250 X-Flow variances...FAQ needed?

[xctasy]

Without tryin' to 'post hog'...

The figures don't lie. Any auto 250 is a slow old hump, and it'll be hard to ever break 18 seconds for a quarter. It looses bulk power on a 4-speed manual, about half a second or more across the 400 meters. What is clear is that even though later cars are much lighter and more powerfull, they are not much quicker, but heaps more ecconomical.

A fuel saving of over 15% in nearly all cases.

x

 

[lyonsy]

hey there is also a 86da as i have one of them blocks and all the 250 xflow still have the allocation for the cortina dipstick but just not drilled,
the injection holes have been in since the 82da and are a good hp gain when welded up on a carby motor,
and i have also seen an 88da.
but intersting enough i have also sen 86da and 88da 3.2/3.9 engines to
mark

 

[P100 Ute]

lol

I have a 1977 Ford Cortina 4.1 AUTO (YUK) 250 Xflow with stock stromberg carby with extractors and a 2 1/4 inch zorst and my best is a 16.9 1/4 mile
not to mention it has stock 165x 13inch wheels on it
(i have it on video)

i have recently bought a XF EFI 250 Block whick im rebuilding to go in my Cortina and im putting a big CAM in it and full rebuild with a XF T5 Manual

and im hoping for 15's down the strip and later add a turbo (T04)

so dont say that under 18 sec aint possible coz i run 17.0 sec everytime @ drags.. and done a 16.9 once by luck

 

[xctasy]

Two up with over half a tank of gas, here's the figures.

(Incidently, the Cortina is 12% lighter than a Falcon, and headers give an 18% power increase at the rear wheels. Headers alone are like putting an EFI engine where the 123 hp 250 was).

My mates XE engined EFI 4.1 Cortina has extractors, 2.92:1 diff, and with Toyota five speed is as quick as a stock 351 XD. Which was 15.8 seconds in 4-speed from, 16.1 seconds as an XE ESP Ghia. Stock 1982 LTD's with the 4.9 and C10 (C4 derivative) couldn't break 18.8 second quarters, but a good 79 Fairlane could do 17.3 seconds.


Stock pre-emissions 250's with four speeds could do low 17's in Cortinas, no danger.

I've never seen a sub 18 second factory automatic 250 1-bbl or 2-bbl in a Falcon.


With manuals, I've seen 16.4 second XF EFI's , 16.9 sec XE EFI's, 17.6 sec XE 4.1 2-bbls, 17.9 sec 5-speed Falcon XE and XF 3.3's.

With autos, XC 500's did 18.6 seconds with 4.1's, XD'as did 18.5 secs, XD Alloy Heads did 18.2 seconds. XE Ghias did 18 secs. 17.8 sec 4.1 EFI Fairlane's. I've seen 17.4 second quarters in XF EFI wagaons with auto's. TE Cortinas with autos didn't break 18 second quarters with ease either. A badly tuned example ran an 18.3 in 1979 Wheels.


One day, I'll post them with chapter and verse. Incidently, Modern Motor showed the same Wheels vehicles were slower . Wheels never used electronic timing until 1985.

 

[Anonymous]

What is an 86da block?

Is it as good as, or better than the 87da?

I want the best/strongest possible block for my turbo 250 alloy head crossflow and I'd like to use an ef crank a bit later down the track too.

Does that mean I should only get an 87da block?

Where specifically are these codes (80da, 87da. etc) found on the block?

Thanks.

 

[xctasy]

Codes are true left of the car, beside the coil and towards the firewall on XC to XF's.

Best block is the last of the XF ute ones. They are new, cheap. I'm not sure that the main seal is very good, but at least its compatiable with the later crank. Some EL's were reported to use the AU crank, so don't buy until you've checked what you are doing with the 3 element crankshaft balancer and 12 counterweight crank.

 

[Anonymous]

Just to add a couple of thoughts on the iron X-flow heads, the on paper figures for XC iron head hide its true value.

A few years ago there were a few of us trying to decide what heads to use on our budget engines, we gathered some heads from each series & had them run over a basic flow bench.

I can't remember numbers now, but the end result was that the XC head kicked butt stock. Its not just the port diameter either, the XC heads were cast in a way that as the ports got further from the center of the engine (& carb) they were radiused back to wards the center of the engine.

Its major down fall though, is its weight, these thing are heeeeeavy, like nearly 2 people to lift it heavy (not really, but you know what I'm saying).

Ultimately we decided on alloy series II heads for a few reasons, alloy head less likely to detonate, much lighter, much easier to have modified & very easily repaired if an engine lets go, that way you don't loose all your port work with the head.


For a budget engine, fit larger valves & quick casting tidy up they would have to just about be best bang for buck street head.......but still very heavy

 

[xctasy]

Welcome. Love your site name, it rocks.

The old iron head is a weird old thing, with better pushrods, worse servicablity (no valve inserts, lifter removal without head removal is impossible except by your secrete PVC pipe method, very good!), bigger ports, odd sized heat bolts which are hard to find quicky, but must make Ford a lot of money.

The ports are odly biased, and round, very much like a 289/302 tunnel port head. I'm certain the guy who did the tooling-up must have done all his design at the pub, because looks so funny compared to the linear, symetric style of the Honds Ford heads.

Compared to the later heads, they responded better to a big cam than the small ports of the HF1to HF9 heads. About the time the Alloy Head came out, the X-flow would mop up any Holden to the tune of 1.3 seconds on a quarter mile. The Alloy head wasn't any quicker, its just that the XE 4.1's were 360 pounds lighter than a fat XC.

I like the iron head because they are heavy, have those lovely big ports, and all the later bits go into them. Except the intakes.

Ford sure knows how to give with one hand, and take with the other.

 

[Anonymous]

I agree, their a weird thing.

Although they are not symmetrical or linear, I've always wondered whether for single carb applications if the design of the iron head may actually be the least bias.

Never had the opportunity to put the theory to the test on a flow bench or anything. What I was thinking is, when you look at the head side on the alloys are more symetrical........but thats not the direction the intake mixture is coming from in a single carb application. If you look from the center outwards you can distinctly see how the shape of the port is actually helping turn the intake charge to the cylinders furtherest from the center through the final few degrees to arrive at the valve. The alloy heads (& XD cast heads) turn the intake charge for the end cylinder through a full 90deg in the manifold before going straight then into the port. The XC iron heads the mixture doesn't make anywhere as tight a turn or travel as far whilst in the manifold. It leaves the carb already traveling at about 30deg angle to straight ahead & then the final 60deg is a combination of the head & the manifold taking it around a fairly easy radius because it never has to get to that 90deg to manifold mounting face to make the entry into the head ports, which allows the intake runners to the furtherest cylinders to be shorter.

well that just a thought I had kicking around.

 

[Anonymous]

The oil pump drive shaft locator to the block is bigger on the 76DA vs the 80DA , and some Im told to belive have a retaining circlip on the pump drive shaft and most dont. I also noticed a different champher on the pump drive shafts ends but thats no biggy.

 

[Roath]

The x-flow blocks changed four times.
First was the 76DA,
then the 80DA,
then the 83DA
then the 84DA,
then the 87DA.

So does that mean the 87DA OHC has the same engine mounts and bellhouse mounting as the 84DA or did that all change? (i.e would a 87DA bolt straight in place of an 84DA?)

Cheers

 

[addo]

OHC has a different bellhousing but the 87DA and 84DA crossflows will interchange at the mounts and bell.

 

[Roath]

OHC has a different bellhousing but the 87DA and 84DA crossflows will interchange at the mounts and bell.

OK, so I guess my mistake is that I thought the 87DA was an OHC. What's the motor in the XG and XH Utes then and what did the 87DA come in?

 

[addo]

I'm pretty sure 87DA was the last design revision for the crossflow. It would have come out in late '86 and probably went into the highest-volume products (sedans) first. The XH ute had an OHC, not sure about the XG.

 

[myplague5]

Hey fellas,

I'll have a look at work on monday on some stripped down blocks, to check out the knock sensor mount on the 84DA style blocks. I've been working at http://www.engineexchange.com.au/, doing delivery driving and workshop hand jobs.. I know we've got about four 4.1 engines laid up in disassembly, theres bound to be an 84DA and an 87DA in amongst the mix. Theres also a selection of EA, EBII, ED, EF and EL motors around the shop if anyone wants particulars..

What is this.... looks interesting