torquey 250 xflow setup - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

XE302 · 10-25-2004, 00:17

G'day

I was wondering what kind of (relatively inexpensive) mods would improve the low down torque and overall fuel economy of an alloy head 250 crossflow, things like cam profile, balancing, exhaust, carby? I've got an XD wagon with a standard engine (with it's emission spec cam profile & webber) running a close ratio 4 spd and 3.23 gears, and I have another engine to play with, as well as a standard ratio g/box and 2.92 lsd. I'd love to have the same kind of low down torquey feel as my standard 3 spd 221 XT, which pulls from much lower revs and uses significantly less fuel too with the same final drive ratio. I'd like it to rev freely too.

My guess would be that a similar profile cam to an XA 250 with a decent exhaust would increase power, torque and economy. Would the webber be best, or a Holley? I suspect the webber.

SiX_iN_a_RoW · 10-25-2004, 01:44

I would rebuild the weber. The 250's have weird rod and crank setup so they have nice torque but arent all that happy to rev. There are a couple of rod and piston combos you can play with which will help it rev. Id suggest taking a look at www.fordsix.com eg. 200ci rods will give a slower piston speed but allow the engine to rev up to nearly 7000rpm from memory

A shorter diff ratio will help heaps ( even better would be a 5 speed behind it ) but you will run out of puff on a stock engine. If you use a cam profile that will allow it to make nice power a bit higher in the rev range than a stock engine you will be laughing, also the obvious mods, bit of a port job, set of extractors etc it should perform nicely

Oh and for a small mod, rip the aircleaner assembly off a carby XF, they take the air from the inner guard

needturbo6 · 10-25-2004, 01:44

my opinion- extractors, exhaust and a rebuilt/tuned 350 holley and a cam to suit these mods. depends how much u wanna spend really and at what price u can pick these up.

i think either way it would be much easier to tune the holley and the torque/fuel economy would also be noticably better.
balancing it would also be a good idea as it will rev a lot easier and i dont think they were balanced enough (or at all) from the factory.

ive heard the efi-model head is a good upgrade but i know the late 87 efi xf heads are better and they all(?) have the right valve seats for unleaded-type fuels, i dunno if yours runs on "leaded" or not....

also megatork camshafts are one of the cheapest too, and are made by crow. if your gonna get a cam i would think a newly devoloped profile would be heaps better too.

deankdx · 10-25-2004, 02:14

[QUOTE=XE302]G'day

I was wondering what kind of (relatively inexpensive) mods would improve the low down torque and overall fuel economy of an alloy head 250 crossflow, things like cam profile, balancing, exhaust, carby? I've got an XD wagon with a standard engine (with it's emission spec cam profile & webber)

basically sounds like an XE motor
i am fitting an EFI cam to get a bit more(not much) mid range
in your case if you want more bottom end grunt you would need to advance ignition timing as much as possible(without pinging) and perhaps advance cam timing(you'll need an aftermarket timing chain and gear set with multiple keyway) extractors make a considerable difference to midrange power say around2500 to 4500 ish probably shaving the head for a bit more comp would also benefit bottom end torque, i would keep the 2 barrel webber as you will not have to worry about emissions issues with any cops
these motors like tall diff gears so i would keep 2.92 unless your planning to tow a very heavy trailer or something

INJECTED250 · 10-25-2004, 04:40

215@0.050 cam or smaller and no more than 480 lift, keep the webber there a good carb, i would change to 3.23 diff gears, and manual... extractors a good the longer the primarys the better.
Shave the head but not to much as u will end up with to much pree load on lifters and will need to shim the rockers...
expect around 200 hp fly wheel using a 215 @ 0.050 cam good webber , stock manifold and stock exhaust maniflold, with decent compression.... and good clean alloy head, use e1 e2 sereies head, with nice open chamber, if using c2 head remove chamber that sits between valves, and clean up exhaust port c2a is like c2 but has a layed of chamber, it looks like it should work good..

needturbo6 · 10-27-2004, 06:04

the reason i prefer the 350 holley is prob coz of a couple of experiences.
had a cortina with no mods except the 350 holley and xf head had pretty good torque and fuel economy was also pretty good if i drove it sensibly.

webber would still do the job on the cheap and i suppose with the money from putting a holley on you could spend it on something more worthwhile.

INJECTED250 · 10-27-2004, 06:08

or what about a dodgey small turbo set up .. monsta torque