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Discussion Starter #1
1966 289, C4, 2.80 rear end. The engine is a stock '66 block. Seven bores are within .003 of new, but one is worn about .006 or so with .004 taper. I don't think a simple hone & re-ring is a good idea, but feel free to disagree if you want (it would save me close to $500 in machine work and pistons). If I have to pay the $300 or so to bore & hone, I'll just go .030 over.

Flat top pistons (or? The originals are slightly dished...)
Either stock GT40P heads - close to 9:1 or 9.5:1 compression
Stock cast iron exhaust manifolds
Either stock 4V or maybe something like an Edelbrock Performer street intake (not selected yet)
4V carb (likely a 4100), not selected yet

I could re-use the original heads, but I have read that the GT40P heads would breathe better. It would probably be as expensive to use the old heads as to replace them, since the tops of the valves are grooved and worn from the rockers.
Not looking to spend a fortune on machining them.

Nothing wild. Not a race car. With those gears I'm looking for good low and midrange torque. It doesn't need a silky smooth idle, I want it to sound good but not lope and spew half-burned gas. There are thousands of cams out there, and I'm not an expert. What say ye, assembled experts?
 

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Discussion Starter #3
Yeah... I saw that, and I'm guessing that cam would probably not be a good choice for me, considering it's a completely different engine, different gears, exhaust, heads, and different requirements.
 

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lol Right you are, Dale. =) With GT40P heads, even a mild cam will do really really well. A nice wide LSA to ensure your car pulls right from off-idle to whatever its peak winds up at. Summit M-series carb with a Weiand Stealth, and you'd have a lot of fun. Make sure your spring rates match whatever you're going to do. The stock springs on GT40P's are soft by roller-cam standards, but not sure they'd be right for a low-rpm flat-tappet cam, and wiping your lobes to find out would not be the recommended method.
 

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Discussion Starter #6
Keep in mind the gt40p heads will require special headers.
Now that you mention it... I wonder if the stock cast iron exhaust manifolds would work or not. Yeah, I know, they suck... but a set of headers is really not in the budget, since it would also require tossing or at least heavily modifying the perfectly good, near new exhaust system that's' already there. If those wouldn't bolt up to the GT40P heads, then I'd probably stick with the stock heads. (echo) Yeah, I know, they suck... :) But again, street car, mild build, not building a stoplight terror.
 

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Spammer Hammer
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The Comp Cams N271 is a decent cam for the street. Its somewhat comparable to the original HiPo cam, but with a much tighter modern lash and some other minor tweaks. I ran the N271-S (solid lifter) for about two years. Drove it to and from the NPD show in Ocala and averaged 16 MPG. Ill add, cam choice should definitely be based on the entire engine build. You will get at least 100 different opinions. Talk to Comp or whomever you prefer and describe the entire engine and the exact use of the car. They will point you in the right direction.

At the very least, you should consider some repo Scott Drake HiPo exhaust manifolds. Otherwise, anything you do to the engine will be wasted right at the exhaust port interface.
 

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HiPo manifolds will work with GT40P heads. I'd recommend those and a stock 5.0 HO roller cam with linkbar lifters or an E-Cam. Keep it simple.

As for the intake manifold, I like the Weiand Street Warrior for lightly modified 289s. A Summit 500cfm carb is a decent alternative to the 4100.

All of the above should give you a really nice, reliable engine with good street manors and a decent amount of power.
 

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Go with a .020" overbore.
Pistons: Silv-O-Lite Hypereutectic 3101HC-020
Intake: Weiand Stealth #8020
Carb: Summit M2008VS500
Lifters: Trick Flow TFS-21400006
Cam: M-6250-B303
Exhaust Manifold: Reproduction HiPo
 

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For a lot less money and trouble buy a good used GT40P! That’s what I did. Paid $450 for one with the trans. Sold off what I didn’t want for $175. Net cost was $275. Bought a used 5.0 cam $60, used Wieand Stealth $80, used Edelbrock 600. $125. Put a spring kit in. So not a lot of money invested. Not built to Grimbrand’s suggestions just happened to. Let me tell you, it runs real well! I almost hate to change anything because it runs so well and it was stupid cheap
 

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If you're going to stay with a stock torque converter and 2.80 gears, be extra careful with the cam choice. I've built a similar SBF (Performer intake, small Holley, Hi-Po Exhaust Manifolds, stock H-Pipe duals) a few years ago, and went with a 204 / 214 / .449" / .473" 112/ LC cam, advanced two additional degrees. It was peppy and responsive, but I wouldn’t call it powerful. It was done by about 4,500 rpm.
 

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I am with bbmach. I ran the Performer .448/.472 cam and it worked well with an auto and 3.00 gears. Run headers if you can.
 
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I ran a Jegs brand 448/472 in my old 289. It ran really well I do wish I had used new valve springs when I did it though
 
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