440HP build plans. Suggestions? What do you run?

68Satellite440

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Hey guys,
I’ve got a ‘68 440HP stock motor. Built Jan 22 by 2nd shift. Im planning to swap Cams and maybe some head work if i can find a shop near southern Oklahoma.
I dont know which Heads were used in 1968. Motor runs great, no issues, only add ons to my knowledge was new ignition and headers.
To be totally honest I don’t understand Cam durations yet but I’m wanting a Cam with plenty of lope and staying under 6k RPMs. I dont wanna push my luck too far and damage the motor, just want a aggressive responsive street car to make some of these GT Mustang owners wanna go sell them.
I have a 727 transmission, Edelbrock Performer 600cfm, currently have 2.76 gears from the original 318, planning on 3.55 sure-grip swap. Running 295/50r15 tires.

Any suggestions or recommended changes?

768C8CD7-656F-4352-AD6F-8AFC01CDC635.png
 

Jerry Hall

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68 HP stock engines used 906 heads in both 383's & 440's. If you have a good running motor, I suggest you turn your attention to the rear end. Get your 3.55 gears and make sure that 727 is up to snuff. Then run a compression check to all cylinders to verify the health of your engine. I would also suggest a refresh of your engine with any cam changes. Upping the HP and performance of an engine with wear is asking for trouble as you have already stated that you want the Mustang owners out of your hair. It would be more embarrassing to me to hurt an engine in the process. Don't give them those bragging rights. Do it right the first time, you won't regret it. Cam choices are abundant, but the rest of your choices have to be considered in the equation. Building performance is more than just replacing a cam.
 

Cheapsunglasses

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I would also suggest you go with a 750-800 cfm carb. 600 might be too small.

I would suggest a factory avs. Or an edelbrock. Edelbrocks are really easy to tune, a good carb for street duty
 

R413

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Dump the 600 carb you have. I like an 800 AVS II

If you want to beat a stock Mustang GT from the 80’s or 90’s no problem, but the. Late models you may have some trouble.
 

Geoff 2

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Concur,
Edel 800 AVS2. The '2' version has annular pri boosters for superb throttle response.
I don't think staying under 6k & blowing off GT Mustangs are mutually compatible.
Cams? Hyd, solid? Roller, FT?
For a Hyd FT, I would suggest the comp Cams XE284. Cams become a diminishing return...
They shift the power band. If you go too big, you lose a lot of low end. Ya gotta get to 3k before ya get to 6k...It s a compromise.
 

68Satellite440

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68 HP stock engines used 906 heads in both 383's & 440's. If you have a good running motor, I suggest you turn your attention to the rear end. Get your 3.55 gears and make sure that 727 is up to snuff. Then run a compression check to all cylinders to verify the health of your engine. I would also suggest a refresh of your engine with any cam changes. Upping the HP and performance of an engine with wear is asking for trouble as you have already stated that you want the Mustang owners out of your hair. It would be more embarrassing to me to hurt an engine in the process. Don't give them those bragging rights. Do it right the first time, you won't regret it. Cam choices are abundant, but the rest of your choices have to be considered in the equation. Building performance is more than just replacing a cam.
Going through the motor is certainly on the list. I have suspension upgrades to do first, all new bushings, new leafs, bilsteins, etc. You saw my other posts, i have my share of body work to clean up as well but being mechanically sound is my main priority. Being able to drive the hell out of this car with 100 percent confidence.
The point of this post was i like to have my game plan and research done way ahead of time so i dont waste a bunch of time later, i just execute the plan as directed by the gearheads with the knowledge and learn everything i can along the way. I appreciate your input!
 

68Satellite440

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Dump the 600 carb you have. I like an 800 AVS II

If you want to beat a stock Mustang GT from the 80’s or 90’s no problem, but the. Late models you may have some trouble.
The 600 will definitely go, the car was previously used to do “Cruisin the Coast” down in Mississippi where i bought it. They wanted it gas efficient as possible so im assuming thats why they didn’t go 750 or bigger and left the 2.76 gears.
As far as the mustangs go, ive gave several around here a scare with my single cab 5.7 truck with 3.92s. They pulled away from me when i governed out. I have full confidence this big block can produce more hp and tq than my stock 5.7 hemi. I think its just gonna come down to fine tuning and getting my gearing correct. Do you think the Cam and head work isnt necessary? Just bigger carb, timing adjustment, and gear change?
 

68Satellite440

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Concur,
Edel 800 AVS2. The '2' version has annular pri boosters for superb throttle response.
I don't think staying under 6k & blowing off GT Mustangs are mutually compatible.
Cams? Hyd, solid? Roller, FT?
For a Hyd FT, I would suggest the comp Cams XE284. Cams become a diminishing return...
They shift the power band. If you go too big, you lose a lot of low end. Ya gotta get to 3k before ya get to 6k...It s a compromise.
Well I’m all ears, im only posting what recommendations i know of. If your in my boots with my goals, whats your plan of attack to hurt these boy’s feelings? What else would you do to a stock hp motor?
 

66Satellite47

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The 600 carb is a little small, small carbs can work too. I'm a Holley guy, never got the hang of most Carter/EDE style carbs. A 750-800 CFM is the common range for 440. You are spot on with the intent to stay below 6000 RPM. High RPM kills parts, I know.
Cam selection is amazingly complicated. But my main experience has been for my drag cars. The motor I built for tow van, I used the old Comp High Energy 260. It did great in the 360, good gas mileage, good power. Lots of choices out there. Don't choose based on "lope".
 

493 Mike

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Get your combination settled then call Hughes for a cam recommendation. They specialize in Mopar.
Mike
 

Challenger340

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I would also suggest you go with a 750-800 cfm carb. 600 might be too small.

I would suggest a factory avs. Or an edelbrock. Edelbrocks are really easy to tune, a good carb for street duty
where is the 440 HP Engines original Carb ?????????????????????
Because if it's a '68 "HP" 440 Engine ?
they were already equipped from the factory with a larger Carter AVS Carb, which is already up around 730 cfm ?
why would someone remove a High cfm Flow Carb and install a smaller 600 ?

They were advertised back in the day at 800 cfm I think ?
but when I Flowed my 1969 440 Magnum's Carter AVS Carb here(Carter 4618S) it came in around 730'ish cfm as tested.

If the OP's 440 Engine is a true 1968 440 Magnum ?
then it should already have the same 1968 version either the Carter 4428 or 4429 Carter AVS Carb with the higher CFM Flow.
 
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Cheapsunglasses

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If it's a '68 "HP" 440 Engine they were equipped from factory with a larger Carter AVS Carb, which is already up around 730 cfm ?
They were advertised at 800 cfm I think ?
but when I Flowed my 1969 440 Magnum's Carter AVS Carb here(Carter 4618S) it came in around 730'ish cfm as tested.

If the OP's 440 Engine is a true 1968 440 Magnum ?
then it should already have the same 1968 version either the Carter 4428 or 4429 Carter AVS Carb with the higher CFM Flow.
Carter 4640 if I’m not mistaken
 

Challenger340

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WileERobby

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Assuming bottom-end is up to snuff. Heads ? $$$ ? mild re-work, or go to aluminum it's up to your pocketbook. Call hughes with you combo for a good cam. Holley Street dominator with a 440 Thermoquad carb. Your gear swap is an absolute must. And, I'm going to say you're probably going to need new springs.
 

Cheapsunglasses

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But since this isn’t a stock engine, and the cam is changing, I second the edelbrock avs2 800 cfm, with tuning kit
:thumbsup:
 

Challenger340

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For factory HP Exhaust Manifolds and the factory 4 holer '2178' 68/69 Intake/800 AVS
Crower HDP271....
or the SUMMIT K6400 works pretty darn fine as well !
You could even get the Comp XE268H ground on 114 lsa and Nitrided ?

Headers:
you can use the stock CompCams XE268H on the offered 110 lsa
 

68Satellite440

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where is the 440 HP Engines original Carb ?????????????????????
Because if it's a '68 "HP" 440 Engine ?
they were already equipped from the factory with a larger Carter AVS Carb, which is already up around 730 cfm ?
why would someone remove a High cfm Flow Carb and install a smaller 600 ?

They were advertised back in the day at 800 cfm I think ?
but when I Flowed my 1969 440 Magnum's Carter AVS Carb here(Carter 4618S) it came in around 730'ish cfm as tested.

If the OP's 440 Engine is a true 1968 440 Magnum ?
then it should already have the same 1968 version either the Carter 4428 or 4429 Carter AVS Carb with the higher CFM Flow.
The original carb was removed long before my owning it. There was a old holley on it previously that i havent found the model number. All rusted up. The guy i bought it from just liked to cruise around and cared nothing about performance, so he had his mechanic put this Edelbrock Performer on it. I was surprised the car even ran decent with only a 600cfm.
 

slepr1

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I also agree on getting a Hughes cam. I finally did and its the best cam I've had. I wish I would've saved my money on all the work I had done on the old iron heads I use to have. For cheaper I finally got a set of Edelbrock aluminum heads and they were better.

If you wanna race mustangs (and eventually any muscle car) you'll def need to upgrade/replace almost everything from the front to the back. Our cars were engineered for 350-400hp. You'll need 450-500+hp to beat the lighter muscle on the road imo. I started out wanting the same thing. As I increased the hp/torque of my 440 more things started to show their age. Things like u-joints, overheating, gears all needed attention. What you skimp on now you'll regret later. Welcome to the club!
 

Cheapsunglasses

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The original carb was removed long before my owning it. There was a old holley on it previously that i havent found the model number. All rusted up. The guy i bought it from just liked to cruise around and cared nothing about performance, so he had his mechanic put this Edelbrock Performer on it. I was surprised the car even ran decent with only a 600cfm.
I ran a 625cfm 383 avs on my 440 until I could find a 440 carb. You couldn’t jab the throttle, and you couldn’t go full throttle, or it would be way too lean. Once I found a 750 cfm 440 afb, just changing the carb really woke up the car. That’s why I suggested carb before anything else. Also put an air to fuel ratio gauge so you can see what’s going on.
:thumbsup:

I know you’ll get a lot of different opinions on carbs. The Thermoquad is a good carb, a lot of people don’t see the full potential, and you can get them pretty cheap.

Or if you can afford it and hit the easy button. The Edelbrock avs2 800cfm is a good choice too. Buy the tuning kit that comes with it, it’ll have a chart to help based on your afr numbers, most of the time it’s just metering rod changes, and you don’t even have to take the entire carb apart to do that. Just loosen these screws, pull the cover to the side, and make your change.

7931ABC2-ABAE-4DBD-886B-25628C926C8E.jpeg
 

68Satellite440

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68 HP stock engines used 906 heads in both 383's & 440's. If you have a good running motor, I suggest you turn your attention to the rear end. Get your 3.55 gears and make sure that 727 is up to snuff. Then run a compression check to all cylinders to verify the health of your engine. I would also suggest a refresh of your engine with any cam changes. Upping the HP and performance of an engine with wear is asking for trouble as you have already stated that you want the Mustang owners out of your hair. It would be more embarrassing to me to hurt an engine in the process. Don't give them those bragging rights. Do it right the first time, you won't regret it. Cam choices are abundant, but the rest of your choices have to be considered in the equation. Building performance is more than just replacing a cam.
Do you happen to know what size torque converter came from factory in these? To my knowledge its never been changed.
 
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