Camshaft Blues

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74swinger360

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So i have been doing alot of reading on here and i think my cam is way to big for the converter i have. I have the eddy rpm cam. Many of you have said that you dont like that cam and i am just curious. I have a 3000 stall 904 with a reverse manual valve body. 3:91 in the rear. Could the cam be the reason i cant seem to get the timing right in the car? Any advice would be great
 
Cam has no affect on timing. If it's not running right, you should work that out first. I don't like the cam, but it should run ok. Just not as strong as some others. What is it doing that makes you think the timing or cam is a problem?
 
It feels like when i am driving down the road and really get into the gas pedal is bogs out really bad. When im in idle and rev it up it revs up really quick and sounds good. I think it is running really rich though because its putting out a pretty good smell and some white smoke (not burning oil). I need to get a adjustable timing light to do this right i believe.
 
I am also interested in this because I have an Eddy RPM cam for my 318. (not installed yet)

74swinger360, are you using this cam for a 360? Are you using adjustable roller rockers? Edelbrock says to use a "thrust button" what is this and are you running one? Any input Moper?

Also, Moper, what is the recommended stall for this cam with a 904 tranny, I have 3:55 sure grip gears as well.....Can you explain why this cam isn't a good cam?

I think these questions will help the both of us....Not trying to hijack, I think we are on the same boat with this cam. lol
 
That cam has an advertised operating range of 1500-6500 rpm, the converter and gears are more appropriate for a cam with a much higher rpm range but that certainly isn't the reason for your bog.

To tune your combination you need to get the timing dialed in before messing with the carb. Many many times the rich smell at idle is due to the fact that you don't have enough initial timing for the mixture to completely burn. You will find that that cam will likely want initial timing in the high teens or low 20's which will require you to limit the mecahnical advance in the distributor to keep the total around 35 degrees. Once that is sorted you can move onto the carb.
 
74, What is the rest of your combo like? carb, ignition, headers, intake, etc... The more specific you are the better.

Dude, I have no clue why Edelbrock says use a button. I didnt think I read that but I have to confess I don't shop that manufacturer for cams. You dont need a button on a small block mopar as the cam is pulled into the block as the engine rotates because of the cut on the cam's oil pump drive gear. The RPM cams are a type of cam I dont like. They are technology from the 80s and they are not very fast rate, nor very high lifts in respect to the intended power curve. I know there are much more street friendly cams out there.. Plus I'm no fan of the lifter Edelbrock uses. The plunger retaining clips always seem to want to pop out of them. As far as stall speeds, there are asmany opinions on this as drivers. As for what I would want, I want something with no more flash stall than you 55mph engine rpm. With 3.55s, a stock type 26"tire that's around 2600-2800 depending. So I'd be looking at a convertor with an advertised stall around 2400 tops. This is a street car setup. A racing setup would be higher, but truthfully a race setup wouldnt be running 3.55s and stock tires either...lol.
 
moper said:
74, What is the rest of your combo like? carb, ignition, headers, intake, etc... The more specific you are the better.

Dude, I have no clue why Edelbrock says use a button. I didnt think I read that but I have to confess I don't shop that manufacturer for cams. You dont need a button on a small block mopar as the cam is pulled into the block as the engine rotates because of the cut on the cam's oil pump drive gear. The RPM cams are a type of cam I dont like. They are technology from the 80s and they are not very fast rate, nor very high lifts in respect to the intended power curve. I know there are much more street friendly cams out there.. Plus I'm no fan of the lifter Edelbrock uses. The plunger retaining clips always seem to want to pop out of them. As far as stall speeds, there are asmany opinions on this as drivers. As for what I would want, I want something with no more flash stall than you 55mph engine rpm. With 3.55s, a stock type 26"tire that's around 2600-2800 depending. So I'd be looking at a convertor with an advertised stall around 2400 tops. This is a street car setup. A racing setup would be higher, but truthfully a race setup wouldnt be running 3.55s and stock tires either...lol.
Click to expand...

Ok Moper, thanks for your explanation, and I'm taking this into consideration...It seems the RPM cam is more trouble than it's worth...What is a cam you would recommend from comp cams to replace the RPM cam? I will have adjustable roller rockers FWIW...duh.. lol
 
couple of things...

you dont need an adjustable timing light if the damper is degreed....

you dont say what carb you are using or distributor...


the reason it rev up in neutral there is no load on the engine....
 
74Swinger340: The Edelbrock cam looks ok from a spec point of view with the rest of your setup. Eddy recommends a 9.5:1 compression ratio for the cam. My books say 10.5-11.0:1 for something in this range. If you're looking at a Comp Cam, the XE268H is going to be close.

MoparDude318: For 3.55 gears on a 318 I suggest a Comp XE250H.

My suggestions are for street engines. I'm sure others will say you can use more cam, and that may be. The LA is easy to over cam. I personally put throttle response over all-out horsepower for a street engine.
 
I have a MSD 6al, Billet distributer, 750 edelbrock performer carb, headers, KB 10:1 pistons, Edelbrock performer RPM intake, and the edelbrock performer RPM cam. Will be installing adjustable roller rockers towards the end of the summer. When i installed the cam i didnt degree it in. I just lined it up with the mark on the Crank shaft. Was that a huge mistake? i meen i ran pretty good when was using the old mopar electronic ignition, just havent figured out the timing with the MSD setup and want to get your guys opinion if there is a flaw in my setup.
 
..........U really dont need MSD on that mild set up on the street.............u could b putting that coin into other things...........kim...............
 
74swinger360 said:
It feels like when i am driving down the road and really get into the gas pedal is bogs out really bad. .
Click to expand...

Usually an indiction of too lean or not enough timing.
I'd reckon you'd want at least 16 initial with no more than abt 34 0f total with your combo.
Try some lighter metering rod springs.Yellows should be good.
Might be a bit much carb bt the 3.91s should help to overcome that.
If the carb is too big the bogginess will be caused by the secondaries opening too early and unfortuneately it's a messy and difficult job to delay them on a performer unlike a thunder which is adjustable in the secondaries.
A bandaid solution to overcome it is to up the jetting to get over the leanness caused by the secondaries opening too early.

Theory being that with secondaries opening too early you have a poor vacuum signal to draw enough fuel so you overjet to compensate.

Just my thoughts on how to make what you've got work.
 
So how would i set my initial timing? is that what the timing should be at idle?
 
Included with the billet distributor was a book and a baggie with springs and bushings. I believe you will end up with using the largest (blue?) bushing and one light silver and one blue spring. That will give you 36° total timing (bushing is 18°), plus 18° initial timing. Second, there are two Edelbrock 750s. What is the list number of the one you have? One is meant for emissions and performance (#1407), and one is meant for performance (#1411). The 1407 will almost always have a lean spot because of the size of the passages in the fuel circuits. You can't change that. So if you have a 1407 I'd look for a better carb.. EIther the Edelbrock Thunder series or a Holley Street Avenger 570.
 
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