Adjusting rev limiter

[Heuer]

Thanks Richard

I know what speed to operates - 5,500 rpm consistently - It is adjusting it I was interested in. Paul Matty have sent me an original Lucas standard one which is what they recommend along with being alert and circumspect whilst driving!

[ricarbo]

I typed up a reply, after logging in, but when i submitted it it got lost and i was returned to the log in page, Does this happen to others or am i doing something wrong?
The gist of my reply is not to rely on an uncalibrated tacho. they are at least 35 years old. they are adjustable. easiest check is against a Satnav and the gearing spec, probably 17 - 18 mph per 1000 rpm, depending on specific model.
More details if of any interest, subject to replies not being kicked out by the system!
regards
Richard

[Heuer]

Richard

Again thanks for taking the time to respond. I am about to run some metrics on the car using a Road-Dyno and associated software which will give me both RPM and BHP/Torque figures throughout the range. Superb bit of kit for ?75. Details here: http://www.dynoplus.co.uk/roaddyno.shtml and this is the output from a run in the E-Type:



I also have a digital rev counter which I intend to use to cross check the readings on the original tachometer. I know from experience of the E-Type tach and generator they can under-read significantly so I don't want to blindly replace the limiter without being sure. The rev limiting rotor arm was a NOS Lucas item which has only done 4,700 miles (albeit since 1995) hence my concerns.

[billwill]

Nice looking gadget.

<f/x> looks in piggy bank.

[Heuer]

Glad I checked - the digital rpm meter is showing the rev limiter cutting in at about 6,100rpm. So assuming a 10% error margin on the (cheap) meter it looks to be about right. I will however do some more analysis with the Road-Dyno.

[ricarbo]

What a great piece of kit! Intriguing to know how it works. How can it know what the drag of the vehicle is? If you ran a test into a strong headwind, or with a strong following wind, would you get the same answer?
Richard

[Heuer]

Richard

The included software allows you to take into account gear ratios, diff, tyre size, humidity, temperature, frontal area, drag coefficient and altitude amongst other things. If it is windy (and good practice anyway) you do several dyno runs in different directions. The in-car monitor can store them all until you are ready to process them: