.youtube.com/watch?v=_REQ1PUM0rY&t=20s

though I wonder if it keeps the valve seats clean :) no carbon buildup eh
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PostPost by: nmauduit » Sat Jul 08, 2023 8:19 am

thank you so much Rohan for sharing and taking the time to put your experience down in a widely useable form !

a great help to keep the spirit alive...
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PostPost by: rgh0 » Tue Dec 26, 2023 10:16 pm

[email protected] wrote:Does anyone in this Forum got any informations about IWR camprofiles ?

I have a nice pair IWR 155 cams - 11,1mm lift - 7/16" camlift

Best regards , Roger


I have never seen details but given the lift and age of the cam it will probably be a long duration of about 310 to 320 degrees seat to seat and only usuable in a full race engine

cheers
Rohan
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PostPost by: LCRJ » Wed Dec 27, 2023 2:25 pm

Hi Roger,

Yes, I'm interested in IWR and doing research on it.
IWR had four type of cams for Lotus TC.
155 is stage3 race cams.
.433 lift 58/89/89/58
So duration will be 327
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PostPost by: rgh0 » Wed Dec 27, 2023 10:11 pm

Hi Hiro
where did you find the details on the IWR engines. I would be interested to understand more about the details of their modifications back in the 60's and 70's

cheers
Rohan
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PostPost by: LCRJ » Sat Dec 30, 2023 3:05 am

Hi Rohan,

I sent PM.

Kind wishes,
Hiro :D
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