Maybe time for some upgrades...Suggestions?

My car is running pretty good and I'm looking to put a few thousand into it the end of summer or early fall. I've been feeling the need for some more speed parts but not sure what order I should do things since I usually put about $1500 in the car per year. It's a '67 with a stock 289 except for a Performer RPM intake and Edelbrock Performer Carb 500 cfm which I put on last winter. It's also got all new suspension and had front disc brakes added. C4 auto that shifts fine and doesn't leak, and 8" rear with 2.79 ratio and open diff.

I'd like suggestions on what I should possibly do first. I know power adders will put stress on the weaker parts and know I will have to upgrade or rebuild tranny and rear end to handle much power. I was thinking about gears first, but then started thinking about limited slip or some variation too and then all the sudden I'm looking at quite a bit of money dropped into a stock 8" differential.

I do understand I might be doing double the labor/cost adding parts that aren't part of my final plan for the car, but I'd like to make it more fun to drive in the mean time. It might take 10 years to get the drivetrain I'd really want and paint, interior, etc. all finished. Thanks for the info in advance.
 
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That 3rd member setup might be able to take 550hp but If you plan on over 350 hp eventually then I'd skip upgrading the 8" as once you get a little more power than that the axles also become a weak link (assuming you're going to run sticky tires or launch it on the dragstrip) and even upgrading to aftermarket axles might get you the ability to reliably run a 500hp engine - if it's strictly a boulevard cruiser that runs skinnier street tires then the axles won't see the stress. I'd look for a good used 9" and install that as the cost and parts are in a lot of cases cheaper than the 8" stuff from what I've found - if you want a cheap strong setup - get a bare 9" housing to fit the mustang, look in some of the pickups for 3.50 limited slip 3rd members with 31 spline axles and then get some aftermarket 31 spline axles or have the pickup ones cut down and re-drill the bolt pattern to fit the small ford pattern. Also - before deciding on a rear axle ratio - decide if you're going to stick with a non-OD non-lockup transmission or go to a modern OD transmission with lockup or convert to a manual transmission...

Are you planning on running that 289 or are you thinking long term of making bigger power and going with a 351W / 393 or other big block? Need to decide if you'll be happy with the power that a 289 can make or you're going to step it up and build a larger engine.

One thing I'd do to 'get by' with a little more for now and not spend a ton of money if it's not in your long term interest/goals is put a shift kit in the trans and firm up the shifts (under $100 and an easy one night job), install a ~2800-3200 RPM stall converter and that will really wake up the acceleration - then if that's a 'regular' 289 you can put a cam in it for ~$150-up to make some more power and then you can work on the rest of the package.
 
Good points, all, but with a 10 year schedule and a $1500 a year budget, gears will wake up his stock 289 now and with a 2.46 first gear in that C4, the 2.79's are giving him an SLR of less than 7. Not really performance territory Even a 3.55 would only provide an 8.7. Maybe he should consider BOTH gears and OD before too many engine mods !
 
Well thinking about it - if I was going to stick with the 289 here's what I'd do with $1500 to get the best bang for the buck
Gt40 (not P) heads - $300 +- depending on condition - find some that don't need a valve job
Gasket set - $60
flat tappet camshaft and lifter set (from ~$100-300)
Flowtech or other budget headers - $130
AOD transmission - $200-300 used in good shape (get the block-plate, flexplate, TV cable, mount and converter - and driveshaft yoke from seller)
AOD shift kit $80
AOD 2800-3200 stall converter $225-300

That assumes you can do the labor yourself and some minor fab work (i.e. crossmember) and then next year address the gear/traction problem. The AOD has close to the same 1/2/3rd ratios but you gain OD - not a concern with the rear you have now but when you upgrade you can go with a 3.80-4.10 ratio and have a real good setup that maintains highway cruise comfort.
 
I think all of these are good options and I've got a bit of time before I have to decide on anything. I've spent the last 3 years replacing parts that were worn out and now that it's reliable I can focus more on performance. I've looked at AODs before and that would be my ideal option as well as gears in the 3.73-4.10 range. My goal is to eventually do a 331-347 engine. I've read about the gt40 heads before and might start looking for some. I don't mind doing some of the work myself but without a shop some of it will be difficult to do in a one car garage. I've finished the top end of a Chevy short block before with the help of a mechanic and rebuilt a few carbs but nothing besides maintenance and basic parts. I've got a good mechanic that always helps out and is knowledgeable though so if I have to pay labor it will be worth it.
 
GT40 heads don't flow enough for a 331/347 stroker - given that's your goal - I'd concentrate on swapping the trans out, rear end work, and exhaust - all of it will be re-used with a stroker... Next year buy some aluminum heads with the $1500, put them on the 289 (match them for the flow of the 331/347 - which will be overkill on the smaller cubes but will be real necessary for the bigger engine) and then save up for the stroker short block and do that next.
 
GT40 heads don't flow enough for a 331/347 stroker - given that's your goal - I'd concentrate on swapping the trans out, rear end work, and exhaust - all of it will be re-used with a stroker... Next year buy some aluminum heads with the $1500, put them on the 289 (match them for the flow of the 331/347 - which will be overkill on the smaller cubes but will be real necessary for the bigger engine) and then save up for the stroker short block and do that next.
well said... do not buy gt40 or any other ford performance part for that matter. spend an entire years investment on quality cylinder heads. you will be glad you did. good heads is the best improvement to a sbf. forget about any other engine modification until you have heads.