XC Bathurst Cobra - 170MPH??? - Page 2

Sprint · 12-02-2016, 09:46 AM

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.

superyob · 12-02-2016, 10:11 AM

Quote:

Originally Posted by FairmontGS

All a myth I'm afraid. I was closely acquainted with Cobra 029 some years back. It was stock as delivered with low kms and it barely made more than a standard XC 351 GT Power pack on the dyno. Looked great but a bit toothless.

????? Is this a misprint??? Do you mean GS?

superyob · 12-02-2016, 10:12 AM

Quote:

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.

Either do Falcons...

**FairmontGS** · 12-02-2016, 10:15 AM

Quote:

Originally Posted by superyob

????? Is this a misprint??? Do you mean GS?

No.
No.

superyob · 12-02-2016, 10:21 AM

Quote:

Originally Posted by FairmontGS

No.
No.

Ok, my mistake. Do you happen to have a picture of an 'XC 351 GT'?

Stefan · 12-02-2016, 10:24 AM

Quote:

Originally Posted by XR6WGN

According to the story - it was sold and is heading west (at a great rate of Knots

) he was asking around the 120,000 mark. It was in Unique Cars last month but the link is no longer available.

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..

**FairmontGS** · 12-02-2016, 10:27 AM

Quote:

Originally Posted by superyob

Ok, my mistake. Do you happen to have a picture of an 'XC 351 GT'?

No.

The official Ford name for the XC 4V motor was "GT Power Pack".

superyob · 12-02-2016, 10:29 AM

Quote:

Originally Posted by FairmontGS

No.

The official Ford name for the XC 4V motor was "GT Power Pack".

Thanks Fairmont GS. Learn something new every day...

wozman · 12-02-2016, 10:31 AM

I think there was just one real cobra that raced at Bathurst and it was painted white with red stripes

**Polyal** · 12-02-2016, 10:32 AM

Quote:

Originally Posted by superpursuit05

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

.

Yeap the current crop have rooted that magazine, it was good for the first 12 months.

stevefreestyle · 12-02-2016, 10:45 AM

Quote:

Originally Posted by FairmontGS

All a myth I'm afraid. I was closely acquainted with Cobra 029 some years back. It was stock as delivered with low kms and it barely made more than a standard XC 351 GT Power pack on the dyno. Looked great but a bit toothless.

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)

**FairmontGS** · 12-02-2016, 10:52 AM

No, it wasn't my car. Interesting what you say though. I used to tinker with my old 302 in much the same way until I felt that it was running just right. Never seemed to need a timing light.

**FairmontGS** · 12-02-2016, 10:55 AM

Quote:

Originally Posted by Polyal

Yeap the current crop have rooted that magazine, it was good for the first 12 months.

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

Ford17 · 12-02-2016, 11:15 AM

Quote:

Originally Posted by Ford17

Moffat - 159 MPH (255.88 Km/h) on his Hardies Heros lap in 1978:

https://youtu.be/jLk1EiK5R7s

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?

stevefreestyle · 12-02-2016, 11:17 AM

Quote:

Originally Posted by superpursuit05

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

Sadly, presenting unfounded & erroneous opinion as fact, is so often the case now, in this ignorant, narcissistic "Politically Correct", "Post Modernist" world - where objective truth is seen as irrelevant.

superyob · 12-02-2016, 11:25 AM

Quote:

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)

Probably a silly question, but do you mean you had 4 leads off at the same time or they were removed sequentially?

G6T · 12-02-2016, 11:25 AM

Quote:

Originally Posted by Polyal

Yeap the current crop have rooted that magazine, it was good for the first 12 months.

yep i stopped buying it for this reason as well. Its such a shame i enjoyed reading it.

stevefreestyle · 12-02-2016, 11:26 AM

Quote:

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?

Moffats XC Cobras started life here (as XBs):

Interesting article here:

http://www.bowdensown.com.au/collect...977-xc-hardtop

stevefreestyle · 12-02-2016, 11:31 AM

Quote:

Originally Posted by superyob

Probably a silly question, but do you mean you had 4 leads off at the same time or they were removed sequentially?

Yep running on 4 alternate cylinders, to balance the firing order and put load on the engine to make it easier to find the sweet spot. I also used to do it on my V6 capris with various hot cams - to great effect (8000 RPM).

G6T · 12-02-2016, 11:40 AM

Quote:

Originally Posted by FairmontGS

No, it wasn't my car. Interesting what you say though. I used to tinker with my old 302 in much the same way until I felt that it was running just right. Never seemed to need a timing light.

yep loved the 351 Cleveland nearly always tune it by ear, however my old xc pv early 90s mechanical solid cam 580-606 lift timing 36 total advance @ 3000rpm fill it up with avgas & away u go

stevefreestyle · 12-02-2016, 11:43 AM

Quote:

Originally Posted by G6T

yep loved the 351 Cleveland nearly always tune it by ear, however my old xc pv early 90s mechanical solid cam 580-606 lift timing 36 @ 3000rpm fill it up with avgas & away u go

Nice !

castellan · 12-02-2016, 12:01 PM

Quote:

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.

Mathematically the same is true of my push bike. gearing

A stock 5.8 XC Cobra will not pull over 210KM/H 215 at max with a Holley.

superyob · 12-02-2016, 12:25 PM

Quote:

Originally Posted by castellan

Mathematically the same is true of my push bike. gearing

A stock 5.8 XC Cobra will not pull over 210KM/H 215 at max with a Holley.

...

Stefan · 12-02-2016, 12:28 PM

Quote:

Originally Posted by FairmontGS

No.

The official Ford name for the XC 4V motor was "GT Power Pack".

Jeesus you just created an instant spike in the value of XC T code 351 cars.

Sprint · 12-02-2016, 07:13 PM

Quote:

Originally Posted by castellan

Mathematically the same is true of my push bike. gearing

A stock 5.8 XC Cobra will not pull over 210KM/H 215 at max with a Holley.

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.

MethodX · 12-02-2016, 08:08 PM

Quote:

Originally Posted by wozman

I think there was just one real cobra that raced at Bathurst and it was painted white with red stripes

And it wasn't a Bathurst model... just a normal cobra.

**Mesa** · 12-02-2016, 08:18 PM

Quote:

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 much more at all. The car was built and geared with the length of Comrod Straight in mind. No point in setting it up to go any faster than needed as it wouldve compromised the car in other parts of the track. Different story if it was set up for something like salt flats.

XB GS 351 Coupe · 12-02-2016, 08:33 PM

170MPH equals 274km/hr in a 351 Cobra

Thats hilarious, may be off the gap just before it hits the water at the bottom

351 XC has a theoretical top speed of around 200-220km/hr, does not mean it will get there in real life.

Kieron · 12-02-2016, 09:20 PM

Quote:

Originally Posted by FairmontGS

All a myth I'm afraid. I was closely acquainted with Cobra 029 some years back. It was stock as delivered with low kms and it barely made more than a standard XC 351 GT Power pack on the dyno. Looked great but a bit toothless.

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.

nt0351 · 12-02-2016, 09:32 PM

Quote:

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)

interested to know who showed you that method..I was taught the same way back in the day ,.....after doing it a couple of times though , I ended up taking the shortcut as they generally all ended up at about 12-14 deg BTDC.
as for the topic at hand ,clocking the speedo was about as good as it got .