440 Cam Suggestions

[BSB67]

Yes, you've nailed it exactly! Thanks --------------- Mark.

You've mentioned several times money is tight. And its not clear if the budget rebuild is still in the cards along with the cam or not.

What is your budget?

 

[69 Charger Mark]

You've mentioned several times money is tight. And its not clear if the budget rebuild is still in the cards along with the cam or not.

What is your budget?

Hey BSB67, I keep mentioning budget because I need to stick with my stock heads and rocker arm assembly. Some of the post have mentioned going with new heads. The refresh / rebuild will be done regardless while the engine is out. cam, lifters, timing gear, turn the crank, hone the cylinders and hope we don't have to bore it, rings, reuse same pistons and rods if they are ok. That I have a budget for. I don't have the budget for new heads and roller cam and lifters. As I mentioned before it's getting ready for paint. Basically we are replacing the whole rear clip with AMD and the engine has to come out to paint the engine bay. What i would like to do is go with the trickflow upper end kit and let the machine shop that does most of the engines in my mopar club handle the rebuild and dyno. Trickflow upper end kit is around $4K and machine shop / dyno day is another $6K. That will happen a couple of years in the future but not right now. Thanks for the post. I appreciate everyone's help. I'm trying to make sure I get it right so i don't have to spend another $500 for another cam kit and then have to pull the engine back out of the car. Thanks again.

 

[451Mopar]

Powerwise, Anything you do to make the heads flow better will make a much larger difference in power than which cam you choose.
The main difference between the two cams is intake/exhaust overlap. This will change how the cams sound at idle. The smaller cam will be smoother, and the larger cam a bit more chopy at idle. The smaller cam will have more vacuum at idle. Alot depends on how you plan to use the car.
For daily driving, and lugging the car around at low RPMs the smaller cam is the one to use. For spirited driving and racing, the larger cam is better.
If racing or running through the gears, the smaller cam may help through the first 1/2 of first gear (if you leave at 1,000 RPM). The larger cam will have more power through the second 1/2 of first gear, and all of second, third, and forth gear. And usually, you will launch the car at a higher RPM anyway.

When your driving normally, just crusing, your not at WOT anyway, so the main difference with the smaller cam is you can lug the engine a bit more, get into a higher gear at a lower RPM, and the smother, higher vacuum, at idle.

 

[69 Charger Mark]

There is too much advertising BS in the cam catalogs. All the choices are a compromise. It really comes down to preference.
The smaller cam will be slightly better below 3,000 RPM, If you have a 2.66:1 first gear, 3.55:1 rear gear and 27" tall tires, so below 25 MPH (in first gear), and if most of your driving is below 3,000 RPM (70 MPH in 4th gear) use the smaller cam.
The Engine simulator makes look like the smaller cam gives about 4 more HP (about 14 ft/lbs of torque @ 1,500 RPM) from idle to 2500 RPM.
The larger cam has more power and torque above 3,000 RPM, but it does not look like a drastic amount, about an extra 15 Hp @ 5,000 RPM.
This is assuming the heads are stock, unported. The stock heads are the limiting factor, much more than the compression.
The smaller cam would be easier to tune because it has much less overlap (smoother idle.)

451Mopar excellent feedback. Since most of my driving will be general cruising with the occasional street light to street light encounter. Do you think the 702 would be the better choice or do you think there would be only a slight difference between the two. Appreciate the feedback / advice.

 

[69 Charger Mark]

The 702 has a wider 112 lsa and less duration then a 703... but both the 702 and 703 have the very similiar power bands because they open the exhaust and close the intake valve within a few degrees of each other. The 703 duration increase mainly shows up in the overlap. The extra overlap is helpful to make more power with the scavenging done with headers. I wouldn't want to give up the top end hp of 703 to gain it on the bottom unless I was towing. LOL

Hey Curiousyellow71, definitely wont be towing but might be doing some hauling. LOL! I'll pose the same question to you as I did to 451Mopar. Considering my use will be general cruising with the occasional street encounter would the 702 be the better choice than the 703. It will make one trip the strip for a little grudge race against one of my best friends SSR. The trash talking has already begun. A picture of Franklin and a case of adult beverages from Tennessee to the winner.

 

[451Mopar]

The smaller 702 is a good choice, and if you car was an automatic with a stock converter, Then I would for sure use the 702. The 4-speed allows the 703 to work if your looking for more performance, otherwise the 702 will be easier to live with for normal driving.
The 702 will make the tuning much easier because the carb will have a better signal (more vacuum with less pulsations.)
Also, because it is slightly less lift, it should be slightly easier on the valve train (lower open spring pressures, not sure how opening ramp rates compare?)

If you have to bore the block, then your getting into a totally different animal, because then your replacing pistons, and basically getting into a total rebuild of the short block, and then you would want to make considerations for your ultimate goal with the Trick Flow heads, unless you plan to build/rebuild again for those changes.

 

[Curiousyellow71]

I 2 like the 703 better w the headers and 4 speed. The only time you will notice the extra torque the 702 gives is below 3k in first gear...and that will likely be tire smoke unless your running slick's at the track. I wouldn't get tired of listening to the 703...but I find the 702 a little boring...but that just me.(we have a 704)..The 703 has a modest lope to it. It's not a mopar in the video..and a 440 will lope less then a 400

And the 702 but in a engine closer size to a 440

 

[69 Charger Mark]

The smaller 702 is a good choice, and if you car was an automatic with a stock converter, Then I would for sure use the 702. The 4-speed allows the 703 to work if your looking for more performance, otherwise the 702 will be easier to live with for normal driving.
The 702 will make the tuning much easier because the carb will have a better signal (more vacuum with less pulsations.)
Also, because it is slightly less lift, it should be slightly easier on the valve train (lower open spring pressures, not sure how opening ramp rates compare?)

If you have to bore the block, then your getting into a totally different animal, because then your replacing pistons, and basically getting into a total rebuild of the short block, and then you would want to make considerations for your ultimate goal with the Trick Flow heads, unless you plan to build/rebuild again for those changes.

Oh let's hope we don't have to bore the block. You're right. That would be a different animal that could result in a additional wave of spending and possible divorce LOL! Since it isn't a daily driver and I'm wanting to have some fun I think I'm going to settle on the 703 save my nickles and dimes and then do my trickflow engine rebuild in a couple of years. I also have interior to do as well. Ka-Ching! One step at a time, one project at a time.

 

[69 Charger Mark]

I 2 like the 703 better w the headers and 4 speed. The only time you will notice the extra torque the 702 gives is below 3k in first gear...and that will likely be tire smoke unless your running slick's at the track. I wouldn't get tired of listening to the 703...but I find the 702 a little boring...but that just me.(we have a 704)..The 703 has a modest lope to it. It's not a mopar in the video..and a 440 will lope less then a 400

And the 702 but in a engine closer size to a 440

703 it is. Thanks!