273 mild build cam

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xLURKxDOGx

xLURKxDOGx

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I ordered this comp cams CCA-20-304-4 for my new 273 build but started to notice this looks like a mild cam for a 360. Is this overkill and going to barely idle? This build is going to be my driver but I wanted to get close to HP 273.

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That cam should be fine. 4 degrees less intake and 2 degrees more exhaust at .050 than an Isky E-4, which is a great 273 solid cam for the street. I've run 340 cams in 273's and they worked good, you should be where you want to go with that cam. Commando 273's were rated 235 hp. Why did you go hydraulic?
 
Should be a good cam for you. If you're changing from the stock solid cam to a hydraulic you will need different lifters (of course) and shorter pushrods. tmm
 
I'm kind of in the same boat with my 273 build. I have a 67 Barracuda Convertible with a 4 speed that I rebuilt in 1995, basically stock using the Comp HE-252-H and it is VERY stock. I'm in the process of pulling the engine for a performance gain but since I use this car in parades I don't want some crazy lopey cam that will not idle and puffs fumes of unburnt fuel into the marching band behind me.

I have read through Tool Man Mike's build thread probably ten times and wanted to do some of the same performance upgrades, but I'm afraid I might wind up with a killer street machine like Mike has which is not suitable for parades and my wife driving it from time to time. I really like the Isky E-4 cam because I want to stay with the solid lifters but it's just a little too wild for what I want to do.

If there was a way to tame the E-4, get it to idle well and still have all the benefits of a great cam, I'd go that route but for my purposes I believe it to be a little too much. If I had more cubes, could run 340 heads (without notching my block) or a higher compression I could probably use the E-4 but I need to find a compromise in between what I'm running now and the E-4.

I have read on this forum the quality of Comp Cams has slipped since I did my first build in 1995, but will probably have to stick with them because they can offer me a solid grind in almost any cam I select.
 
There's been no slip in Comp's quality. None that's affected me and I've been using them in all kinds of stuff since the 80s up to this past summer.
 
I looked up specs on Isky E4, has a smooth idle, 216 deg @.050, .425 lift, strong torque.
I used one in my 273 long time ago, sounded just like a stock cam. its not a big cam!
 
66fs said:
That cam should be fine. 4 degrees less intake and 2 degrees more exhaust at .050 than an Isky E-4, which is a great 273 solid cam for the street. I've run 340 cams in 273's and they worked good, you should be where you want to go with that cam. Commando 273's were rated 235 hp. Why did you go hydraulic?
Click to expand...

I went with hydraulic because that is what was in there when i tore it down and figured thats how it came. It was until later after i had ordered it that i saw a bunch of articles about how people dont recommend using them. Is there that much of a difference power wise?

toolmanmike said:
Should be a good cam for you. If you're changing from the stock solid cam to a hydraulic you will need different lifters (of course) and shorter pushrods. tmm
Click to expand...

I found a set of adjustable ones at the junkyard and ordered a set of comp 7 3/8(original were about 1/8 bigger) which i figure should be ok since its not a huge lift cam. How different is it from your ISKY and how does that idle for you?


Thanks for the rest of the input guys!!

Jake
 
mopardude62 said:
I'm kind of in the same boat with my 273 build. I have a 67 Barracuda Convertible with a 4 speed that I rebuilt in 1995, basically stock using the Comp HE-252-H and it is VERY stock. I'm in the process of pulling the engine for a performance gain but since I use this car in parades I don't want some crazy lopey cam that will not idle and puffs fumes of unburnt fuel into the marching band behind me.

I have read through Tool Man Mike's build thread probably ten times and wanted to do some of the same performance upgrades, but I'm afraid I might wind up with a killer street machine like Mike has which is not suitable for parades and my wife driving it from time to time. I really like the Isky E-4 cam because I want to stay with the solid lifters but it's just a little too wild for what I want to do.

If there was a way to tame the E-4, get it to idle well and still have all the benefits of a great cam, I'd go that route but for my purposes I believe it to be a little too much. If I had more cubes, could run 340 heads (without notching my block) or a higher compression I could probably use the E-4 but I need to find a compromise in between what I'm running now and the E-4.

I have read on this forum the quality of Comp Cams has slipped since I did my first build in 1995, but will probably have to stick with them because they can offer me a solid grind in almost any cam I select.
Click to expand...


As said in the last post or two the E-4 is a mild cam. Just barely a lope. I wish mine was more aggressive. I have a couple U tube videos of the sound if I can find them. tmm
 
A lot of issues with idle quality have to do with tuning. What is the timing like in your car? I'd think that E4 would be fairly mild to stock sounding...
 
[ame="https://www.youtube.com/watch?v=ARQ9WrSP0xk"]008 2 - YouTube[/ame]
 
Toolman thanks for the post of your car running with the E-4. It sounds nice so I think that's the way I'm gonna go. Several members here agree with you and says it's a great mild cam. In your video it sounds great, so I'm going to run with it. Thanks to all who posted.
 
xLURKxDOGx said:
I went with hydraulic because that is what was in there when i tore it down and figured thats how it came. It was until later after i had ordered it that i saw a bunch of articles about how people dont recommend using them. Is there that much of a difference power wise?



I found a set of adjustable ones at the junkyard and ordered a set of comp 7 3/8(original were about 1/8 bigger) which i figure should be ok since its not a huge lift cam. How different is it from your ISKY and how does that idle for you?


Thanks for the rest of the input guys!!

Jake
Click to expand...

I prefer solid cams but for a HP 273 I think it would work fine for a daily driver. Stock Commando cams were pretty small.
 
The solid cam is the way to go for a 273 and the E-4 is a perfect Commando motor replacement. You will probably need modified pushrods for use with the hydraulic lifters but I think you are going to like your selection.
 
I went with a Comp Cam 20-246-4 on my 273 rebuild

The goal was a pretty mild engine build that did not have to many modifications

Car runs solid, no over heating or idling issues. And it does have nice sound and some get up
 
Here is some information I gathered for my build. Of course reading toolmanmike and other resources

273 Commando – (rated at 235 Horsepower)
CAM Valve lift: Intake .425 and Exhaust .425
CAM Duration: Intake 248 and Exhaust 248

273 Standard – (rated at 180 Horsepower)
CAM Valve lift: Intake .395 and exhaust .395
CAM Duration Intake 240 and exhaust 240

Comp Cam 20-246-4 (what I used)
Valve lift intake .468 and exhaust .468
Duration intake 270 and exhaust 270

Here is Comp recommended for my build
Comp Cam 20-222-3
Valve lift intake .462 and exhaust .470
Duration intake 262 and exhaust 270

Isky E4 cam
Valve lift intake .425 and exhaust .425
Duration intake 260 and exhaust 250

And how can we talk 273 without a reference to the D-Dart

D-Dart
Cam Valve lift intake intake .495 exhaust .505
CAM Duration: Intake 284 and Exhaust 284
 
cam/valve movement lies between fuel air mixture in and air flow out. Intake and carb choice along with exhaust configuration will have as much or more bearing on tuning, idle, richness, etc..
 
I have been looking for the correct dimensions for hydraulic pushrods when using adjustable rockers. So far I found a post that mentioned 5/16" ball/cup pushrods that are 7.342" long. Anyone else have any other recommendations? I'll keep looking. We need a sticky on this.
tmm
 
I think there are too many variables.
Which heads and how much milling is done or has been done before, adjustable or non adjustable rockers, stock or aftermarket. That's why there isn't a set length called out repeatedly. To measure what length is needed for each build is the best plan.
 
RedFish said:
I think there are too many variables.
Which heads and how much milling is done or has been done before, adjustable or non adjustable rockers, stock or aftermarket. That's why there isn't a set length called out repeatedly. To measure what length is needed for each build is the best plan.
Click to expand...

Good point. Stock heads with no more than a clean up pass on the mill and the stock length pushrods should work with a hydraulic cam. A mock-up is the best thing to do.
 
66fs said:
Why did you go hydraulic?
Click to expand...

moper said:
A lot of issues with idle quality have to do with tuning. What is the timing like in your car? I'd think that E4 would be fairly mild to stock sounding...
Click to expand...

The issue with some of the info provided is that advertised duration means nothing. Compare duration at .050 and if possible compare the .050 to .020 specs. LSA also isn't mentioned and make s a huge difference in the way they idle.

For instance advertised 284 and at .050 206, etc..

The cam you typed in the first post is 212/218 duration @ .050. 444 lift. 110LSA


Check out these cams. This is in the realm of what you are looking at. The Howards for example claims "mild idle, good low RPM power"

Crane 699611 // 214 int./222 exh @ .050. 0.488 int./0.509 exh. 112LSA

Crower 31240 // 214 int./218 exh @ .050. 0.455 int./0.474 exh. 112LSA

Howards 711651-10 // 218 int./226 exh @ .050. 0.502 int./0.525 exh lift, 110LSA
 
roccodart440 said:
The issue with some of the info provided is that advertised duration means nothing. Compare duration at .050 and if possible compare the .050 to .020 specs. LSA also isn't mentioned and make s a huge difference in the way they idle.

For instance advertised 284 and at .050 206, etc..

The cam you typed in the first post is 212/218 duration @ .050. 444 lift. 110LSA


Check out these cams. This is in the realm of what you are looking at. The Howards for example claims "mild idle, good low RPM power"

Crane 699611 // 214 int./222 exh @ .050. 0.488 int./0.509 exh. 112LSA

Crower 31240 // 214 int./218 exh @ .050. 0.455 int./0.474 exh. 112LSA

Howards 711651-10 // 218 int./226 exh @ .050. 0.502 int./0.525 exh lift, 110LSA
Click to expand...

Ouch, I would like to hear either of those in a 273 for a guy wants a smooth idle. The Crane is a hydraulic roller so it's out of the question. The operating range of the last two start turning on at 1800 rpm and with lift approaching and exceeding .500 they aren't very mild cams. The original poster was concerned that the Comp he picked out might be too radical and it was a 212/218-.444-110°
 
toolmanmike said:
roccodart440 said:
The issue with some of the info provided is that advertised duration means nothing. Compare duration at .050 and if possible compare the .050 to .020 specs. LSA also isn't mentioned and make s a huge difference in the way they idle.

For instance advertised 284 and at .050 206, etc..

The cam you typed in the first post is 212/218 duration @ .050. 444 lift. 110LSA


Check out these cams. This is in the realm of what you are looking at. The Howards for example claims "mild idle, good low RPM power"

Crane 699611 // 214 int./222 exh @ .050. 0.488 int./0.509 exh. 112LSA

Crower 31240 // 214 int./218 exh @ .050. 0.455 int./0.474 exh. 112LSA

Howards 711651-10 // 218 int./226 exh @ .050. 0.502 int./0.525 exh lift, 110LSA
Click to expand...

Ouch, I would like to hear either of those in a 273 for a guy wants a smooth idle. The Crane is a hydraulic roller so it's out of the question. The operating range of the last two start turning on at 1800 rpm and with lift approaching and exceeding .500 they aren't very mild cams. The original poster was concerned that the Comp he picked out might be too radical and it was a 212/218-.444-110°
Click to expand...


Thanks everybody for the insight, especially that link to the 273 article, fantastic stuff! Who would have thought 300 was as easy to get to, not to mention pricey and after reading more about hydraulic vs solid lifters/cam the only advantages I read were after 5200 rpm and I'm not sure I'll get there so it looks like I'll stick with the lifters, now the only question is how big can you go on stock converters rear gears?

Jake

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I'm not sure if this car has the correct D/Dart cam in it or not. But I plan on finding out for my records. It does sound healthy.


[ame="https://www.youtube.com/watch?v=Fo9Jzk7g8is"]Start Up - 1966 Dodge D-Dart Lightweight Trans Am Race Car - YouTube[/ame]
 
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