XM Falcon crank into grey?

[weedy-burton]

EXERPT form last months street machine.

" A new car for this year, an FJ Holden, ran 107 Mph with the old sideplate Grey motor. Any one who can run one of these engines, which have 5 main bearings from memory, and a bit of bent fencing wire for a crankshaft to this speed, deserves to feel very proud. I have been told that one of the tricks with these motors, is to use the crankshaft from an XM Falcon. It adds much strength, and can rev safely well over what a standard Grey motor could cope with"

anyone heard of this mod being done before,and what mods need to be done to the crank to get it to fit?

Cheers

Weedy

[4hammers]

Well, That's new .
NEVER heard that before (but will stand corrected). I know that the Vauxhall steel crank for a PA PB model will fit if squeezed hard enough. There is a mate of mine down here (TAS), that runs a JWF Italia (1960's kit car) & he has a Grey motor with a Vauxhall steel crank. He went through 3 motor blocks to get one that coud be used. The bores need to be re-aligned. The bearings need to be re-aligned & YOU need to have about $3,000 to $4,000 to get you motor running sweet.  
Best bet, is a set of main bearing strengtheners or the very rare full strengthening caps. Then it will rev to 8 thou.
Goodluck,
RJ

[weedy-burton]

Found some pics of it;

[FE_225]

They use to fit Falcon cranks into reds, but never heard of one in a grey.
As Rob said, Vauxhall cranks were the go years back.
There is a guy in Sydney supposedly fitting Buick cranks to greys, Ed Ho can give you his details if your keen.
As mentioned, main cap bridges and a preped stock crank will pull 8000 rpm no probs, 107 mph with a grey ?? tooo easy!
Cheers
Tony

[4hammers]

True, Tony.
I got the wagon up to 95 MPH with the stock Grey . Scary, but easy. Man, with a Norman bunged on, what do you reckon?? 125 - 130mph?? Woooo Hooooo
Rob J

[Paul Kelly]

95 real MPH or did you believe the speedo

Lindsay Wilson from QLD set the record on the salt in 93 at 109 real MPH. and it still stands.
Not as easy as you think
He also drives a Norman equiped EK Wagon as an every day car,

Getting a grey motor to perform and return accurate almost three diget speeds is achievable, once the magical 100 is reached climbing in single didget numbers upwards becomes much harder.

[FE_225]

Yeah! 95 in a stock bodied FE is scary. My old bus use to pull  more than 70 mph in second at full howl and would accelerate like buggery when you floored it at 90 in top. When the motor was fitted to the EJ stock car is was clocked on radar at 128 mph around the track.
Blown and pulling big revs, 130 shouldn't be a problem, if you've got the balls to push it  that hard!!!

Hey Paul
I know Lindsay, and don't doubt his claims. Pushing an FJ to 109 is a real feat and full credit to him for doing it. If other guys went to the trouble of having their grey powered beasts offically timed across the salt, I'm sure the results would be very interesting

Tony

[Paul kelly]

So why has this record stood for 10 years, with 120 to 130 MPH grey motors out there.

[4hammers]

Well, I suppose if you got real technical, the speedo could be out  at 95mph, but it is spot on at 40mph, 55 mph & 70mph. So, I thought it would be about right. 95 mph was scary, & that is about all she would do, but it was frigging howling along the Midlands Hwy in central TAS. Loong, straight & cool. FUN!

I am not sure what salt flats we are talking about & know Lindsay quite well (He is one of the "Norman" brother hoood ). I like his EK & rteckon that is where a Norman belongs.

I cannot quote any figures off a mates car down here, but will get some details soon. The JWF Italia of his (like I stated in the first post) is a bloody monster. He has spent upwards of $25,000 on that motor. He has run every possible combonation (even a Repco Hi power crossflow) & has charted the results for it all. It is very competitive & has completed 2 Targa's. I have no doubt at all it would reach 130 mph. I will visit & get the details.
Rob J

[Paul Kelly]

Dont think I doubting your claim, but I have owned and built some tough greys in the 70's and thought they were capable of of 100 plus easily.
Had an oportunity to run a couple on a dyno and the speedo readings varied to the dyno figures over 80 and  105 was the best achievement. The speedo was telling me something totally different.
A three diget reading can be achieved with a normally asperated Grey, a blown version should return better numbers .
The record of 109 is for a carburated grey.
Running on the salt is far different to at the drags or some industrial estate late at night, the speed has to be maintained at peak revs for a longer period for timing on the runs on flat ground.

Only time will tell when someone will set a new record.

[Jockster]

Interesting set of discussions happening here, until broken officially I would think the official record has to stand, however my very first car was a 48 series with a very worked grey motor, which had main bearing braces, very worked head, triple carbs etc. Flat out the speedo neddle would bounce from 90 mph to the stop and back, but by my calculation, from engine revs and gearing it would do 123 mph. My calculations were incorrect however as it went through a Police Amphometer flat out one night and was clocked accurately at 110 mph. Luckily I managed to outrun the Police car and get home and in those days if you made it home they couldn't book you, but I did get a tongue lashing and a stern warning that they would be keeping an eye on me from then. Unfortunately a week later the car succumbed to my limited driving skills of the time and a large gum tree, which gave me some time in hospital to reflect upon my behaviour. It was a fast car however and at that same time there was an FJ running around here with the Phil Irving Head on it and it was a much faster car than mine, I would imagine it was capable of a genuine 120 mph.
Cheers
Jock

[gp]

Hi Guys,
A mate of mine runs a 48/215 in the Group N (Appendix J) that regularly pulls 135mph down the straight at Eastern Creek. Apart from some careful machining & assembly (with a few tricks up his sleeve), it's basically just a grey motor running triple SU's and extractors. It's also fairly reliable. He's had only 1 crank breakage in about 9 years of racing. It regularly sees 7500rpm!

Cheers,

Graham.

[EJ_Dave]

If you were trying to set a grey-powered speed record why would you start with anything but an EJ shell? Surely aerodynamic drag would be substantially less than earlier models. Tony's post suggests this is the case.

Sounds like a challenge to me. And I reckon a wagon body (like...say, mine) might be even more aerodynamic than a sedan. Anyone have a hot grey they would like to loan for a crack at the record? I think it would be pretty cool to do it in a stock looking slightly dog-eared wagon. I could even leave the kiddy seats in for effect.

Whadya reckon?

David

[RET]

I know the kiddie seats have got the full 5 point harness, but even so,  make sure you don't leave the kiddies in them. Weight reduction and all that...

Seriously though, wouldn't the weight of an EJ shell cancel out the drag coefficient gain?

cheers
RET

[EJ_Dave]

I'm a bit reluctant to disagree with a guru and all but I would have thought that aerodynamics would be more important at the top end than weight. Greater mass would slow acceleration, particularly at lower speeds, but not have such an effect on top speed on a flat surface.

What would the weight difference be anyway? I think EJs are lighter than FB/EKs but heavier than 48/FJ. Not sure how they would compare with FE/FC.

Off the top of my head an EJ wagon weighs about 1200kg and a sedan around 50kg less. Pretty light really, so I wonder how much lighter a 48/FJ would be.

As a scientist, I feel an experiment coming on. How about someone with a hot FJ does a top speed run then we transplant the engine into my EJ and do it again- same place, same day. We might have to repeat it the next day (in reverse order) to account for any time of day/temperature effects. Then we could get to the bottom of the weight (we would have to weigh them both) vs aerodynamics argument.

Sounds like a fun weekend!

David

[4hammers]

Mate.
Too true, very fun indeed. I would love to bring my Copcar over & go for a howl (When it is finished.) It will have a Norman, but I am not after any records, just a bit of fun. I know Lindsay & he has mentioned these salt flats before. I reckon it would be a great idea to get a few of these cars together for a run near the time of the FE FC Nationals in Jindabyne 2005. I don't think it is too far away. Tony will have hiss Norman Blown FE ready as well. Man, I can just see it now.
YEEEEEEEEEEEEEEHAAAAAAAAAAAAAAAR!!!!!!!!!!!!!


Good idea???
Rob J

[mcl1959]

The advantage the FX and FJ have over the later greys is 15 inch wheels, they wont get off the line quicker than a later grey but they certainly pull away at the top end because of the bigger diameter tyres.
I would think an FJ would beat an EJ every time with the same engine assuming cars were both sound.
But an EJ would beat an FE,FC,FB or EK because of aerodynamic shape.
This is why you rarely saw later models such as FC to EJ at Bathurst.  A few ran FE's but struggled to be competitive and gave them away
Ken

[EJ_Dave]

I presume Ken the larger tyres just give taller effective gearing which I hadn't thought about in the context of this discussion. However, I have fitted a taller diff ratio to my EJ which would go some way towards compensating. With the same effective gearing things might be interesting.

We'll have to make sure the EJ and the FJ have the same effective gearing in our experiment. Maybe do some diff and rim swaps while we're at it. Maybe we need a team for this and another team for the engine swaps.

The relationship between gearing, aerodynamic drag and the revs at which the engine produces maximum power is interesting. Maximum speed is achieved when resistance due to aerodynamic drag, driveline friction and rolling resistance (tyres squishing and unsquishing) is equal to power put to the ground. To achieve maximum speed potential for a given maximum power output, driveline and body size/shape, gearing needs to be such that the engine is revving at the point it produces maiximum power at the same speed where resistance is equal to this power.

For example if it takes 90rwkw to push an FJ to 100mph and the engine produces this power at 5000rpm then the gearing needs to allow the engine to be spinning at 5000rpm at 100mph (20mph/1000rpm). If the gearing is lower or higher than this, (giving say 4500rpm or 5500rpm) the FJ won't make the magic ton. The optimum gearing for an EJ would probably be higher than for the FJ due to less aerodynamic drag. This is opposite to the actual gearing differences between the two.

None of this really clinches the argument but I reckon that with the right gearing and the same engine output an EJ would have a higher top speed than an FJ (or any other grey-powered Holden) because of its lower aerodynamic drag.

Of course cars got a lot more powerful between 1948 and 1962 so the EJ would have been much less competitive in racing against its contemporaries (Mk11 Jags, Mini Coopers, Big V8 yank tanks) than the FJ was.

I reckon the idea of a get together at a salt flat/drag strip etc around the time of the next Nationals would be interesting (are EJ's eligible?).

Seeing Tony's Norman charged beast at full tilt (as well as swags of other old Holdens) would be awesome.

Cheers,

David

[RET]

Don't worry about disagreeing with me, I have no experience on this topic whatsoever.  My comment about EJ weight was mildly tongue-in-cheek...

RET

[4hammers]

Hi All.
I have got some info off the record holder himself. After what he has explained to me, I 100% agree that it is a bloody hard feat to beat & it is no wonder the record still stands.
Here is some of the rules for the comp.

The timing markers are situated over 3 MILES with a 3 mile run-up and a 3 mile slow down strip following (Total of 9 MILES for the full track). Does anyone realize how long you must keep it at full noise when you have 3 miles to cover to average out your speed? I give full credit to anyone who even makes the pilgrimage as a spectator, let alone to race! You May now be able to see why 109+MPH ! I applaud the guys who ran 107 this year!

Point taken.
3 miles at full noise in a Grey is not as easy as you think. How long is the straight at that race course that these cars get to 135mph? Not 3 miles I bet. It is quite easy to get a car to touch 100mph, but to hold it there, that is when things start to wobble loose. Not advisable if you want a complete motor at the end of that run.

Long & the short of it is, if you haven't got the record in your hands, then whatever you say is just speculation. You reckon you can beat it, give it a go & then see what we see.
Regards,
Rob J