Building the 250 thats right for me...

[lahti35]

As I gather parts to make the 250 swap in my '61 falcon I'm faced with a number of questions and decisions... What I'm after is a nice street motor with some get up and go and a nice burble at the exhaust on a budget. This will be mated to a toploader 3 speed.

Things I will be doing: Milling the manifold flat and opening the intake hole for a Webber DVG and adaptor. Shaving the head a bit for some extra compression (target not known at this time but just a small bump, nothing crazy). Headers for sure and forged rods with arp studs.

Things I'm fuzzy on.... ignition/distributor? What kind of cam shaft? Single or dual exhaust system for the above package?...

That's where I can use a hand to put together a nice solid engine that will pull my little '61 along better than the worn out 144.

P.S. Things I won't be doing: aluminum heads, turbo, and blingy performance upgrades... my family has to eat.

 

[bmbm40]

For the ignition you could get a DSII from wsa111. He has rebuilt units and will put the curve on it that you need.
Have you considered a T5? The od will give you comfortable cruising on the highway. Mile after mile. And then you get the close ratio four speed for the non highway use.In my opinion a five speed/od is for the money within the realm of the direct mount in terms of performance increase.

 

[powerband]

The 250 in a 61 is a great upgrade to drivability and performance. The Toploader 3spd is plenty strong enough although help to match rear axle ratio to your purposes. The OEM '61 rear is probably @ 3.50 :1 , suitable for performance but not modern HiWay speeds - for long... . The 250 cars (Mav, Granada, Mustang...) used high gears - typically @ 2.79:1 ratio for the needed interstate speeds in the 70's. the 250 has enough torque to still pull with high rear ratios but suffers its performance . A 250 with an OverDrive transmission with a LOW geared rear can enable both performance and modern driving speeds. I ran a 250/Toploader in my '61 for a while with the OEM 3.50:1 rear and used the original 61 3OTT linkage until later Maverick rear and T5 upgrades.

The 250 used the DS-II electronic igniton / Distrib after @ '71 and can be good for performance even when unmodified. With proper setup and tuning it is fine unless maximum performance is needed.

have fun, build what you want , can afford or have access to ...


. .



Blueprinted D6DE Ford small block 250 Six; Shot Peened and Balanced Rods, Clifford 272H Cam, 1.88 intake valves/1.50 exh with- silicon springs and HD retainers, Ported and Polished chambers and relieved valve shrouds .Fisher custom Harmonic Balancer, Tri-Power / Offy , Modified Holley carbs, Exhaust ¾ siamese port divider, Re-Curved distributor, HEI ignition, Indexed Champion plugs, Glyptal sealed block, Detroit gasket set,. SFI 157 neutral balance-lightened flywheel spinning Centerforce Clutch, T5-Z Cobra 5speed, Short throw Hurst shifter, 8”- 3.80:1 TracLoc Posi rear, Fab'd Caltrac clones, Shelby sway bars, Mustang front strut bars, Scarebird Disc front brakes, Fabricated subframe connectors / crossmembers, 8 Point roll cage, 5.0 alum. radiator, Perma-Cool fan, Holley fuel pump/pressure regulators, Hooker dual out longtube headers, Smithy silencers, Original tube radio, vacuum wipers and front fender Gunsights…

 

[lahti35]

The original rear end in my '61 is a 3.10, combined with the 144 I could watch the grass grow while accelerating!

OD is out, I want to keep the column shifter for now. Its part of the charm of the old bird and her floors are original in excellent condition with the original rubber mat... I am not ready to cut through them yet.

I'm just basically looking for more power with the same setup I had before with the option of changing the from the upgraded 3 speed toploader and 8" 2.79 rear end gears later. I've already sourced a early maverick 8" for the rear, working on a 3 speed.

A DSII from wsa111 sounds like the most prudent way to go for the application so I think that's solved.

Concerning a cam... what's out there that would give me a little more low end grunt with the modified log/webber 2v/headers/and a slight bump in compression?

 

[chad]

"...bump in compression…"
to…?
Still use 87 octane?

I know "daily driver" is scribed on the line - is that a true mix? of hiway, 2 lane, interstate, stop'n go? Where, in general, do U live?

Do you have that progressive carb yet?
Glad U wont stick w/the feedback system. Don't forget the ford module (Blue strain relief) w/that DSII distrub. and an oil filled coil.

Congrats on the vehicle, sounds like a real charm!

Cam's next, go slo, let's C...

 

[lahti35]

"...bump in compression…"
to…?
Still use 87 octane?

I know "daily driver" is scribed on the line - is that a true mix? of hiway, 2 lane, interstate, stop'n go? Where, in general, do U live?

Do you have that progressive carb yet?

Compression ratio bumped up to 9.5:1 so I can use regular gas...

Before the 144 died I used the car for daily transportation, mostly on back roads at 55-60mph and city stop and go traffic. Its almost totally flat around here, no hills n' stuff. Mid Michigan has boring terrain.

I'll be using a webber 2v progressive carb with the adapter from classic inlines (they still have a few adaptors left, I ordered on this AM).

 

[CZLN6]

Howdy Lahti and All:

I'll throw in my two cents on your build. I built my 250 for my '65 Ranchero around a Comp 260 cam. This was pre-Classic Inlines, which, unfortunately is no longer an option. I choose the Comp 260 because of lift of .440", decent vacuum and affordability. It runs strong to five grand and fairly good bottom with a 9.5:1 CR and a single outlet header.

The cam was complimented with a D8 head cast with stock 1.75" intake valves with a performance three angle seat and a top back-cut. I used the intake valves from a 144 engine for exhaust valves on the 250 head. I polished the chambers, pocket ported the intake and spent more time on porting the exhaust along with installing a port divider. I used stock valve springs shimmed .030".

I used a Clifford Performance single outlet header that was designed for the slightly taller 250 block but still had to modify it for starter clearance. I also had it HPC coated to make it last. I have seen a header on Ebay that looked good but have not heard of anyone with first hand experience with them. I choose to go single exhaust for several reasons; less expensive, lighter weight, easier fitment, Less prone to rust out with light, occasional use. I choose a Walker Dyno-Max turbo type muffler- good performance, good sound and not too loud. I used a 2" exhaust system after the muffler. Dual exhaust has a higher coolness factor and may offer better high rpm performance but at a premium price wise.

The DS II is the way to go, IMHO for several reasons- cost, reliability and tuneability. I'd suggest that you upgrade with an MSD Blaster coil for a hotter spark and a recurve tailored to your engine, drive train and elevation. That's what I did.

You will find that the 250 and bell housing is larger and will require some modification of the radiator support, firewall and transmission hump to accommodate. The new engine/trans is longer and taller. Well, not the engine, but the water pump/crank pulleys.

That's my experiences and choices, for what it's worth. I'll be following your progress.

Adios, David