65 289 A-code (Cam and Valvetrain) Questions

[maybe2fast]

Okay. My Dad and I just started on our 1965 Mustang Convertible A-code.

My Dad has always been very strict on how the car needs to be factory with no aftermarket. Now, the car is never going to be a show winner but, he finally gave in and has allowed me to do some performance mods to the car as long as the motor looks and for the most part sounds stock.

My first thoughts were a cam and rockers. Now I will need a cam with a high lobe separation so the car doesn't have a big choppy idle but will make more power than the stock camshaft.

As for rockers is there a way to use more modern rocker arms from a newer 5.0 mustang roller motors? Again they need to be able to fit under the factory valve covers. I understand that the valve springs will need to be better that's not an issue.

I know I can deck the heads and port and polish them. Free HP...

But I am looking for a cam that will have a good idle but make some nice power. with some roller rockers to compliment the cam under the factory valve covers. Also is there some good lifters that anyone would suggest.

 

[68RCodeConv]

I realize that this does not answer your question but the best "invisible" performance improvement is changing the rear gears. Going from a 2.79 to a 3.25 or 3.55 rear gear will make a big difference.

If money is no object then stroke the short block to a 347 and use aluminum heads (painted blue) with HiPo exhaust manifolds. That's what I did to my Shelby. It makes tons of power and when I open the hood everybody assumes that it is dead stock.

 

[htwheelz67]

I believe the a code is the 4bbl version, to tkae advantage of the 10.1 compression ratio you want a cam with about 214-220 duration on the int @0.50, I would look into the comp XE grinds, even the bigger grinds are tame acting compared to their specs, as far as rockers you will have to install screw in studs and guideplates to run any aftermarket rocker, the late 5.0's used a completely different bolt down rocker, you could always run later model heads as they are better than the early heads. A larger cam will tame your compression ratio, as far as LCA run 108 to 112 max. you dont want a wide like 114 lca on that eng as it will kill power. If you want something that will work great on what you have you may want to go custom cam if you want to keep it all stock looking, use the stock int, carb, rockers etc.

 

[D.Hearne]

I believe the a code is the 4bbl version, to tkae advantage of the 10.1 compression ratio you want a cam with about 214-220 duration on the int @0.50, I would look into the comp XE grinds, even the bigger grinds are tame acting compared to their specs, as far as rockers you will have to install screw in studs and guideplates to run any aftermarket rocker, the late 5.0's used a completely different bolt down rocker, you could always run later model heads as they are better than the early heads. A larger cam will tame your compression ratio, as far as LCA run 108 to 112 max. you dont want a wide like 114 lca on that eng as it will kill power. If you want something that will work great on what you have you may want to go custom cam if you want to keep it all stock looking, use the stock int, carb, rockers etc.

Based on his requirements, the Comp Cams XE's are out, the stock pressed in studs won't work with these cams. His Dad likely doesn't want to swap heads, so that's out as well. Most roller rockers won't clear the oil baffles in the stock height valve covers, replacement covers can be found to cure this, or dimple the baffles in the stock covers. A wide LSA does not kill power, nothing could be further from the truth. I'm running wide LSA cams and there's no shortage of power in them. They give the best of both worlds---power and mileage and cleaner emissions. They will however, not compliment the 10 to 1 comp ratio, unless they're planning on running pump premium, which they're probably doing now anyway with the stock cam. A good compromise would be a complete rework of the stock heads (new larger valves, porting and studs, or buy a set already done ) then choosing something like an RV type cam (204-214 to 214-224 duration and a .450-500 lift) Top it off with a Ford A321, Edelbrock F4B or a Shelby "Cobra" high rise and a Holley carb (this will keep the "stock" looking theme but give it some breathing room) The add some Tri-Y headers to help the exhaust.

 

[maybe2fast]

as long as it looks stock from the outside we are okay.

however it has to sound stockish, meaning the lsa has to be high to prevent shaking idle ie choppy idle. The heads...well are already going to be redone (the updated valve guides to eliminate the usage of additive) while they are off I will be doing some porting and polishing along with the machine shop decking them down for higher compression. Springs replaced with a more (modern replacement that can except a higher lift and keep the valve under control). 3 angle will also be preformed.

From the sounds of it the rocker studs will be taken care of so a replacement aftermarket rocker can be used under the STOCK VALVE COVERS.

Manifolds have to look stock, this presents a hard issue to work around...these cast manifolds are going to limit the cam we might use.

Rear gear is going to be a must! its an open rear and I am assuming a low ratio.

all this being said this is what I need suggestions for:

Cam (keep the idle smooth, remember stock manifolds)
Heads (home port and polish, decked and new studs and valve springs)
Rockers (Would like to be full roller, but under the stock gold VCs)
Gas (Premium will always be used)
Rear gear (not sure what I have now but it will need to be taller and POSI)

 

[fasttback]

I went down this path before and as time goes by you will want to change more and more parts. My recommendation (to please you dad) pull the existing stock A-code motor and save it "as is" = do no mods to it.

Get a kit motor or rebuild you own using the components you desire. When done with the motor fun, replace it with the stock motor.

 

[D.Hearne]

as long as it looks stock from the outside we are okay.

however it has to sound stockish, meaning the lsa has to be high to prevent shaking idle ie choppy idle. The heads...well are already going to be redone (the updated valve guides to eliminate the usage of additive) while they are off I will be doing some porting and polishing along with the machine shop decking them down for higher compression. Springs replaced with a more (modern replacement that can except a higher lift and keep the valve under control). 3 angle will also be preformed.

From the sounds of it the rocker studs will be taken care of so a replacement aftermarket rocker can be used under the STOCK VALVE COVERS.

Manifolds have to look stock, this presents a hard issue to work around...these cast manifolds are going to limit the cam we might use.

Rear gear is going to be a must! its an open rear and I am assuming a low ratio.

all this being said this is what I need suggestions for:

Cam (keep the idle smooth, remember stock manifolds)
Heads (home port and polish, decked and new studs and valve springs)
Rockers (Would like to be full roller, but under the stock gold VCs)
Gas (Premium will always be used)
Rear gear (not sure what I have now but it will need to be taller and POSI)

Manifolds ? You want to at least swap to the 289 Hi-po's. Cam? Something like what I listed before will be your limit (204/214 or 214/224 duration with less than .500 lift) Heads? I'd avoid decking any further than's neccessary to clean em up, you've got plenty of compression, you don't want more(especially with the cams you're limiting yourself too). Rockers under the stock lo-profile covers ? You're pretty much limited to the factory 65 rockers, which aren't bad compared to the later rail and pedestal rockers. Rear gear? go with what 68RCodeConv recommended.

 

[woodsnake]

What is the reason for the " stock appearance"?

If you are going to show it competitively, that's one thing. But if it's for looks only, pull the "A" code, and drop in something you can modify.

 

[65ShelbyClone]

What is the reason for the " stock appearance"?

If you are going to show it competitively, that's one thing. But if it's for looks only, pull the "A" code, and drop in something you can modify.

Yeah, I'm wondering the same thing. Not just appearance, but sound too? Jeez.

 

[htwheelz67]

I dont know about running an rv cam with 10-1 compression, that will really make high cyl pressure as rv cams in general use short duration and moderate to high lifts thus increasing cyl pressure, with 10-1 you will have to run premium no matter what, I did say in my post to run the xe cams you will need screw in studs and guideplates, the xe cams will work fine with 10-1 compression, wide lca's are not optimal for peak power and I wouldnt say they give the best of both worlds, the power is spread out more, less peak power, more vacuum, better idle, bigger cam wont be as radical.
I run a wide LCA 113.8 on my 408's custom cam as I wanted efi at some point and wasn't sure which type I was going to use but if I new it would always be a carbed motor I guarantee CI who did my cam would have ground it on 107-110 LCA.

The XE cams tend to idle better and pull more vacuum than similar speced cams BUT they are a bit noisy because of the fast ramps.

If you are running cast iron ex manifolds the cam will not sound as racy as it would with headers and low end torque will be increased to a point.

 

[runawayabc123]

I vote for the save the A-code engine. They are rarer and rarer as more get moded.

Just buy a used c-code (or whatever you can find) and mod that, possibly evening making it look stock.

Think of it this way, you can beat your extra mod-ed motor to snot and if you blow it up, you don't have to sweat it much as you still have the original.

 

[rbohm]

my suggestion for a cam would be to use the comp cams he260h high energy cam. it is an older design but still quite effective. you should gain about 30hp, pick up a few mpgs, and have a smooth idle. i would take the stock heads and do some port matching with the gaskets, and blend it back about 3/4-1 inch, and clean up the valve bowls. you can also install slightly larger valves in the head, a 1.94in/1.50ex is as large as you can go. i would also install screw in rocker arm studs with guide plates. this will also help you pick up power, probably about 25-30, as well as a few more mpgs. if you can find one, an old edelbrock F4B intake with a 4100 autolite carb will work real nice, but the stock 4bbl intake doesnt do too badly either. last, perhaps you can get your father to allow you to use a set of tri-y headers, they are period correct, and were sold over the counter at the ford dealership through the shelby parts program. otherwise perhaps you can invest in a set of hipo 289 exhaust manifolds. dont forget the dual exhaust.

 

[htwheelz67]

10-1 compression is way too high for a high energy cam, if you read the notes on high energy cams 9.1 or less compression, I made that mistake on a 351w once in a van and I couldn't run much timing at all which killed power and it pinged like crazy, I couldn't even run my vac advance.

 

[D.Hearne]

I vote for the save the A-code engine. They are rarer and rarer as more get moded.

Just buy a used c-code (or whatever you can find) and mod that, possibly evening making it look stock.

Think of it this way, you can beat your extra mod-ed motor to snot and if you blow it up, you don't have to sweat it much as you still have the original.

There's not that much difference between those two engine options to justify your advice. Intake, and pistons are about all that's different.

 

[htwheelz67]

The easiest route would be to get a set of larger chambered late model heads and bolt them on, that will drop you compression and then throw in the 260HE cam and some roller tipped rockers, then it will sound almost like stock and have more power AND the ability to run 87 octane.

 

[S-Car-Go]

If it were my coin, my car, and my kid, this is what I'd do..

Set the 289 aside, get a STOCK roller cammed 5.0 l motor and set it up for a carb. Swap the trans with a T5 (or AOD) and swap in some 3.25 gears.

This will:
Sound/look stock
accelerate much quicker than stock
Annihilate the skinny tires I'm guessing in the car has.
Run on 87 octane
Run down the freeway at 1700 rpms
Alleviate any conserns about new oil and flat tappet cams

You can sell it to your dad because of the great mileage it will get...

The only change I'd make is I'd put a good set of long tube headers (AccuFab, JBA or FPA) on it over the stock manifolds. Good headers (not $200 tri-y) will make a huge difference and be as reialable as manifolds.

 

[D.Hearne]

What's wrong with $200 Tri-Y's ? The ones I have on my V8 Ranger cost me $85 (ebay-used) and they've been the best $85 headers I've ever had.

 

[S-Car-Go]

I've had heddman, hookers, numerous cheap tri-ys on different cars over the years. Can't tell you how many gaskets I've replaced. I've always just considered it part of having headders. Soaked them, retorqued them, yada yada. Scrape the lower flange and develop a leak. Part of life, at least for me.

I bought this car about 4 years ago. I bought some headers I never would have bought in the past. Fit and finish are better than I expected. I will never scrape them since they don't hang under my frame. There is a ball and socket down low, so there is no gasket to blow out. I've had then on and off several times and used the same head/flange gasket. I've never had a leak. They seem quieter in the engine compartment, but I can't validate that. They are heavier gauge steel though.

If your cheapies work for you, cool. I never thought I'd like the pricey ones as much as I do.

 

[D.Hearne]

Use cheap header gaskets and you DO get the negative results you experienced. The gaskets under my cheap tri-y's are Percy's. Nary a leak since they've been used. Been reused at least 4 times now too. On two different heads. None of the Shelby type tri-y's I've seen hang lower than the frame either. Had Hookers on my big block Stang twenty years ago. Those did hang down, got banged up and leaked constantly with the asbestos gaskets. (didn't have the gasket choices available today then)

 

[65ShelbyClone]

The only header gaskets I have had blow out from being low quality are the fiber ones with no metal backing. I have blown out the metal-backed ones when a bunch of header bolts rattled loose, but that is to be expected. Incidentally, Hooker Comps seem to be the only header I have used that doesn't need the bolts to be checked constantly.