I'm thinking about upgrading my 250 inline but wouldn't it just make it a torque monster because I still want power to kick some import butt. So tell me about the difference if you can and can you help steer me the right way for upgrading my inline. Thanks guys
Torque is what moves the car, horsepower is what keeps it going. Those inline imports are notorious for having top end mph, because they love to rev to 7-9K. And because they usually have wide 5 speeds. I'd be so fun to rev an old school six like that haha, but no one makes a cam that allows you to rev that high. Another thing about imports is that most are light as hell, so they'll only need half your HP to keep up with you. It also depends in your area, out here we have some fast ones. Like fast enough to be outlaw 10.5 cars....but in other parts of the country they're just jokes. Which i'm sure everyone will soon be talking bout....or bashing on.
Like Alex said, that engine just won't rev enough to get a lot of peak HP. You have to do what you can with it and use the torque(something imports lack) of the 250ci to your advantage in quicker take off and the fact you won't have to downshift to stay in your powerband as often. An aussie head or a 302 conversion would take care of that too but http://fordsix.com/ and http://classicinlines.com/ have alot of parts and good info. Some other guys here have also had success with these but it can get pricey to get a lot of power.
if I remember right the '74 250 wasn't the best for performance.. Might wanna try an earlier 250 if you go that route. Anybody confirm this or shoot it down?
One thing that you need to remember in the hp difference between early and later 250 sixes is that in about 73 the automotive industry changed the way they figured hp. They went from flywheel hp to rear wheel or brake hp. This accounts for most of the difference in the hp numbers. They also dropped the compression and added smog control junk also. By 76, 77 some of the smog stuff was changing for the better and I believe they also made some minor changes to the flow caracteristics of the head, so the hp ratings started to increase a little. You can make some minor changes to help a little by advancing the timing a little and changing the timing curve in the distributer by making some spring changes giving quicker full advance. Less restrictive exhaust will also help but the bigest limmiter is the intake. To really increase it takes more fuel. It depends on how much you want as to how much you spend.
Starting in 1973 Ford changed the timing gear for emissions, it retarded the timing, dropping Horsepower and lowered gas mileage! A timing gear for a '72 or older car will really help.
like my 74' 250 has beaten my friends 72' 250 but thats after my new carb and replaced my gaskets and stuff but nothing big yet and the carb is just a simple 2brl
by the end of summer my 250 inline will be redone and hopefully one of the best redone im gonna be blowing all my pay checks on this luckly im 17 so i dont have to pay for any bills or anything
I'm very intrigued by the sixes, because of their low rpm torque, in a highway car application. On the highway, in a highway geared car, it's rare to ever exceed 3,000 rpms, and I'm usually around 2200 - 2600 rpms. So when you're going up a long grade or accelerating of the line, where do want your peak HP to be??? When you rebuild that 2- fitty have the compression as high as possible with pump gas, dont do a stock rebuild.... spending 10,000 is easy on that motor.. it's main problem is compression, and getting the air in and out. Bummer intake is one piece with the head, I decided to NOT buy the aluminum head and milled down the iron stock one and put a lil 2 barrel on it. Still haven't found the exhaust yet. The motor is a workhorse, not a racehorse. if you want to get a 302 you'll spend a lot less to make peak HP. The 250 gets about the same MPG as the 302 as well... which was Ford failure....not what they had in mind. If you want to slaughter all imports (and all else for that matter)get a big block. Seriously... I had a VW Bus back in the day fully race rigged.. I had about 7,000 in that engine and when I finally crashed it and bought a Econoline with a 351W it was faster... no replacement for displac.. well you know. I had my 6 cyl fantasies but it'd be horrifically expensive to make up for the lack of cubic inches.
My buddy had picked up an '80 Mustang for a 460 transplant. We decided it would be fun rev the 200 to death. After about an hour at 5000+ rpm's, it ran out of gas. We couldn't kill it. So, what it lacks in HP, it definitely makes up for in durability! I love the inlines!
Seven main bearing will do that I think the highest hydraulic cam that anyone makes only goes up to 6,800RPM But there's some Solid 292 112* cams available thats should make power up to 7,200 RPM And the six cylinders have a shaft rocker setup so you know they'll be safe to rev that high In one of the old books (can't remember which one) an old Falcon Six Guru said these engines can be race driven safely to 7K I'd be awesome to have a high comp high reeving Ford six! But then the crappy head will hold you back.
I love threads like this, and especially with younger guys just starting to get into cars.............................I'm 65 and have been building cars/drive trains for most of my life................at least 50 years. I started out with a 1955 Corvette 6 banger in my 52 Chevy Htp..............and back in the day I could really spank those early 265ci V8 Chevy's through the 1/8 mile and some early 283's............I spent a lot of time and money on that motor, a lot of head work, tripower, headers, gears.............went through countless 3spd transmissions..............then moved into Super Stock racing with a 1968 Camaro, 427 Light weight Galaxie, then 428 CJ Mustang, and also played with a 2.3L Ford Turbo motor in my 1988 Thunderbird.............the one thing to keep in mind here is it cost big bucks to make big HP.......and there is always going to be someone out there that has more HP and goes faster, because they can afford it......................... One of the most important parts of a motor.............although everything has to work together just perfect to make Monster Torque/HP.......is the head(s). The bottom end of most six's have 7 main bearings............which eliminates a lot of twisting and keeps the crank very straight because of all the supports..................the rods and pistons are a weak link..........and the head is just mostly junk..................(for making serious HP)............so if you start planning this build, take a look at what InjectedMav said and the sites he suggested. Now with that said, I love six cyd's..............but in all reality..............it takes about the same amount of money to make a 400hp Six as it does to make a 700hp V8.................just to put it in perspective..................and that's what it takes to get my Maverick down the 1/4 mile in the 9's. Let me qualify that my Maverick with me in the drivers seat weighs 3350lbs. So, I am not trying to discourage you from building a killer six cyd, I'm just trying to give you some insight into what it will cost you. Personally, if I was going to build a "Rice Eater" killer..............I would turbo charge the motor. IMHO
I almost forgot! Maverick75 was talking about the SHO Ford motor............and I have a short story about the motor. I actually had a 1995 (last year of the V6) SHO Tauras with auto...........and I loved that car and drove it to death. I had a friend that worked at the motor development department at Ford during the early 90's........................Ford actually sent the short block to Yamaha in Japan for development of the SHO V6...............I think it was 89 or 90..................anyway when the motor got shipped back to good ole Detroit my friend was one of the first engineers to actually put the motor on the dyno and see what it would do. After most of the testing was done they wanted to see what it would take to destroy the motor (RPM + time) and ran it a wide open throttle(no rev limiter), the motor was a little of 12,500rpm and after almost an hour they decided to turn it off not because of any issues other than they just couldn't stand the noise any longer. Upon tearing the motor down the only issue was with the bearings...........the oiling system was just not quite up to the task, but my friend told me that if the motor would have been converted to dry sump with a better oil pump it would have probably been ok. Just a little history on this fantastic motor...............Oh, one other thing..... Ford rated the automatice motor at 225HP.............it was more like 275HP, but the factory exhaust was the limiting factor here.
