power difference



My brother just leant me a magazine titled A complete History of falcons.

it contains a few facts that i dispute, however here is one i cant make sense of: they claim the XA was powered by a 127Kw 250. yet the XD is powered by 94 kw 250 slug why the difference, is it all the pollution control regulations, i wouild howvere have thought that the alloy crosflow head, along with electronic ignition would be capapble of a higher output.

cheers smythee
Revised cam, cam timing, little carb, EGR valve, honesty in reporting figures... They all stack up to make the difference. At least you're building on a better platform.
Ha Ha Ha. Ford Power figures are sorta like the bloke who saw Elvis walk out of the 711...no-one doubts what he saw but was it really Elvis?

All power outputs before 1979 in Austraila were often gross ( so called SAE Gross) readings with the donk tested on a dyno with no accessories (no fan, not the full exhast, not the power steering pump {if available}, no heavy duty heat correction rah rah rah).

After 1979, all Australian market cars had readings which were the German DIN standard, a reading with all the accesories on, and with a stricter heat and barametric correction. That 1972 170 horse 2V 250 WASN'T REALLY 127 Kw rated by the DIN readings... it was more likely to be around 16 percent lower, around 109kW or even less. The old 2 litre Cortina motor was rated at 112 horses SAE, but only 98 horses DIN.

Another thing is that the stricter emission standards (ADR 27 in 1973, and the dreaded ADR 27A rules for mid 1976) took a big bite out of peak power. The Holden 202 used to be rated 135 hp (101 kw) in pre-emmisions trim in 1972, but had only 76 kw DIN in 1979. In truth, it had probaly lost 16 % from the rating change, and another 15 % from the ADR 27A regs which required an air-pump /EGR system to clean the old hump up!

By comparison, the Alloy Head Falcon XD 4.1 only had 94 kW, but this was DIN net rating, and was 2kw more than the XC 4.1. The 2V XA 250 may have produced about 94 KW as an emissions motor. The reality is, that whith the power ratings and emissions changes, it was nothing to loose a charted 30% off a 1972 6 or V8 figure.

There are a few other things to consider too. Ford, like the others of the big Three, were often ecomomical with the truth. Mick Webb is on record for saying the best blue printed Phase III engine he had tested produced 260Kw in a dyno cell. The gross rating from a Car Craft magazine in 1982 stated the 4V HO 351 was 380 hp (284 kW) SAE gross at 5800 rpm. Yet Ford Oz said it had 300 hp landed in Aussie.

Then the XE 4.1 carb started with 105Kw in 1982 but was derated to 98kw in 1983. It was the same engine, no changes! And an XE 4.9 never had 140 kw if it was 2 seconds slower over the standing 1/4 mile than a 149 kw 5.8 XE (police spec would have done sub 15.8 sec quarters, like the heavier XD S-Pac) The 4.9 was also heaps slower stock than a 126kw 5 Litre SL/E VB Commodore which weighed only a smidgen less. Oh, and Ford said the 111 kW XE EFI 4.1 did 16.9 sec 1/4 miles while the 140 kw 4.9 4-spd took 17.3 sec. Even the 98 kw XE carb 4-spd did 17.6 sec quarters. And the 4.9 LTD Modern Motor tested in 1983 couldn't get under 18.8 for the quarter! That so-called 140 kW motor must have been more like 128 kW or less.

And just ask this. If a 2-barrel 240 HP 302 had 179 KW(SAE) then in a 1389 kg XA 4-spd Hardtop, it should have done better than a 16.9 sec quarter. An EFI XE does that with 111 kW AND 1435 kg to haul around! I'll bet a STOCK 1972 Cleveland 2V 302 has less DIN kW than a stock XE EFI 4.1!
bloody hell, if only theyd all pick a standard to work from.

i reckon maybe the qtr mile time differences could be to do with teh gearing in different cars?

i have a idea most of the V8 auto ltds were a 2.53 diff, therefore making em slower
From the info I've been given, only the non air conditioned XE 4.1 Falcons had 2.56:1 diffs.

All V8's from 1966 on were likely to run 2.77s or 2.92:1 as a Borg Warner, or 2.75 or 3.00:1 if a 9 " diff is used. Despite what you read on the Ford Web site about the later pre XR 6 sixes being over geared, diff ratio's don't make a heap of difference over the standing quarter.

Phase III Falcons might have done 14.7 sec quarters with 3.25:1 diff ratio, or 13.9 sec's with a 3.9:1 diff and close ratio box when drag raced one up.

Diff ratios help a little, but it's pretty hard to figure out how an XF EFI 4spd with a higher 2.77:1 diff and 1470 kg and 121KW could do 16.4 second quarter (Wheels 1984), while a so-called 140kw XE 4.9 4-spd with 1450 kg, and 2.92:1 did 17.3 according to the Ford add on the first XE EFI six published in many Oz mags in 1983.
Maybe its because V8s are crap!

lol. IIRC it was the XD / XE economy pack Falcons that came with the 2 pinion 2.53:1 diff.

heh. I've heard that the Holden 27A motors required air pumps and other things that made them run rough in order to pass emissions, whereas all Ford needed was to go crossflow.. a mild engineering feat indeed :)
That's right, it was 2.53:1! My mate is trying to track one of those down for his 5 speed EFI 4.1 powered TE Cortina. It's got a wide ratio Toyota Hi Lux gearbox and can only fit 23.5 inch tyres on the back end. He wants to have about 27.2 mph in 4 th at 1000rpm, and 31.6 mph in 5 th with his 225/60 13 tyres. He's crazy, but with a modified six, he never needs to use first even if towing his trailered beach buggey up a ramp! At the moment he runs a 2.92:1 BW 7 7/8 diff.

The thing is, if Oz Ford V8'S like Cleveland 302/351's had properly matched cams, carbs and ports in the first place, (along with valves that didn't drop when the revs got over 5000 grand) they would have gained a much bigger following. Having 90 to 120 thou thin wall cylinders that split under regular service and NASCAR blocks that weighed the same as a 400 Ford kinda makes it a stocky pudding compared to Windsors.

The cross flow 4.1 has so much torque it usally holeshots ANY V8 in the first 50 yards on the street. Even the smaller XR6 4.0 motor in the 1529 kg (3371 lb) EB Falcons produced quarter mile times bang on the calculated maximum because the gearing was bang on. In magazines, these things fronted up with 3800 lb plus on the strip, and only 220 hp, but did 15.2 sec standing quarters when 15.1 sec would have been the optimised time by the formulas I've seen. All this with a long stroke, short rod block that is far off the ideal interms of peak power.
Did you guys know that, aside from the fibs on power out put that Ford has been involved with over the years, there are a few more:-

Eg 1, Fords 5.0 V8 is really a 4.9 with 4942 cc capacity. The Aussie XC/XD/XE Falcons had the last Cleveland 302's (a destroked 351 C 2V) and called them 4.9's, so that's true. The EFI 5.0 Mustang/Falcon engine was the same 4.9 liter donk...they just called it a Five Point Oh cause Chevy, Holden and Chrysler had one bigger!

Eg 2, A 351C/W/K/M isn't a 351, it's a 351.8. And like you care....

Eg 3, A Holden 202 never was a 202, it's always been a 201 cid engine. GM-Holdens just told lies and every one else belived it. The 3310 cc engine became a 3298cc engine in 1976, but it was the same engine all along!

Eg 4, Holdens HQ/HJ/HX/HZ sedan fuel tanks varied from 75 to 63 litres during the 7 year model run, but it was the same tank all along!

Eg 5 Fords XD/XE/XF had a variable wheel base if you read Fords Falcon handbook. But it was the same wheelbase all along!

Eg 6 Ford claimed the XE had a reduced turning circle with it's introduction in 1982, but there was no change over the last XD.