Lotus Twin Cam on a 116E Block

**Nickhale** · 26-12-2010, 20:41

Help!
I have a bit of a dilemma at the moment. Lotus twin cam head, standard but in very good condition. I have a 711M block, from a crossflow and a 1500 116E pre-crossflow cortina block. Both are complete with pistons, rods, crank etc. But i don't know which to use... 711M is stronger, but taller and requires some machining down and a spacer plate. the 116E block was the original lotus block (please advise if i am mistaken!) so it would be easier to use that, but is it strong enough? any help would be great, thanks,

Nick

**wildo105e** · 26-12-2010, 21:52

i have a lotus TC built on a 711 block and no extra machining is needed. You need lotus TC pistons in it and the spacer plate with a longer timing chain and that is it. You wil get a slightly torquey engine with the 711m block. The advantage really is you can take the capacity out further and get the benefit then.

**racing escort** · 27-12-2010, 11:09

Has the 116E the 4 or 6 bolt crank ? If it's 4 bolts take the 711M
The 116 conrods are not so strong, if you keep this block, change them for the 125E conrods and good bolts.
A 711M can be skimmed 8mm if you want to keep the short stroke, it can be bored bigger than the 116E ...

Like Wildo says, not much to change !

**Nickhale** · 27-12-2010, 13:19

It has the 6 bolt crank, so all i would need to change would be the pistons i assume to get the clearance from the valves? But to be honest I think i will try the 116E block, knowing that I have a spare when i end up with an extra ventilation hole in the side of it. I only have 40's to go on, so it won't be a powerful engine. I'll have a look around for 125E rods. how large can you take the crossflow lump out to? I would prefer the shorter stroke, I like the higher revs!, thanks guys,

Nick

**dangerousdave** · 27-12-2010, 17:06

The xflows like to rev too, most will go to around 1700cc (+90 thou). When you put the std size lotus pistons into a xflow it needs a +60thou bore for them to fit so its already around 100cc bigger capacity just from changing the block. Let me know if you need pistons, i have a couple of sets left that are NOS std size brand new from the last 3 crates from the lotus factory with rings and gudgeon pins.

**wildo105e** · 28-12-2010, 12:19

Originally Posted by dangerousdave

The xflows like to rev too, most will go to around 1700cc (+90 thou). When you put the std size lotus pistons into a xflow it needs a +60thou bore for them to fit so its already around 100cc bigger capacity just from changing the block. Let me know if you need pistons, i have a couple of sets left that are NOS std size brand new from the last 3 crates from the lotus factory with rings and gudgeon pins.

I can vouch for these as i got a set from Dave must be 5 years ago and spot on they are (still in the brown paper).

**Nickhale** · 28-12-2010, 14:53

PM already sent to dave... i think i will go with the crossflow as even if i used the 116E block, i would have to bore it out to accept lotus tc pistons. so i think the crossflow block is the way to go. foud some useful bits here http://www.lotuselan.net/publish/twink_rebuild.shtml

Nick

**charlespelayo** · 16-08-2019, 04:22

Originally Posted by wildo105e

i have a lotus TC built on a 711 block and no extra machining is needed. You need lotus TC pistons in it and the spacer plate with a longer timing chain and that is it. You wil get a slightly torquey engine with the 711m block. The advantage really is you can take the capacity out further and get the benefit then.

Do you still have info and pictures on your TC build from 711 block? I'm currently in a quest building an engine to install a Lotus valve cover on my cross flow 1300 with 711 block.