EFI conversion on old 250 - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Pb.foot · 03-23-2004, 01:51

My mate and I are trying to get into the local drag scene around SA, and we want to show off some old school Ford muscle. It has come to my attention that due to the presence of a Holden plant and absence of Ford plant, this whole ****en state rides with the red army.

We have a 250ci X-Flow Inline 6 out of a cortina (don't ask me which model). We need to strip it down as it is old, so we wanted to make sure it was put together right. If any performance parts happen to land in the parts pile, we can't be held accountable

Does anyone have any suggestion how we can make this motor grunt?

I was considering ripping a MPFI system of an E-series and putting that on there. Is that possible (when I mean possible, I mean how hard/$$$). I don't have to worry much about computers and such, I'm redeveloping my own programmable system.

My main goal in all of this is to at least try and hold a candle to all my mates who drive VN's I know I'm working against a huge generation gap, but I can't afford a newer car, or to work up my V8.

Also, more generally, has anyone done one of these motors up b4? What kind of part am I looking at? Is there a lot of difference between building it up for carbie vs. doing it up for EFI?

Any help you can give me would help.

tiggers_ef · 03-23-2004, 02:54

try looking into a efi system that had the same bolt pattern to the webber, i know that there are still companies around that make adapters then it is endless to what you can do to it then.mind you im a rev head from the early eighties pre cross-flow 260+hp six, no car , motor in shed

xdc351 · 03-23-2004, 02:56

It could be done but wouldn't be worth the effort.... the power you'd make from the setup would be close to a carby fed 250 and be 3 times the cost (at least).

First thing to check is what type of 250 it is.

Non crossflow I6's have both intake and exhaust on the same side.

Crossflows have the manifolds on opposite sides of the head, but there is 2 types of head.... Iron and alloy. As for an easy way to tell which one you have I can't think of any without tearing the motor down.

Non X-flow engines can be built up with whats known as a 2V head. I've seen these engines pump out 300hp and are bloody tough low down too.

Iron head X-flows are not worth the effort. Ditch it for an alloy headed model. XE have the best blocks and the series II XF EFI heads flow the best from the factory. Put the 2 together and they can make some serious power too. Mine makes 150hp at the wheels and its my daily driver. A weekend warrior could easily pass that figure.

Also, what car are you planning on running the engine in, what tranny are you going to run and are you planning any diff mods?

Cheers,
xdc351

Pb.foot · 03-23-2004, 03:11

The reason I wanted EFI was so I could change the full input through the rev ranges by computer.

It's a X-flow (I though I already said that?

)

It's an alloy head ... I think ... I don't have viewing access right now, but the guy who has it runs it on gas, so I imagine it would be pretty dead by now if it wasn't an alloy head.

The motor is orginally out of an XD.

We are planning to run it in a Cortina, what model depends on what is cheap/available at the time.

I am completely open to suggestions are far as the driveline goes, I would prefer manual but highstall would probably be better. Some diff tweaking wouldn't go astray, but I want to make it drivable long distace (eg. 100km/h for a few hours without needing a 5000L tank.

xdc351 · 03-23-2004, 14:50

Sorry, I missed the X-flow bit!

XD's have both Iron and Alloy heads, what year XD?

A manual will be the best option for street/strip. The auto with a high stall will not be friendly on the highway. The best diff ratio will be different depending on which way you go, but a 3.45:1 would be a good compromise.

My engine in a corty would probably be well into the 14's so i'd say beating commies wouldn't be an issue. I can see why you'd want the EFI on it, but it would be a lot easier to do carby fed. Really depends on how much work/money you want to put into it!

Pb.foot · 03-26-2004, 02:33

I don't know what year the car is, but I know it's got an alloy head.

What do you think would be the best in the way of Gearbox? A 3-speed wouldn't do me justice on the highway, and a 5-speeds probably a waste of money. So, a 4-speed would be my best bet? Also, would a standard clutch handle a (sorta) worked engine?

I'll probably use a carbie, and just leave the ignition up the computer. What type of carbie do you recommend?

Thanx again

xdc351 · 03-28-2004, 17:12

4 speed manuals have the same top gear ratio as 3 speed auto's so there isn't any difference in highway driving RPM between the 2.

The reason a 5 speed is better for highway driving is the overdrive 5th gear, it'll drop your cruising RPM by 500-1000 which makes things a lot more manageable. A standard clutch would die pretty quickly with the mods your looking at... An aftermarket one would last a lot longer.

My 6 is running a 465 holley on a redline 4bbl manifold. Its just a little to big for my current setup, but nothing a more serious cam wouldn't fix.

Are you planning on making the engine mild/street/wild? The type of cam, clutch (or stall), diff gears, etc will all depend on how hot you want this engine to be.

Pb.foot · 04-13-2004, 17:33

I want to do it up as a street car, so that it can still be driven without too much fuss. I can't afford the time or money to build it up crazy, and if I was gonna do it mild why am I bothering?

I'm proably looking at a full rebuild, and decent parts in the process.

A balanced crank is a must, but I'll probably leave it the same.
I don't know what I'll need as far as the cams go.
Due to the cost, I'll probably have to stick with stock (cleaned or new) pistons.
Holley carbie of course
Extractors (What size piping would you recommend?)
New rings, bearings, blah blah
Any recommendations as far as the inlet go?

I think that's about it for the engine, so I'll leave it at that for now.

Thanx in advance

not ford · 04-14-2004, 02:47

If you are running it in a Cortina will you be keeping the 13" wheels? Reason is that the 13's with 2.92 act like 3.55 with 14" rims. Also Its hard to get decent 13" tyres.

If the car is programmed with aftermarket EFI the cams are the same to carby but you'll have more low down torque. Since you're alloy headed all the factory EFI stuff should bolt straight on.

The Holley 1850 600cfm vac sec carby is a better carby than the 465, I have tried both.

Yakumo · 04-14-2004, 05:16

I imagine I will be looking out for some decent mags, 14" hopefully.