Ford Muscle Cars Tech Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
Okay guys I'm new on here, but i have a 1974 Maverick with the 250 i6 and C4 trans. Motor runs great but i feel like i want more out of the car as a whole. So my question is should i keep the i6 and just build it up until I'm happy or should I go through all the twist, turns, cuts, welds, and other swaps to put a 351w that i already have bored over in it. I came to the forum to ask you guys because I am at a serious crossroads here with this choice. All the race car builders in the area are telling me that i should build up the 250 because it can reach the same level as a V8, but i want to have real power, and those answers would come better from a fellow Maverick enthusiast i feel. So please let me know what would be worth it in the end.
 

·
Registered
Joined
·
1,045 Posts
The Ford inline 6 can be made to run very well.
They are capable of making great power,and are known for making excellent torque.
Some may disagree, but IMHO, on the street, torque rules!
Torque is what moves the car.
Horsepower is just a number calculated from torque.

Look what PowerNation did with a Ford 6, granted, it's a 300 CID
but the "little" 250 can also be made to run and lots of aftermarket stuff available for it.



If it were my car, I 'd keep the 6 and build it up.

.
 

·
Registered
Joined
·
10,319 Posts
… but i want to have real power …
You can get 101 answers with that vague statement, but only a couple will be right or satisfying for you. In order to zero-in on a better answer, please provide what "real power" means to you, why you want it, how you will use it, what budget you have, etc. Only then can anyone make realistic suggestions that will fit your needs, not only for the engine package, but for the supporting parts (drivetrain, cooling, braking, safety equipments, etc) also required to apply and enjoy it.
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #4 · (Edited)
Thank you for your input. I feel like that's what I'm going to do. I've done research on the swap and i think that it would be more beneficial to just build it up from where its at, and thank you for the inclusion of the videos. I feel like they helped me make the decision just seeing the simple swaps that can make a difference. This car is going to be pretty much all street but i would like to try and take it to shows and turn heads, not for competition.

As far as the real power comment i made in my initial post, i was referring to the comparison of the torque and hp that i could get from a built V8 vs built i6. My dad had the grabber 302 when i was young and it was my favorite car we ever had, i want my finish build to be better than the performance he got from it.
 

·
Registered
Joined
·
10,319 Posts
As far as the real power comment i made in my initial post, i was referring to the comparison of the torque and hp that i could get from a built V8 vs built i6. My dad had the grabber 302 when i was young and it was my favorite car we ever had, i want my finish build to be better than the performance he got from it.
Thank you, and that's one piece of the puzzle for direction. While we do not have scope or goals for much of it (budget, time, skills, preferences, etc), I will offer a path or two with different scopes, cost, and results.

I have a soft spot for original features such as the engine type. If I want a modern ride, comforts and a Coyote 5.0L, I'll just buy a newer Mustang. So, blending original with my desire for impressive power and willingness to "be different"—yet make all mods reversible—I might do a popular set of upgrades as several others have done around here; a boosted straight-6. A few of the reasons are better-than V8 power, many options, easier, and if you're some level of DIY—much lower cost.

For an example, I have done a lot of this type of design work (conversion turbos, superchargers, custom EFI, etc), and I've calculated your engine for an example using stock baseline. The 1970 250 Ford is rated 155hp/240tq stock (the later 98hp rating would work equally well). The venerable 289 K-code HiPo is rated 271hp/312tq. Is that a good initial goal for "built V8"? If so, a 250 with minor mods and a centrifugal supercharger, turbo or two small twins at 10 psig on street pump gas would make about 277hp/291tq @5000 — not at 6 or 7000 rpm. It will blow right past stock Maverick V8 rated power at half that boost.

Relative power calculations from stock and on 10 psig boost (click to expand):

1968_Ford_250_stock&10_psig.jpg

This is all simply an increase in air and fuel flow like NA mods, but less rpm, retaining reliability or reducing cost. A cam and bit of head-work would push that over 300 without increasing boost. Don't forget to add cost of upgrades for brakes, exhaust, cooling, transmission and rear axle, minimum. Same as you'd do for NA.

That's stock, with turbo manifold, upgraded or reworked intake with EFI, blueprinted oil pump, fresh valve springs and gapped rings at a soft 5000 rpm limit, so stock handles it well. Having done something similar, a stock 302 (205hp), turbo and those changes (including water-air intercooler, fuel system, beefed 4R70 4-speed OD auto trans upgrade, etc) ran me $2700 total, plus my labor. The 250 could be less. It made 423hp on a 91 octane street tune (3hp short of calculated) and with a better power band (higher average power) than anything NA at the same peak power.

With boost, you retain the strong stock low-rpm torque, but then increase it a LOT (rather than stock decrease) as rpm rise. Because it's boost, the rpm and stress are much lower than a similarly-powerful NA engine at higher rev's and the high parts cost to achieve that. The tuning process and skills for EFI are the same concepts as carbs, but fuel and ignition for both power and street reliability is much easier and quicker than carbs and distributor weights.

Yes, the 302 made much more power than your six would at the same levels, but that also highlights the starting point of more cubes, and your uphill battle to make "built V8" power from a smaller six using more traditional methods. Likewise, you can optionally decrease power :p with a click or knob, or increase power with adjustment and no new parts, by increasing fuel grade and cranking-up the boost; an option not possible with other methods. The 250 with a fuel upgrade (octane blend or E85 or water injection) would do right at 325hp/390tq on 15 psi (and still 5000 rpm!), and more with intake and head mods. You may want to add hyper or forged pistons if you plan to do that a lot. Could you do the 250 cheaper? Absolutely, such as I could have done the 302 with an air-air, a built C4/C5 (no $500 trans controller), EFI controller build and stock-style fuel system parts suitable for the new power for about $1800-2000.

I'm not trying ot convince you of any path, but rather offer options you may not have considered or with more info. Now, we could next outline a good NA build that will make similar power; but do you prefer that direction, with those compromises, or enough DIY skills to avoid a home mortagage? This is why I asked the questions, as the responses can be completely different based on that info from you. It's a lot easier to know what you want or don't, than presenting multiple paths you may not be interested in, or miss one that would have been golden. It's your car and your smiles—do your thing!
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #7 ·
Thank you, and that's one piece of the puzzle for direction. While we do not have scope or goals for much of it (budget, time, skills, preferences, etc), I will offer a path or two with different scopes, cost, and results.
Thank you for all of that information! As far as the scope and goals, my budget bounces back and forth between low and high every couple months. Right now im in a high budget time (but only because i haven't came across anything or anyone that needs financial help), i plan on starting the work on it about mid spring and other than that the time frame for completion isn't a concern but i would prefer to do things in smaller increments. I really like that stats you gave me towards the charged 250, and i think im going to go that route. What would you suggest in the line of how to go about the transmission. As far as skills, cars isn't my profession but im good at figuring things out smartly, and i work on military jets so i know my way around a toolbox.

I really appreciate that response
 

·
Registered
Joined
·
10,319 Posts
The power you're seeking is within the realm of a basically stock V8 C4 build with minor mods for power and performance. For that, I'd follow the C4 build section on these forums for good results. If using auto-shifting with a vacuum modulator, you'll need to add a check valve and tee to handle the boost signal. No biggie. Don't forget to plan all the upgrades to handle and use the new power, such as U-joints and brakes, etc. Set a plan and follow it. Have fun!
 
1 - 9 of 9 Posts
Top