Could my mileage get any worse with a bigger cam?

[Paul G]

I would like to switch to a lumpier cam. I have been putting it off for any number of reasons. But, if all goes well I think it could happen this summer. The cam in there now is a Comp 21-221-4, duration at .050 212/218, 110 separation. It's in my 440 bored .030 over, 9.5:1 pistons, ported stock heads, RPM air gap intake, Holley 750, 2000 stall, 3.55 gears.

First question; Is this a pretty mild cam? It sure feels like it.

Second: I am getting about 7.5 mpg with the car. Would a lumpier cam actually make that worse? (if it can get worse)

Third: Might as well ask about cams right now. I know Chryco likes the Engle cams. Which one would go best with my setup?

Since I put those beefy tires on the rear last year the engine is having a hard time lighting them up. It used to be pretty easy to light up the old tires. I need more power I guess.

One more thing, the engine was rebuilt in 2000 by Zimmerman Racing in Phoenix if anyone has ever heard of them. It has maybe 20,000 miles on it since rebuild.

[firefighter3931]

Paul, that is a mild cam...it probably doesn't have much lift. There is power to be had with a cam swap....for sure. With your converter i would go with an engle k56 on a 110* lsa installed on a 106* intake centerline. Fuel consumption can depend on the engine's state of tune....timing plays a big role along with jetting.


Ron

[Chryco Psycho]

I agree , with the intake & converter a K56 is a nice fit or a K56 intake & K58 exhaust split profile with a 110* lsa

[aifilaw]

all suggestions aside...the combo you listed should be getting 10mpg+ with an amateur tune...I'd say its way off

[Paul G]

I called Engle this morning. He also suggested the K56 cam with a new set of lifters. He sells Chrylser high performance lifters. Should I get those from him or is there a better choice in lifters?
Like these maybe
http://store.summitracing.com/partdetail.asp?part=CRN%2D99378%2D16&autoview=sku

or these
http://store.summitracing.com/partdetail.asp?part=LUN%2D71977&autoview=sku

or these
http://store.summitracing.com/partdetail.asp?part=CCA%2D882%2D16&autoview=sku


Will I have enough vacuum for the power brakes with the K56?

[GreenMachine]

  I have a combo similar to that except with 3.23 and a Carter with Edelbrock heads. Mine gets about 11 hwy and 8-9 city and will run the 1/4  in 13.3. I chose the Carter because they generally get better mpg than Holley. I chose the cam before I knew what I was doing (should've went a little bigger), I'm just waiting for the lower zinc content oil I'm using to wipe it out so I'll have an excuse to replace it.
   I would listen to firefighter, the timing has a big effect on fuel consumption. He also recommended a cam for another car of mine that I was extremely happy with. Thanks Firefighter.

[firefighter3931]

Paul, the k56 will make lots of vacuum for your power brakes....no worries there. For lifters go with what engle recommends for their cam. I do like those Lunati lifters with the heavy duty snap ring. 



Ron

[firefighter3931]

  I have a combo similar to that except with 3.23 and a Carter with Edelbrock heads. Mine gets about 11 hwy and 8-9 city and will run the 1/4  in 13.3. I chose the Carter because they generally get better mpg than Holley. I chose the cam before I knew what I was doing (should've went a little bigger), I'm just waiting for the lower zinc content oil I'm using to wipe it out so I'll have an excuse to replace it.
   I would listen to firefighter, the timing has a big effect on fuel consumption. He also recommended a cam for another car of mine that I was extremely happy with. Thanks Firefighter.

You're welcome Green M. Good to hear you're happy with your car. 



Ron

[Paul G]

I just did some reading on cam swaps. Does the K56 have enough lift that I need to worry about coil bind of the valve springs? The comp cam I am running has
gross lift of .298/.303 and lobe lift of .447/.445
                vs the K56 of
gross lift of .336/.336 and valve lift of .504/.504.
These cam numbers have got me 

Comp cams spec from the Summit site.
http://store.summitracing.com/partdetail.asp?part=cca-21-221-4

[Rayzor]

If your installing a new cam I recomend that you get the matched springs. Different grinds call for different pressures that can make or break the cam. At a minimum I would have your springs checked at there installed height and at max lift height before bind. That way you can compare with the cams needs.  Checking the spring bind and retainer to guide clearence should always be looked at. I went with the k54 cam and springs for my 440, but have yet to fire it up.   

[Chryco Psycho]

I agree with Rayzor , get matching springs & check the clearance although typically you are good to .520 lift

[firefighter3931]

Paul, Comp usually recommends the #911 spring for all their hydraulic cams. If you have those installed allready then you're good to go.


Ron

[Paul G]

I called Engle again this afternoon and talked to a different guy. He still wants me to measure the installed height of a pair of springs just to be sure they are at 1.9". Then call Comp cams and see if there springs are about the same pressure as the springs Engle recommends. He said the cam I have is a Chevy grind. 

This guy was a little easier to talk to. We discussed why I want a new cam. What it comes down to is I want more power to fry the tires. It's not a drag car or a daily driver. It is a show & go car, basically I want a tire fryer. He suggests the K58 more than the K56. More lump at idle (sounds better on cruise night) and more top end power. He thinks it will work good with my 2000 stall and 3:55 gears.

Do you guys agree or think I should stay with the K56 to better meet my goals?

[firefighter3931]

I called Engle again this afternoon and talked to a different guy. He still wants me to measure the installed height of a pair of springs just to be sure they are at 1.9". Then call Comp cams and see if there springs are about the same pressure as the springs Engle recommends. He said the cam I have is a Chevy grind. 

This guy was a little easier to talk to. We discussed why I want a new cam. What it comes down to is I want more power to fry the tires. It's not a drag car or a daily driver. It is a show & go car, basically I want a tire fryer. He suggests the K58 more than the K56. More lump at idle (sounds better on cruise night) and more top end power. He thinks it will work good with my 2000 stall and 3:55 gears.

Do you guys agree or think I should stay with the K56 to better meet my goals?

Paul, there's more to it than simply checking the installed height.  You need to consider spring rates (seat pressure/open pressure) and coil bind.  The Comp # 911 has an installed height of 1.90 and enough seat/open pressure & coilbind room for that Engle stick.....these will work with a stock retainer and valve keeper as well. The other option would be to just purchase the springs from Engle.


Personally, i think that the K58 is a little big for a 2000 stall and 3.55 gears. If you want a little more lump at idle have the cam ground on a 108* lsa....i would use the k56. The 108* lsa works fine with headers but if you have manifolds use the 110* lsa.


The Comp cam that's in your car is similar to the factory cam....slow, lazy lobe profiles that don't make much power. The xe256 that you have currently is a good RV/towing camshaft.



Ron

[Paul G]

Thanks guys for all the help so far. I will probably go with the K56 like you suggest Ron. I have a little more work to do before I start ordering the cam and lifters, like sorting out the springs. I have a friend that should have the tools to get the valve springs off to see what they are.

Those Lunati lifters sound like they are a step above a stock lifter. Think I should go with them or get the basic lifter from Engle?   

Do the rocker arms all just come off together as an assembly? Are they adjusted separately or not at all?

I am sorry to be such a pain. I want to learn as much as I can before I start taking my engine apart and maybe prevent some  and the job will hopefully go very  so I can get back to some serious

Thanks guys

[Paul G]

I think this is my torque converter. I have a reciept for a Hughes Performance, 24-20, 2000 stahl, 24 spline converter, I bet this is it
http://store.summitracing.com/partdetail.asp?autofilter=1&part=HUP%2D24%2D20&N=700+400306+115&autoview=sku

This pic is my cam card for the Comp cam I am using right now. It says to use 926-16 springs I have no way of knowing for sure they used them? This link is the 926-16 spec from Summit.
http://store.summitracing.com/partdetail.asp?part=cca-926-16

I think the springs on the car are dual springs like in the Summit picture. I replaced valve cover gaskets a while back but I cant remeber for sure if they were dual springs. I think so?? From what you guys are saying if they are dual springs I would have to remove the inner spring for cam breakin anyway. Is that right? 

[firefighter3931]

Thanks guys for all the help so far. I will probably go with the K56 like you suggest Ron. I have a little more work to do before I start ordering the cam and lifters, like sorting out the springs. I have a friend that should have the tools to get the valve springs off to see what they are.

Those Lunati lifters sound like they are a step above a stock lifter. Think I should go with them or get the basic lifter from Engle?   

Do the rocker arms all just come off together as an assembly? Are they adjusted separately or not at all?

I am sorry to be such a pain. I want to learn as much as I can before I start taking my engine apart and maybe prevent some  and the job will hopefully go very  so I can get back to some serious

Thanks guys

Paul, i looked at the Comp website for the #926 springs....those are a single with a dampner and have an installed height of 1.8in. Probably not what engle would like you to have with their cam. That being said, the safest route would be to buy the whole shooting match from engle....cam/lifters/springs. 

Your rockers will come off as an assembly....5 bolts hold the rocker shafts down and everything comes off together. 



Ron

[Paul G]

Well there it is then. The whole package it is. Will order tomarow.

[Paul G]

Okay another problem. Is my cam gear a single bolt or a 3 bolt? Engle needs to know, so I guess I have to take everything apart before I can order the cam set. I asked about a dual profile, k56 intake and k58 exhaust. He said he can do that but Mopars dont need that. He said that is a Chevy  grind. He was a little surprised that I wanted the k56 instead of the k58 like we had talked about yesterday. I have more time to think about that choice since I have to get it all apart now before I can order.    Since the actual cam cost is only around $160 I am thinking about going with the k58 and if it turns out to be undesirable for me I can move down to the k56 only requiring a lot of work, another $160 and a gasket set.  

Ron, I know you are leaning toward the k56 for my combo which is probably the right thing to do, but I am just wondering if the k56 will actually make more power with my combo than the k58? I think Engle is leaning toward the K58 because it will have a lumpier exhaust note. Which is one of the the things I am after. But if it will hurt hp more than help it is definately the wrong choice. What do you think?

[firefighter3931]

Paul, the k58 is too big with a 2000 stall and 3.55 gears. Will it work in your car....probably. Is it the "best choice"..... absolutely not. Choosing a cam profile is alot more than just about "sound"....you need to trust me on this. 

The k58 is 230*@.050....meaning it's not gonna pull hard until 2500-2800 rpm. Remember that you have a 2000 stall. Now the k56 is 223*@.050 so it will come on stronger down low....closer to your stall speed. Having a tight converter with a big cam such as this combination allways produces disappointing results. The usual comments are allways ; how come my car can't spin the tires ? How come it feels like a dog off idle ? Where did i go wrong ?

I'm here to answer those questions for you before you have to ask them. 

Hey, it's your choice....go for it if you feel the need to experiment. Remember though that once the cam is broken in....the matching lifters are married to that cam, forever. To swap out another cam you will be also into another set of lifters....so that's $160.00 + the cost of a set of replacement tappets. It can get expensive to "experiment". 


In a nutshell ; a cam with a 2500+ powerband using a 2000 stall is gonna leave a big flat spot in your power curve.....and it will be noticable. Going too big on the cam will have the opposite effect of what you're looking to achieve. It won't be a tire frier because it won't be able to turn over the tires due to the mismatched combination. If you were willing to use a 2800 stall and 3.91 gears then the K58 would be the appropriate choice.

On split pattern grinds....yes they do work well in Mopar engines....it's not just a chevy thing.  Typically unported factory heads have a flow imbalance between intake and exhaust, with the exhaust flow being weaker than the intake side. The longer exhaust duration helps by hanging the ex valve open longer to help the engine exhale and decrease intake charge dilution....which makes more power. On a mild combo like yours this isn't as critical because of the application. The k58's .520 lift would also require the valveguides to be trimmed down. Like everything it's a compromise....you could do the head mods and run the split pattern cam but that involves a lot of extra work. Is the tradeoff off cost vs performance worth it in this application....probably not, inmho.


So, there you have it.....that's my story and i'm sticking with it ! 



Ron


Ps. The comp hydraulic cams allways come with a single bolt upper gear unless it was a custom order. If yours is off the shelf it will be a single bolt.

[Paul G]

Thanks Ron. I will stay with the K56 with matched springs and new lifters. I guess what happens is a person always wants more and more. Even if more is not better.

[firefighter3931]

I guess what happens is a person always wants more and more. Even if more is not better.

With respect to cams....this is usually the case. The most comon mistake made is incorrect cam selection. It's better to err on the small side with respect to selecting the proper profile for "your" application. This engine combo will pull hard to 5500 which is about as much as you can get out of a non ported factory head on a 440ci pump gas build. The stock heads are at this point the limiting factor....headflow will largely dictate how much power you can make and where it will stop. The trick is picking a cam that makes the power where you need it given all the parameters/restrictions of the overall combination. 



Ron

[Paul G]

I have the old cam out.  It is going pretty good so far. It is a single bolt cam so tomorrow I can call Engle and finally get the new stuff ordered. I have Lots of questions with pics. 

First pic is of the valve springs. Are these dual springs?

Second pic is of the timing chain which look fine. I guess it was installed straight up. The marks match, if those are the correct marks and it has a straight key in the crank. How would you change the cam timing anyway. Like to actually degree it in?

Third pic is a couple of the rockers. They all look like these two. Do they look okay?

Last pic is the porting work that they did. Hows it look?

I noticed there are holes in the rocker arm socket that the push rod sets in. The push rods are solid. Oil cant pass through. Is this normal?

[Paul G]

The intake manifold gasket is actually the valley pan. Is there an intake gasket set for this or do I replace the valley pan?

[firefighter3931]

I have the old cam out.  It is going pretty good so far. It is a single bolt cam so tomorrow I can call Engle and finally get the new stuff ordered. I have Lots of questions with pics. 

First pic is of the valve springs. Are these dual springs?

Second pic is of the timing chain which look fine. I guess it was installed straight up. The marks match, if those are the correct marks and it has a straight key in the crank. How would you change the cam timing anyway. Like to actually degree it in?

Third pic is a couple of the rockers. They all look like these two. Do they look okay?

Last pic is the porting work that they did. Hows it look?

I noticed there are holes in the rocker arm socket that the push rod sets in. The push rods are solid. Oil cant pass through. Is this normal?

Paul, good work !


(1) those look like a single spring with a dampner and they have been shimmed up to increase the closed pressure....notice the spacers beneath the valvespring.

(2) The lower sprocket on your timing chain set has 3 keyways....one for strait up and the other two corrspond to 4* advance and 4* retard. Each keyway has a different symbol to identify the cam timing's position. Cam timing is adjusted by using the different keyways on the lower gear.


(3) Rockers look fine....evrything is as it should be. It also appears that some mild porting and gasket matching was done.

(4) Use the felpro #1215 intake manifld gasket set. This part number has the heat crossovers blocked off which helps to keep the fuel temps down and eliminate vapor lock and fuel boiling. A thick carb insulating base gasket is also recommended.



Ron