XC Bathurst Cobra - 170MPH???

[4vxc]

Originally Posted by Kieron

If I remember correctly, the 5.8's put out a whopping 162kw's, exactly the same donk as the P6 LTD. These engines also had vac secondary spreadbore Carter Thermoquads and I thought they were rated around the 800cfm mark? They were certainly massive jugs, I seriously doubt whacking a Holley 750 on would increase top speed by much at all. Rev limited to 4,800 + calculating the diff ratio would give us the theoretical top speed.

dont forget they were rated SAE net, not gross like earlier models
there wasn't as much difference as you might believe, like someone else said we used to block the EGR valves with a plate, advance the timing, change the air cleaner or if were broke flip the lid and they were just as quick as XBGT's

[290GTP]

Finally found it. Original road test of the Bathurst Cobra had the top speed at 204 kph. Interestingly the 5.8 GXL 4 speed topped out at 197 kph. Maybe the hardtop was slightly more aerodynamic. Same motor, same gearing.

[XR Martin]

Originally Posted by Sprint

I had a XE 351 toploader with 2.77 gears, the way it was geared I worked out mathematically it was capable of 300kmh @6000rpm.

All you need is the HP to get there, flacon don't handle the best at 300 though lol.

More like about 260kmh, unless it was running massive wheels.

[XB GS 351 Coupe]

Originally Posted by XR6 Martin

More like about 260kmh, unless it was running massive wheels.

Probably had tractor tyres on the back

[pottery beige]

Originally Posted by FairmontGS

Agree, I still buy it because I have every edition but I have stopped "reading" it. Usually just flick through then file it.

bump for this

[4vxc]

Originally Posted by 290GTP

Finally found it. Original road test of the Bathurst Cobra had the top speed at 204 kph. Interestingly the 5.8 GXL 4 speed topped out at 197 kph. Maybe the hardtop was slightly more aerodynamic. Same motor, same gearing.

sounds about right those figures could be pretty variable too, run on public roads maybe slightly up or downhill, different weather conditions ect

[290GTP]

Originally Posted by 4vxc

sounds about right those figures could be pretty variable too, run on public roads maybe slightly up or downhill, different weather conditions ect

Yeah, very true mate. They said the front end felt like "it was rooted in granite" with the extra strut bracing and with the 16:1 steering box the wheel was pretty heavy at parking speeds.

Apparently it was a marginal classic. Lols.

[XB GS 351 Coupe]

Originally Posted by superpursuit05

Part of the reason I stopped buying AMCM. Too much myth being printed as fact.

Originally Posted by FairmontGS

Agree, I still buy it because I have every edition but I have stopped "reading" it. Usually just flick through then file it.

Haha, I have not bought a single car mag since 2007, and only bought that as my car was on the cover

Imagine all the money I have saved and the room I now have spare to store useful crap.

[XR6WGN]

Originally Posted by Stefan

How recent was the sale?

Asking price for Auto 302 cobra is 100K these days.

$120K for a Bathurst model I'd say 170MPH was the speed of potential buyers to this dudes front door.

While the XC Cobra is underpowered compared to a GT, they have become a valuable car..

Sorry Stefan, just saw your question. I originally placed a copy of the for sale article from Unique Cars on 14Jan16. I am unsure of the actual sale date but I received my magazine this week. So I guess the sale was in the last month or so. He said in the article that he had three offers of $125,000 - after he had worked out who he wanted to sell it to, he didn't mention the actual price - I'm guessing it would have been around the offered price!!

[XB GS 351 Coupe]

Wanted to buy a 351 manual Cobra back in the late 80's, but thought the $10K asking price was outrageous, should have just bought it back then

Really Cobra's and John Goss Coupes were not seen as anything special back then and were considered under powered compared to the GT's

[seven7]

Originally Posted by Ford17

Just thinking, if Moffat's racing XC 'Cobra' was hitting a maximum speed of 159 MPH at the end of Conrod straight, how much more would it have had, if the straight was much longer?

not sure how true it is but if u listen to the video it says 159 mile an hour at the speed camera half way down conrod

so who can shed some light on where it was????

[amiers]

and that was actually a XB GT, just had XC cobra panels and upgrades.

[XB GS 351 Coupe]

100% correct, most people don't realise that the 'XC' race cars were actually the old XB race cars with XC panels pop riveted in place, yes pop riveted, not even done properly

[4vxc]

Moffat has a a several times they used to pull 160 mph

[nuthin' fancy]

Originally Posted by 290GTP

"it was rooted in granite"

Wouldn't that hurt your back?

Late '70s road cars were pretty amenic compared with cars even 5 years earlier and especially cars of today.

[superyob]

Originally Posted by nuthin' fancy

Wouldn't that hurt your back?

Late '70s road cars were pretty amenic compared with cars even 5 years earlier and especially cars of today.

What does this word mean?

[ozpacman]

I worked at Ford dealer when the XC's were new and none of them, including the 5.8's could pull the skin off a rice pudding in standard form.

Maybe that 170 mph XC Cobra owner never realised his speedo was actually calibrated in metric . . .

. . . should have gone to spec savers!

[castellan]

Originally Posted by Sprint

How many revs does your legs do?

Its hard to tell if a motor is stock or not from the outside, 6000 is not a lot of revs in top gear, a stock 2.0 escort will do 200kmh, there was a thread the other day about a Daewoo lanos getting 190. My xr8 sprint would do 200 in 4th gear with another gear to go.

I'm not saying its possible with a stock motor but would be easy with a worked motor, apart from the flying brick scenario. Aero and the HP needed to push it through the air is its worst enemy.

It's got nothing to do with legs, it's the theory.

A mate had worked 202 G Pack Torana that could do 7000 RPM now it had a 3.36 ratio diff and 14inch wheels, now some clown could say in theory it could do X KM/H boy ! what would it do with a 2.78 or 2.6 ratio ? fact is it will not because their are other factors that come into play in reality.

My stock 6sp manual SS could pull 260KM/H in 5th but in 6th it was flat out doing 210KM/H now it would rev to 6250RPM limited, but some clown could say by working out 6th gear x 6250 you get = 430? KM/H

[mik]

Originally Posted by stevefreestyle

Did you play around with the dizzi timing on the dyno with XC 351 ? Way back in the '70s when I had a XB & XC 302, I found the best way to kill the performance was to use a timing light to OEM (pollution) specifications. Unfortunately the "pollution" wasn't the only thing it killed - as reflected in the drop in official power figures of both 302 & 351.

With my bum on seat & ear dyno, I found a huge benefit in increased power, rev range, and responsiveness by throwing the timing light away, and removing every second plug lead off the dizzy cap, idling it up to about 2500 - 3000 rpm, and carefully rotating the dizzy back & forward to find the sweet spot - which was considerably more advanced than OEM.

Removing every second plug lead puts load on the engine, and helps magnify the sweet spot. Naturally you replace the plug leads when finished (lol)

A lot of the motors in the era had trouble with dieseling when you switched the motor off, commonly they got a couple of degrees of timing knocked out of them and the idle speed loweredlowered in an effort to stop it, sometimes cars would come in for a service and you'd switch them off and they run on terribly, and sometimes with a big cough and then a very violent run backwards for a second , then stop.
On another note I can remember my old boss taking an interceptor/candy car for a high speed run up the highway to test a modification on the auto, her reported the top speed was 192 kph, obviously every car is different and has a slightly different time , but there you go, stock police car with 351 and 3 speed auto, still an awesome limo though.

[Pedro]

Just a side note:
An experienced racer friend of mine was one of the 15 invited by Audi to drive one of the 15 new R 8's they flew to Australia for a drive experience on Bathurst on Monday after the 12 hour.
As pointed out by Garth Tander, the road R 8's are quicker that the racing ones as the 12 hour rules makes them bolt on restrictors.
It got to just over 300 kph before he backed off ( P Zero road tyres) for the Chase.

[mik]

Originally Posted by castellan

It's got nothing to do with legs, it's the theory.

A mate had worked 202 G Pack Torana that could do 7000 RPM now it had a 3.36 ratio diff and 14inch wheels, now some clown could say in theory it could do X KM/H boy ! what would it do with a 2.78 or 2.6 ratio ? fact is it will not because their are other factors that come into play in reality.

My stock 6sp manual SS could pull 260KM/H in 5th but in 6th it was flat out doing 210KM/H now it would rev to 6250RPM limited, but some clown could say by working out 6th gear x 6250 you get = 430? KM/H

I remember the old G pak, they where a bit average in the handling department,
rode pretty good with the the Dunlop aqua jets, I don't think I'd want to do more than 120 kph in one though, my step father had one,
fit and finish was utterly despicable, brand new came with blown up diff, door trims that vinyl covering did not have enough material to cover the cardboard in the trims, and somehow they left k of the GPak sticker, even the paint was different shades around the car.
A bit of a low point in Holden's history.

[XB GS 351 Coupe]

Originally Posted by ozpacman

I worked at Ford dealer when the XC's were new and none of them, including the 5.8's could pull the skin off a rice pudding in standard form.

Maybe that 170 mph XC Cobra owner never realised his speedo was actually calibrated in metric . . .

. . . should have gone to spec savers!

Haha thats probably it, a misprint and it was supposed say 170km/hr NOT 170mph....now it all makes sense

I mean how would he even know his car went 275km/hr (170mph) when the speedo only goes to 220km/hr

[Blue Roo]

I think the Seller was trying to make has Cobra more special and faster, than the Phase 3, 4 or even Phase 5. LOL!!!

[MethodX]

On another side note..
Ford built 13 pre Cobra Cobras, with all the Bathurst Cobra specs.
A one off order batch for Ford teams
Called the GS homologation pack.

Chassis numbers commencing with JG65TE.

[ljf12]

Does anyone know how they measured top speed figures back then. I vaguely remember a "fifth wheel " they used to attach to the side of the car but can't recall what era that was.

Unlike modern vehicles I am pretty sure a lot of speedos back then were a little optimistic in regards to top speed.

[XB GS 351 Coupe]

Originally Posted by ljf12

Does anyone know how they measured top speed figures back then.

Get on the Hume and hold it flat to the boards as long as you dare

[mik]

Originally Posted by ljf12

Does anyone know how they measured top speed figures back then. I vaguely remember a "fifth wheel " they used to attach to the side of the car but can't recall what era that was.

Unlike modern vehicles I am pretty sure a lot of speedos back then were a little optimistic in regards to top speed.

not much has changed i think in regard to the optimistic speedos, , if memory serves , the XYGT was only 4 mph out at 145 mph , a true 140 mph ... quite good , but plenty of other models not so accurate,
but accuracy then much like today varied with different models .

[ljf12]

So how did they check the speedometers accuracy back then ?

[PHATAL]

I know of a fairlane 351 with the 2.77 that used to pull just under 6000 RPM in top gear regularly. Granted it had a few motor mods. Most people will probably call bs on that though.

[SSVPom]

Interesting comparison between XB and forthcoming XC power outputs, apples for apples