Top Speed

[NES304]

What is the top speed of a stock grey FC? I only drive mine around local streets and finally went up the highway. It barely got to a hundred (Klms/hour - Speedo read 62mph) before it started running out of puff.
Everything is stock.

[zulu]

Either your speedo is out or mine is Nes 138, my green special will do 75 mph or better on a good stretch of road although it does have larger than standard pistons.

Maybe your engine is still a bit tight, have you done many miles on it yet?

One way to check your speed is with a Sat Nav, not sure if these are accurate though

Gary

[Geoff_K]

You had better believe Gary about doing 75mph (120 kph).
I followed him on to the express way from GreyPride a couple of years ago, for a cruise back to Sydney and thought he would be easy to keep up with: hell no.
As he said his green special is not quite standard, but I certainly goes.
My blue special has 186, hr discs, 5 speed, 3.36 diff, 14in wheels and will sit on 120-130 in the fast lane without any trouble.
Very quick trip back to Sydney, Gary spent most of the time in the fast lane, so I can vouch for his speed. (I was a bit worried however about his ability to stop in an emergency)
As a teenager, with cross plys, many years ago my FE217 (and my blue special) would run to about 80 mph on the speedo, which conservatively would be 125 kph.
Easy to check these days, the gps will give exact reading.
Next chance I get I will try to get a reading on Gary.
Cheers, Geoff 

[ratbox]

my first registered car was an EK flat out by the speedo 82 mph and recently an EK ute good for around 70 - 80mph as has been said not sure of acuracy, also as has been said GPS local highway cop reckons there good to within about 3kmh

[NES304]

The answer is yes, it has been checked by a gps. I took my navman to check as I new the speedo is old or out. A gps should be acurate. A B767 can use it to place itself on a runway in crap weather!
I'm thinking it might be a problem with the carby as it is coughing but can't help thinking that the gearbox and difff ratios act like a speed govenor. maybe they should do that for P platers

[CraigA]

What diff ratio and tyres does it use?

If its got the stock 3.89 and you are using 60/65 or even 70 series radials I reckon that you've pretty much hit top speed as the stock grey isn't going to rev much past 4500 rpm. If you post your tyre size and diff ratio I can calculate a theoretical top speed.

Have you tried the test with the all windows up, cowl vent closed and leaning forward? You might get a few extra mile an hour 

[NES304]

185 75 r13s..... stock diff, whatever that is?

[CraigA]

Stock diff is 3.89:1

Calculations as follows:

4500 RPM =   82.34 MPH   
4000 RPM =   73.19 MPH
3500 RPM =   64.04 MPH

So from this its easy to see that your car isn't reaching its maximum potential. Have you confirmed that your carby linkages are allowing full throttle?

If so and it is OK then you need to look at engine timing, especially the condition primary and secondary ignition circuits (check points and plugs/leads, coil output), check the air filter assembly to make sure its not restricting flow, and if nothing else is the culprit then check valve timing.

Is the engine reasonably fresh? Maybe its got a carbon build up preventing engine breathing? What about the heat flap in the exhaust manifold - not stuck closed or partially closed is it?

In top gear you would think that a good stock grey engine could pull 4000 RPM, so is therefore capable of just over 70 MPH. This matches with the description Geoff gave of Gary (Zulu's) car.

[FC427]

Might be a good idea to change in to 3rd and then 4th gear to get the old girl going over 80 MPH  Forgot it's a grey  ...Sorry for the poor sense of humour>>>> GREY IS GOOD<<<<<<<.......FC427......

[Trevor_B]

Hi Nes,
Should be able to get at least 80 on a good stock grey motor. During a run around a certain well known proving ground there were plenty of standard greys making this and better speeds...

The example below was running 185/75 radials and a 3.55 diff. (speedo since verified as fairly accurate with a GPS) and was apparently on 3/4 throttle so may well have squeezed out a bit more speed.





The Green & White Wagon on the high side was reputed to be doing over 100 although it has a warm grey...

Regards,
Trevor_B

[CraigA]

Should be able to get at least 80 on a good stock grey motor.

It ultimately depends upon gearing. In your configuration the 3.55 raises your potential top speed for a given engine revolution.

Diff is 3.55:1

Calculations as follows:

4500 RPM =   90.2 MPH   
4000 RPM =   80.2 MPH
3500 RPM =   70.17 MPH

So in your picture you are doing 4000rpm. If you can get more than an extra 500rpm from a stock grey then it ain't stock.

Calculations have been made using this tool.

http://www.kabamus.com/garage/gears.html

[gp]

Have never checked my speedo with a GPS, but speedo was reading a touch over 90 at Lang Lang. It wounds out to an indicated 80 quite easily & then builds up to 90 a bit slower. When travelling to & from Melbourne last year for Holden's 60th we sat on 70-75 for most of the trip.

Diff is stock, I think tyres are 175/80 x13, Stock engine overbored to 138ci, with slightly larger valves.

When travelling back from Melbourne a few years ago, we sat on 80-85 for about 45 minutes...........the temp light started to glow faintly......... backed of to 70 & the light went off again.

I would suspect there is certainly something wrong if you can't get much more than 60 out of it? I think Craig may have the answer, check your accelerator linkages to see if they're adjusted correctly, it sounds like you're not getting full throttle.

Cheers,

Graham

[Johns]

I've now had six grey motor Holdens and bless 'em they were all different.

Unless you know the history of the engine, what's inside makes a big difference as to how they perform. My lovely yellow EJ had a tired engine and never felt comfortable at speed despite having a 3.55 diff fitted.

My blue FC wagon with a reconditioned EJ motor felt very strong. Nev, my FE, has a reconditioned original motor 40 thou over, balanced with a slightly warmer cam - I think - feels very comfortable at a 60 mph cruise as did my blue FE. Both had/have standard diffs. Thelma, my grey FC wagon also felt strong at 55mph, should be a lot better when the engine's right I suspect and we're testing this with Thelmas's 2nd new motor, that balancing is the key to smooth grey. I will keep you posted.

In my experience, a good standard grey with the stock 3.89 diff and correct tyres will run at 55 - 60 mph very comfortably. Over this, to me, they don't feel good - they feel strained. Compare this with my 149 EH, its a different league, smooth quiet and competent.

As much as I advocate stock because I love the charm of original cars, the red motor is such a quatum leap over the grey if I have another engine blow up, I would search for a little 149 as Craig has put in his FC. They're only 2.5 ltrs and a lovely motor, no matter how hard you drive them with their seven bearing crank and short stroke they never sound or feel strained.

Cheers - a fairly conflicted

John

[REDMR2RED]

My original FC Holden back in 1964 (a mere lad of 18) used to sit on 85mph to Ballarat and back on many an occasion.

I also had her up to 100mph down Wheelers Hill (VIC) once just to be able to say I had driven at 100mph.  Well that's what the speedo read, although possibly not accurate wound round that far.  Why I never killed myself or blew the engine up with the things we did back then I'll never know.

Red
P.S. I think the statute of limitations have expired for exceeding the speed limit, but maybe there was a de-restriction sign (remember them?) on that road back then.

[NES304]

Cheers for all the replies fellas. Looks like I might have to talk the misses into another rebuild....Looks like 60mph is my max then.

What is the stock diff ratio?

[RET]

Stock diff is 3.89:1

Later diff centres have the ratio stamped on them, but 3.89:1 diffs don't.

3.55:1 goes well with an otherwise stock set-up. Personally I think 3.36:1 is getting a bit tall, but I know people who've had them. Mind you, I know people with 3.08:1 centres mates to grey motors and crashboxes, but I reckon that's got to be very hard on the clutch and first gear...

cheers
RET

[weddo]

Interesting reading,

Mine has stock diff, 215/65/13 tyres, worked motor and has run 167K/h (104mph) on the dyno.
I had it up to 90mph on the way to Mnt Gambier (and checked with the GPS) but wouldnt push it the other 14 mph just to see if I could match the dyno results

regards
Weddo

[NES304]

Interesting reading,
Mine has stock diff, 215/65/13 tyres, worked motor and has run 167K/h (104mph) on the dyno.

Just Bragging now heh heh, stil, I am jealous. And she just confirmed there is no chance of dollars for rebuild. Unless she gets a new car but then there wont be enough for the motor.
Any know how much 3.55 gears are (cheers for advice ret)?

[CraigA]

3.55 centres can be found under $50.00 if you try old style wreckers.
They pop up on ePay now and then as well.

You need a coarse spline type - later models had fine spline axles.

[CraigA]

If you want one call this guy

Classic Oz Wreck
2/ 18 Sara Street , Toronto, NSW 2283
Phone: (02) 4959 4546

Greg is a good fella and will ship stuff anywhere.