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Discussion Starter #1
I've been debating doing something to my 289. Its a 2V converted to a 4V with a cobra intake manifold and 500 CFM Holley carb. I know nothing about the internals. I was debating going full tilt and doing an Edelbrock top end kit with new heads cam and such, but for almost $2000, not sure I want to spend that kind of money just to get a little more pep around town.


After some thought, I decided to go with @22GT recipe. Going to get a C9OZ-6250-C cam, 600 CFM carb, recurve my distributor and port match my stock heads. I'm going to put some HiPo manifolds on ( I may try to clean up my stock ones but they seem pretty rough) and keep my C4, but put a shift kit in it and possibly swap out my 2.80 gears for something a little bit peppier. ( I'll ask that question later).


Couple of questions:


1) Which cam should I get? Came across this one https://www.summitracing.com/parts/hrs-217081-13/recommendedparts/part-type/lifters
2) what about the lifters? Any recommendations? With a new cam I need to replace the lifters.

3) Do I need to change the valve springs, push rods?


The motor makes great vacuum. While I have the motor out, I'll look at the timing chain, pull one of the crank bearings and see what they look like. I'll do a little diagnosis to make sure things look good. I'd prefer NOT to get into a complete engine rebuild.



Looking for a mild street motor that's easy to drive, but with more pep than I have now.


Thanks


Peter
 

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The Howards piece is decent. You MAY want to consider screw-in studs, new valve springs, retainers and keepers. Unless you change your rocker arm style you shouldn't need to change pushrods. Running this cam I'd run HiPo exhaust manifolds and 1.7:1 rockers on the exhaust side of the same type you have now (non-rail vs. rail depending on whether your engine is +/- change level 11). This will "fool" the camshaft into thinking it has more exhaust duration which helps with the notorious exhaust deficiency of the small block head.

For lifters, I'd probably go with these....

https://www.summitracing.com/parts/rhl-9008l/overview/make/ford
 

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Discussion Starter #3
The Howards piece is decent. You MAY want to consider screw-in studs, new valve springs, retainers and keepers. Unless you change your rocker arm style you shouldn't need to change pushrods. Running this cam I'd run HiPo exhaust manifolds and 1.7:1 rockers on the exhaust side of the same type you have now (non-rail vs. rail depending on whether your engine is +/- change level 11). This will "fool" the camshaft into thinking it has more exhaust duration which helps with the notorious exhaust deficiency of the small block head.

For lifters, I'd probably go with these....

https://www.summitracing.com/parts/rhl-9008l/overview/make/ford

Thanks Woodchuck! I just googled the Ford cam number and that cam came up on Summit website. Don't know much about them. I' heard of Lunati, but i couldn't find one with those specs.


You answered more underlying questions. From reading Tom Monroe's book, i was planning on screw in rocker studs. Springs, retainers, and keepers was another question I was thinking about.


Also just to be clear, You would recommend replacing the exhaust rockers with 1.7:1 rockers and keep the intake rockers as is? If I do swap out the rockers, do i then need new exhaust push rods? If I'm doing that, why not just do all new rockers and pushrods? I kind of want to keep this as simple as possible.
 

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That is a symetrical grind cam so the 1.7 exhaust rockers would help the exhaust side exhale a bit better with respect to the inhale. Often, the cam is ground with different intake versus exhaust duration and lift for this.



Ford heads are typically a bit constricted on the exhaust side unless they are specifically made, milled or hand blended and ported to balance out the intake versus exhaust flow. The books say you want 75 to 80 percent flow ratio of exhaust to intake. I did a massive amount of port work on my heads to try and get to this because I wanted to run a symmetrical cam. On the flow bench I got 178 exhaust and 236 intake flow at .550 lift which is 75.42 percent(just using my numbers as an example).
 

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When you're ready for a cam call Howard's. They're a old, well established and respected cam company. When you call them you will get personal one on one contact listening to you. You're not getting someone reading off a scripted flow chart. You will be getting free expert advice on selecting the right camshaft for your needs. Isky cams is another well respected company you might want to touch base with. Either company will do you right.
 

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If you're going to remove the heads to install screw in-studs you may as well have the exhaust ports opened up. Of course with the screw-in studs and exhaust port work you're in the price range of aluminum heads.
 

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Discussion Starter #7
If you're going to remove the heads to install screw in-studs you may as well have the exhaust ports opened up. Of course with the screw-in studs and exhaust port work you're in the price range of aluminum heads.

I was thinking of porting the exhaust myself. If i screw it up, I can always get an aluminum head then!
 

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If you're going to remove the heads to install screw in-studs you may as well have the exhaust ports opened up. Of course with the screw-in studs and exhaust port work you're in the price range of aluminum heads.
Hmmm…
Die Grinder - Harbor Freight - $15
Grinder Burrs - Harbor Freight - $8
Studs - Summit Racing - $52

Here's an easy guide to upgrading your heads:
Port Matching

I was thinking of porting the exhaust myself. If i screw it up, I can always get an aluminum head then!
If you follow the profile originally intended for the exhaust ports, you should have very little risk.
 

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...possibly swap out my 2.80 gears for something a little bit peppier.

Definitely install a bigger gear. In fact, if it was my car, that would be the first mod I did. You'll be amazed at how much of a difference it makes. Your car will be a lot peppier around town. I would suggest a 3.55 or even a 3.70 unless you're going to do a lot of long-distance cruising on the freeway. I have a 3.70 in my car with a TKO-600. Around town, I almost never need the overdrive. I only need the overdrive when I'm on the freeway doing 70 MPH or higher. Thus, my car would be fine around town with a 3.70 and a 4-speed.
 

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When I was running a similar combination I ran the Isky version of the .448/.472 lift performer plus cam. Nice torquey cam and it worked fine for years with standard springs and studs spinning up to about 6K.
 

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Discussion Starter #11
Hmmm…
Die Grinder - Harbor Freight - $15
Grinder Burrs - Harbor Freight - $8
Studs - Summit Racing - $52

Here's an easy guide to upgrading your heads:
Port Matching


If you follow the profile originally intended for the exhaust ports, you should have very little risk.

I read that PDF before. I think I can handle that. How difficult is it to tap the head for the studs? I have a tap and die set. Should I let a machine shop do this? My taps are tapered and not flush.
 

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Ophthos, the 289 doesn't produce prodigious torque, and it sounds like you want actual 'I can feel it' performance - not 1/4 mile times. So what you are looking for is *average*, not peak power. Most cams rob your bottom end, moving peak torque production up higher (and hence, horsepower rating). Try to keep your cam modest, especially with a stock torque converter. Gears will help your 289, which doesn't mind RPMs for power production. If you drive on the highway (I drive 80 all the time on the interstates out here), I'd probably keep it to 3.25 or lower to keep RPMs reasonable. Your stock heads are going to be the biggest bottleneck for producing more torque, because their flow is fairly poor. Going to a bigger cam may give you a few more horsepower, but probably won't increase torque much until you either get your heads ported, or get better heads.

If you do get a 600 CFM carb, don't go with a Holley. Get a Summit M-series, which is a lot more like the old Autolites. Your low to midrange power will be significantly better, along with your mileage and part-throttle response.

HiPo manifolds offer very little improvement over the stock logs from what I've seen. If you have to buy a set and go through the fuss of redoing your exhaust to make this work, instead, consider a good set of Tri-Y headers, as they deliver the best overall performance for street use.

Lastly, getting your timing spot on always makes a tremendous difference. Using vacuum advance with manifold vacuum won't get you any more peak power, but it will help your car idle smoothly, run and accelerate better, and really improve your mileage too. Don't be afraid of points; up to about 5500, they deliver a big, fat, long-lasting spark that lights the mix very well.

Good luck! =)
 

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^^^
Define "good set of tri-y headers". My buddy had tri-y's installed on his Shelby to be more correct, but they choke it off at 6k vs long tube headers. I am not sure the brand of Tri-Y's, but he cannot get them off the car fast enough.

The OP should be fine with a 500cfm carb.
 

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Not trying so sound like a broken record but this is why I went to a GT40P. I have a reman 302 built by a marine shop sitting under my bench at home. The heads are those lousy 80's 69 cc no compression heads along with a stock flat tappet. I was going to buy a new flat tappet and put a set of GT40P heads that I had. I really don't need a set of aluminum heads for my use rather a set cleaned up like others say. Exhaust port clean up, a little bowl work and maybe a set of 351W valves. This is more in line what I needed and wanted. The GT40P heads are going to work about the same as the mildly worked over 289 heads. Next the cost. Well the P heads were a lot less then reworking old heads as they were new.

One day I thought, do I need a new motor? With that I sold the P heads for $525, what I paid for them. Bought a whole motor, trans and efi crap for $450. Sold off what I didn't want for $175. A big advantage of the roller cam, you can reuse the cams. You don't break in the tappets to a cam, it doesn't matter. This opens up a whole new opportunities for good used performance cams with modern up to date profiles at a steep discount over a new cam from someone who's upgraded. It actually becomes a cheaper and easier cam swap then a flat tappet cam as you have to buy new everything each time. I paid $60 for a used 5.0 Mustang cam which is roughly like a RV cam and is a pretty good stock factory cam.

I've got so little money into my motor it's not funny. It runs way better then I expected. It' pulls to 6K strongly.

Of course you won't have that one on one experience of really working on your motor either which is equally important. There really isn't any one right thing. I'm just throwing my suggestion out there simple as another idea
 

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Discussion Starter #15
Tom, I think that whole GT40 thing scares me at this time. I see where you're coming from, but I really bought this car to try and do as much by myself as I can. Its really my first adventure in working on a car. I've restored an old Triumph motorcycle before, but I've wanted to do something bigger and better. I've been able to do all my suspension stuff, rewire the under dash and engine compartment, and I think I want to do some engine work. Right now I think i can handle a cam swap and playing with my heads (giggity). I really need someone with more knowledge to help me pick all the right parts.

I've gotten some really great advise so far. I think I'll put my final list together and see what the consensus is. See if anyone thinks there should be some drastic changes or better parts.
 

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^^^
Define "good set of tri-y headers". My buddy had tri-y's installed on his Shelby to be more correct, but they choke it off at 6k vs long tube headers. I am not sure the brand of Tri-Y's, but he cannot get them off the car fast enough.

The OP should be fine with a 500cfm carb.

Compared to long-tubes, Tri-Y headers give a modest boost at midrange RPMs, and another somewhere around 5500-6500k, before - as you say - signing off. Not the best for drag racing, but since long-tubes don't offer any benefit till well over 6k typically, you kind of have to decide what kind of driving you intend to do the most. All the numbers are based on tuning, so they're a bit variable. Big takeaway is that Tri-Y is a 'modest' boost in mid AND top end, while longtubes are just one huge boost on the very top end only.
 

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Tom, I think that whole GT40 thing scares me at this time. I see where you're coming from, but I really bought this car to try and do as much by myself as I can. Its really my first adventure in working on a car. I've restored an old Triumph motorcycle before, but I've wanted to do something bigger and better. I've been able to do all my suspension stuff, rewire the under dash and engine compartment, and I think I want to do some engine work. Right now I think i can handle a cam swap and playing with my heads (giggity). I really need someone with more knowledge to help me pick all the right parts.

I've gotten some really great advise so far. I think I'll put my final list together and see what the consensus is. See if anyone thinks there should be some drastic changes or better parts.

I hear ya. I was just stating that option as one of many. I think you'll do best with your plans. These motors are totally different when they can breath better! A mild cam, open up the exhaust ports a little bit, smooth down rough edges on the valve pockets which by the way is very effective and one of the best things you can do along with a good multi angle valve job. None of this will break the bank.
 

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How difficult is it to tap the head for the studs? I have a tap and die set. Should I let a machine shop do this? My taps are tapered and not flush.

It's more involved than simply running a tap into the hole. If that's all it took you could simply buy a "bottom" tap to finish threading the holes.
After the factory rocker studs are pulled the machine shop will spot face the top of the stud pedestals to provide a perfectly flat surface for the hex part of the screw-in studs to seat onto. That's what prevents the studs from backing out. Then they will need to drill the holes with the tap drill appropriate for a 7/16"-14 thread. Then tap the holes. The drilling and tapping must be done with a vertical mill to insure that the holes and threads are perfectly square with the valves.
I have a vertical mill and I converted my Australian 302 Cleveland heads from the factory pedestals to screw-in studs. The Cleveland head has valves that are canted away from vertical in 2 directions. I spent a couple of weeks working over both heads because it was tedious getting the head of the mill set up for the compound angle and I didn't want to get in a hurry and screw up a head. That would have cost a small fortune if I had been paying a shop to do it.
 

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Besides you need high quality taps similar to what a machine shop uses. Taps like drills are very, very hard and a real bytch to get out when they break. What's sold to consumers are generally poor quality,very brittle and snap very easily
 

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Tom, I think that whole GT40 thing scares me at this time. I see where you're coming from, but I really bought this car to try and do as much by myself as I can. Its really my first adventure in working on a car. I've restored an old Triumph motorcycle before, but I've wanted to do something bigger and better. I've been able to do all my suspension stuff, rewire the under dash and engine compartment, and I think I want to do some engine work. Right now I think i can handle a cam swap and playing with my heads (giggity). I really need someone with more knowledge to help me pick all the right parts.

I've gotten some really great advise so far. I think I'll put my final list together and see what the consensus is. See if anyone thinks there should be some drastic changes or better parts.
the GT40/P engines are just as easy if not more so than an old school 289/302 to work on
 
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