A friend of mine and myself have a couple of O/T cars that we race against each other for fun. His is a '65 Chevelle four door wagon with a stock 283 with a two barrel, single exhaust and 3.08 gears with a Factory Muncie 4 speed. It has 90,000 miles on it. Mine is a '67 Falcon 4 door wagon with a stock 289 with a two barrel, single exhaust and 3.00 gears with a C-4 tranny. It has 81,000 miles on it. I usually pull him off the line bad, but he comes on strong in the mid range and beats me by a car length of two. Our rules are that the engines have to be stock appearing and sounding, but any other mods are ok. We check the strokes of the engines, so a bigger stroke is out of the question. I want to port the intake manifold, heads and exhaust manifolds to free up a few ponies. How much of a HP difference will porting everything make? Changing cams is also illegal.
not sure, the idea is to increase efficientcy.Do some research, gasket match the intake and exaust ports. clean up the rough sand castings in the intake runners. polish the exaust ports and domes. personally i would help my friend with his build up, and compete with others..makeing rulles and checking out each other per rules seems strange
Get a set of gt40 or gt40p heads from a wrecker. They are on explorers up till 2001. I have installed a set of 5.0l mustang heads that had a mild exhaust porting job on an earlier (70's) 302 and they bolted up and had the hardened seats. I used the later pushrods and rockers on the early short block. Hope that helps.
you are working on the wrong end of the car. lighten the car , is the front end aligned. make the car roll easy. have you repacked your front wheel bearings. changed your rearend oil. basic tuneup. you can learn a ton of things making a underpowered car go fast. get different rear tires. different ratio tires can effect your driveline ratio in a huge way. think outside the box look at the whole car. if it weighs less and rolls easier. it will go way quicker and way faster. find lbs and hps in different places on the car rather than under the hood
Type in "ford 289 head porting" on youtube. There are some demo videos on porting guys have done with 289 and 302s. If you keep the 2 barrel, I might recommend just doing some port matching, clean up the intake side and polish the exhaust side. There are also some things you can do to the combustion chamber to get better swirl (I've read that this is a major weakness of the SBF and has the potential to unlock some ponies). I think if you get into changing your intake runner volumes too much, you won't get the benefit with the stock cam and 2 barrel carb.
Lightening the car is out of the question as it is still a cruiser that I use all the time. The car is tuned really well, alignment done, air pressure is high in the front tires. Brakes have zero drag, synthetic oil in the engine, trans and diff. I'm keeping the 3.00 gears as I still drive the car long distances. It is just a grudge thing between friends to see who has the fastest "stock" wagon.
I also lightened the car some by going to a Ford PMGR starter, an aluminum water pump, aluminum E.T. Mags, removing the spare and jack. I also have a belt that turns the water pump and alternator only, bypassing the A/C compressor and power steering pump. I have a switch that kills the alternator when racing as well.
Go to the distributor and make sure you are getting full advance around 26 to 2800 rpm. Run prem gas and run as much advance as you can without rattling the valves. Look into an electric fan if that is permissible. Put a low restriction muffler or no muff if you can stand it., might want to exit it out the side instead of over the axle. If you go the gt 40 heads check you comb chamber cc's. You do not want to reduce it. Make sure the gas pedal opens the carb all the way. Put an open air filter on it. If you can put some fiberboard, something like the old door panels were made of, from the front bumper as far back as possible. This will really help on the upper end. Real good cardboard will work temporarly. Run different heights of tires on the rear. You are already beating him out of the hole, a little taller tire may keep you ahead. Narrow tires have less rolling resistance. Put a 1" spacer under the carb. Use one that is pretty solid, do not want to break of the ears on the base plate. If you could find a 2 barrel carb off a 390, or maybe even a 351, it should give you a liitle more air. This will be fun. Is he reading the same post?
With a 2 barrel and stock cam, I doubt you are running out of cylinder head. As others have said, if everything else is up to par, (timing, jetting, etc) then I would look at maximizing weight loss.
Take the heads off and open up the exhaust ports. What you want to get rid of are the thermactor humps. Don't get too aggressive as the humps can get you into the water jacket... bad... The suggestion above for GT-40 or GT40 P heads would be a good cheap alternative if you were running a 302. The additional chamber volumn of these late model heads is about 64 cc (60cc were only one year of head the F3ZZ head from '93). On your 289 you will be giving up too much in the form of compression to get any benefit from the GT40/GT40P head. Port those 289 heads, hopefully they are the small chamber, put in a better cam, check the flywts in the distributor (to now what their advance curve will be), put in some light springs, figure no more than 36-38 deg "total" advance all in by 2000-2500 (you may see an initial of about 14-18 deg.) bolt on a good 500cfm 2bbl, and it will be a whole different engine. Never spin it past about 5500 to 6000 (stock rod bolts are weak) and you will be good to go. Good luck! Tom
Porting - 1. Clean the entire port (int & exh.) of roughness in the surface. 2. Open the ports (all) to the gasket dimension. 3. Smooth all lumps and bumps. That is, head bolt boss, the Thermactor (smog) humps in the exhaust. I've done a few Fords, and as I recall, you can remove them completely (BUT...do at your own risk !). 4. Clean ALL sharp edges from around the valves, blend to a large radius where ever possible. 5. Round the "short turn" radius as best you can. 6. Smooth the back of the bowls (just under the valve). 7. A proper...three angle valve grind is WELL worth the money. 8. Remove any directional changes within the port. The gas (both !) should follow a nice smooth, straight path to the valve. Note: Do NOT polish the intake port. You can polish the exhaust if you like, but smooth is fine. That should get you started. Wear eye and hearing protection. Mike
He is right . if they check add shavings from a brake lathe to the paint don't ask me how I know this . You are carb and exhaust limited as well . For a port job gasket match on both side and taper in 1 inch into the head,. do the same to the intake and exhaust manifolds . look at doing running better gas even race gas and 36 degrees total advance in the timing .
Buy this book........."Air Flow And How To Get It"......study it, before doing anything to a head.........(amazon has it)
There was a guy I knew, back in the '70's. He had a Gremlin X with the 304. Basically, he degreed the cam, ran a free flowing dual exhaust, dyno tuned it and shimmed the carrier to hook up posi. The car ran 13.0's. The guys than ran the stock classes at the drags were wizards with tuning.
This is good advice. I wouldn't worry too much about porting the heads or going to GT40's and what not. The `67 289 heads are pretty well matched to the cubes. Ignition curve, carb CFM and restrictive exhaust manifolds are the biggest power limiters you have. If you port anything get some larger volume truck 351W exhaust manifolds and port the entrance so it compliments and does not restrict the exhaust port in the heads. Put in good fresh valvesprings and let her wind. Pay some attention to the C4 and your 1/2 shift. There is an easy mod in the valvebody that will really give you a nice firm and less energy wasting 1/2 shift by simply removing a check ball if memory serves me correctly. You can probably search the web and find it. I had the trans tech at our shop put a snap band in an old 302 Granada I had, and he did the mod for me. The thing would bark the tires on the 1/2 shift if I got on it. Totally stock engine. Made it feel way less lazy.
I got ahead of myself and I forgot to mention that before you do anything that costs money, do an evaluation of the condition of your engine. A leak down test or at least a compression test should be your first move. No sense in wasting time or money if you have a weak cyl or two. If you do decide to pull the heads and port, focus on the valve pockets and blend them into a good valve job. Mill the heads a bit to tighten up the combustion chambers and raise compression. This will give you a ton of bang for your buck.
Porting the heads and keeping the stock cam/exhaust/3.0 gears is a waste of time and money. Sorry, try it if you like.
Heres a really good article on getting 400hp out of a 289/302cu Ford: http://www.mustangandfords.com/techarticles/engine/28898_400_hp_302_small_block/index.html Joe Sherman knows how to make power with these engines with stock parts. Rotating the piston 180deg on the rod, to gain a longer lever is brilliant. I've built a few OT Mustangs over the years using his recipe and they hauled ass. Take bumps out of the exhaust ports and work the bowls intake and exh. Gasket match the int and ex ports. 1.84 int and 1.54 ex valves from a GT40 head is a good upgrade for your 289 heads if you have the extra money to spend for that, and good valve job. 289 heads have 54cc combustion chambers stock. Can mill the heads to get the compression up some also.
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