912 HC Power curve

[MetBlue]

I'm looking for power curves ( torque and HP) for the late 2.2 HC engine ( Spec 10 ) but can't find anything.
The only thing I found looked so linear and perfect it couldn't be correct and said something about an approximation ( automobile-catalog.com)

I have a curve from my engine taken about 8 years ago on a Dyno, so not BHP, but curious how it might compare for reasons I'll go into another time.


Tony

[John]

Hi Tony, the Lotus sales brochures have a graph showing torque and BHP on the tech spec page. I've got a 1986 and 1987 brochure showing the graph for the 912 Excel SE 912 engine, they look the same. Rather than post a picture here's the figures, RPM, torque in lbf.ft., power in BHP;

2,000 130 50
3,000 140 80
4,000 150 120
5,000 160 140
6,000 150 180
7,000 140 175

All figures there or there about, the graph is printed quite small! The torque plot is flatter and falls away more significantly after peaking at 5,000 compared to the BHP which plots a steep straight line from 2,000 to 5,000.

Cheers

John

[Tanz]

This was mine back in 2007 - probably lost a few horses since then!

[bash]

I never used to rev mine over 6000 because it didnt seem to improve after that. Ive not seen these graphs before but they do seem to confirm my thoughts.

Bash

[Essex Metallic]

This is interesting, thanks for posting.

I tend to to rev above 6000 anyway but it looks like I'm not missing out on much on my standard HC engine.

How high do the Lotus Bits engines rev to out of curiosity?

[fueltheburn]

LB 2.2 is higher revving than the 2.5. maxes out around 8k.

The race spec 2.5 runs out of puff around 7-7.5k. The torquier more tractable roadgoing version is out of puff at 6.5k depending on cam selection and other items. Things tend to really kick off around 4k. The 2.5 on mine how I set it up was not linear in nature.

[Pete Boole]

Lotusbits new 2.5 crank design might let it rev higher now - the original had a terrible out-of-balance vibration phase at about 7200 rpm.

Pete