HCI or not?

[judgea]

a) I have an 87 turbo, plate says manufactured in Feb., 87, serial # SCCFC2OA3HHF61006. In all the literature I read, I can not tell specifically when the HCI (high compression) series was produced in the G cars in & around 87. Can anyone tell me, does the serial # hold the answer? Who can I contact to determine if mine is HCI? Owner's manual was a replacement manual, so I can't rely on it.

b) Literature pre-HCI G cars says max. speed = 152 mph. Anyone know max. speed on HCI G-car?

Thanks.

[Esprit2]

Your Federal 1987 is an HCi.

The USA never got the High Compression carburetted engine HC). The Bosch injected, High Compression engines (HCi) were introduced to the US market with the 1986 model year and carried through 1988.

152 mph? That might be a little optimistic for a Federal HCi. Where did you get that figure? A British magazine? Specs for DOM and FED cars were different. I think you may find 146 mph and 0-60 in 5.1 seconds more realistic.

Regards,
Tim Engel
Lotus Owners Oftha North
Minnesota, USA

[judgea]

Thanks for the info. Got the 152 figure on an old Esprit advertisement I bought from LEW. Also in a book I have, "Lotus Esprit, The Complete Story". Questioned in a few places, but apparently confirmed in other places in the book. Unless my speedo is generous, I've done 150 twice, with pedal room remaining & my Lotus still gaining speed.

[Esprit2]

All Lotus speedometers are generous... "They all do that, sir". Typically by around 5 mph.

Regards,
Tim

[judgea]

Well, 5 mph isn't too bad. I'm intend to have a state policeman friend "clock" me. I'll post results if/when I get it done.

[Esprit2]

You can use a stop watch and the mile markers along the freeway to check your speedo's accuracy.

Later,
Tim

[bojangles]

my speedo, electronic, S4s, is really optimistic... out by as much as 10 mph.. very frustrating..
any adjustment.? the odo seems out too.. i mean if i drive at 60 mph a mile clicks by in a minute . but my friends following me are saying jeeze you are slow...
Bruce

[lotusguy]

bojangles said:

my speedo, electronic, S4s, is really optimistic... out by as much as 10 mph.. very frustrating.. any adjustment.? the odo seems out too.. i mean if i drive at 60 mph a mile clicks by in a minute . but my friends following me are saying jeeze you are slow... Bruce

Bruce,

If you cover a mile in exactly one minute while your speedo registers 60mph, then you are right on and your friends are either mistaken, or their speedos are inaccurate since a mile a minute equates to 60mph.

That having been said, your speedo may still have errors. Any error(s) aren't necessarily linear, and you may be accurate at 60, but off at other speeds.

Try using a stopwatch and a measured mile (mile markers on an expressway for instance, or known measured distances between streets etc.)

At 30MPH, you would cover that same measured mile in 120.00 sec., 40MPH would take 90.0 sec., 50MPH - 72.00 sec., 70MPH - 51.42 sec., 80MPH - 45.00 sec., 90MPH - 40.00 sec., 100MPH - 36.00 sec., 110MPH - 32.72 sec., 120MPH - 30.00 sec. etc.(all times are rounded to nearest 0.01 sec.).

The math is fairly straightforward. Take any speed, divide by 60. Divide 60 by the resulting total to get total seconds that any given speed equates to.

Example: to find out how many seconds it would take to travel 1 mi. at 80mph - 80/60 = 1.33333, 60/1.33333 = 45.00 sec. (actual Time (in sec.) required to travel a measured mile at 80mph.)

To measure speedo inaccuracy, take actual recorded time (in sec.) for a measured mile, divide 5,280 (ft. per mi.)by actual recorded sec. yielding ft.per sec. Multiply ft.per sec. by 60 to get ft. per minute. Divide 5,280 by ft. per minute to get miles per minute. Multiply miles per minute by 60 to get the distance (in mi.) travelled in 1 hr. or MPH. Then subtract the speedo reading to get the MPH. error.

Example: 45.00 sec. recorded time over a measured mile:
5,280/45.00 = 117.33333(ft.per sec.),
117.33333 X 60 = 7,039.9998(ft. per min.),
7,039.9998/5,280 = 1.3333332(mi. per min.),
1.3333332 X 60 = 79.999992(MPH.)
If speedo reading was 82MPH, then 82.0 - 79.999992 = 2.000008MPH your speedo is off.

A simpler way to do the math would be to Multiply the ft.per sec. by 3,600 or 60² (X 60 =ft.per min. X 60 = ft.per hr.) and then divide by 5,280(ft.per mi.).

Example:45.00 sec. recorded time over a measured mile:
5,280/45.00 = 117.33333 (ft.per sec.)
117.33333 X 3,600 = 422,399.98(ft.per Hr.),
422,399.98/5,280 = 79.999996 (MPH)

Note: Due to the fact that most stopwatches measure only to 0.0001sec., the results can only be close approximates to the actual speed as in the example above. Hope this helps. Happy Motoring! ...Jim'85TE

>> Edited by lotusguy on Sunday 15th August 14:50

[bojangles]

I meant a mile on the odometer, If there were any decent mile markers id do as you say. but they seem to be missing allover the the highways here.

And keep in mind that I write in miles for the Americans, Here in Canada mile markers are all in km ( when you can find them ) , my car is in mph so i have to calculate a bit in my head.

I am very sure that my system ( odo and speedo) are very optimistic.

[lotusguy]

bojangles said:

I meant a mile on the odometer, If there were any decent mile markers id do as you say. but they seem to be missing allover the the highways here. And keep in mind that I write in miles for the Americans, Here in Canada mile markers are all in km ( when you can find them ) , my car is in mph so i have to calculate a bit in my head. I am very sure that my system ( odo and speedo) are very optimistic.

Bruce,

As I'm sure you're aware, it's easy to substitute meters and kilometers in the formula to get speed.

If it's your odo which is in question, this is most affected by the tire diameter. Of course, now you are measuring strictly distance, no time component involved at all, so I'm confused how that can relate to your friends saying you're slow ???

I know that the tires on my car revolve 841 times per mile. If the gearing on the odo matches this, it's accurate (mine does not as the tires are not stock size). You can get the revolutions per mile for your tires from the manufacturer's specs on that particular tire. A speedo shop can adjust the odo to match this spec. Of course, this doesn't take into account any wheel-spinning.
Happy Motoring! ...Jim'85TE