Cam grinding

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coyote42

coyote42

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Hi, can you guys suggest a cam grinding company? I have a cam too large I would like to resize. Or get one custom ground. Thanks, The car is a 74Charger 3600lb, 318, ported closed chamber cast heads, 9:1 comp, dual plane, hedders, 2.5in dual, 727 auto/rev man, 391 sure grip, 27in tire.
 
Oregon cam grinders, ,courtesy of Rusty Rat Rod's knowledge...
 
What specs are in it now?

At just 9:1 cr, and 3600+pounds, your cam selection will have to be very focused, as the Dcr can fall real fast, making for a disappointing take-off. Eh? Thank goodness for 3.91s
 
Please don't take offense, I am just really curious. With all of the outstanding cams available for small block Mopars, Why would you want a custom grind? I would think that custom grinds would be at the higher end of the performance scale. Just curious. Also, what are your goals?
 
The cam in it is a 230/235 @.050 480,495, 1.5 rocker. 106 sep. Engine wont idle in gear. Idle in neutral is 1800. 2200 summit converter acts tighter than that. I have a Comp 292 cam 244/244 @.050 501/501 lift, 110sep. I got on trade and don't see ever using it even in my 340 for my 67 Cuda. I would like to try and make it useable. My third choice is a mystery cam that came out of the 340. No stampings on it. The lift measures approx. .418/.441 but I have no idea what the duration and separation is. The whole idea with the car is using parts off my shelves.
 
Your tune is waaaay off. The engine has issues not related to the cam size, even though the 230* is too big for just 9/1. For that cam the Compression needs to come up to around 10/1 or better to give some off-the-line punch.
The 340Mystery cam is a much better choice for a low compression teener.It wont make a lot of power, but it will pick the bottom-end up, as compared to the 230 cam.
That 244* cam wants 11/1 or more,compression. At 9/1 it will be a bit of a dog, out of the gate
especially so with a 2200 TC.
Now, whats wrong with your teener. It should idle down to 750ish with that 230*cam ? Thats a nice cam for a 10.5cr engine. I know cuz I'm running a 230/549 cam in my 360. Ima guessing it's sucking air somewhere, or the preload on the lifters is too tight.. If you want some help tuning that combo, thats what some/many of us are here for.
Your combo, if truly a 9/1 cr, has a total chamber volume of about 82cc. The ICA(Intake Closing Angle) of that cam is around 65*. Together they produce a Dcr(Dynamic Compression Ratio), of 7.2 at sealevel. For that engine to be peppy with that cam, the Dcr needs to come up 1 to 1.3 points, to closer to 8.5.This would require the total chamber volume to come in around 69cc, for a 10.6Scr, and 8.36Dcr.This should burn regular gas. Shrinking the chamber volume from 82 to 69, will be pricey.
If you trully want to use off-your shelf parts. That mystery cam should pick up your Dcr a bit.It looks very similar to a stock 340/automatic cam,which was .429/.444 lift. Without knowing anything else about that cam, though its hard to justify throwing it in there though, as the oem 340 cam had an ICA of 66*. Thats pretty much the same as your 230*cam, so no help at all.
If you want to pick up the bottom end of that 9/1 teener, you will need an ICA of about 40degrees. This will raise your Dcr to 8.26. This is a good number. Unfortunately, it would suck as to power. Good take-off, but done real early.
If you put a stock teener cam in there, with its ICA of 50*, the Dcr comes up to 7.86. The 3.91s will help you here, at least until you hit third gear.The stock 69 teener cam is 240/248 duration adv. and lift is .373/.399. With 1.6 rockers, this would jump up 6.67% to .398/.426 . Again, not much power, but a lot more torque.You could probably pull 3.23s pretty nicely,with that.
But all this bsTalk wont solve your current no-idle-in-gear issue.
 
coyote42 said:
The cam in it is a 230/235 @.050 480,495, 1.5 rocker. 106 sep. Engine wont idle in gear. Idle in neutral is 1800. 2200 summit converter acts tighter than that. I have a Comp 292 cam 244/244 @.050 501/501 lift, 110sep. I got on trade and don't see ever using it even in my 340 for my 67 Cuda. I would like to try and make it useable. My third choice is a mystery cam that came out of the 340. No stampings on it. The lift measures approx. .418/.441 but I have no idea what the duration and separation is. The whole idea with the car is using parts off my shelves.
Click to expand...

Neither... I like something around a 220i@ .050 intake lobe/226 @ 050 exhaust lobe, 110 -112 lobe center, will fix it,right quick. My thoughts...
 
AJ/FormS said:
Your tune is waaaay off. The engine has issues not related to the cam size, even though the 230* is too big for just 9/1. For that cam the Compression needs to come up to around 10/1 to give some off-the-line punch.
The 340 cam is a much better choice for a low compression teener.
That 244* cam wants 11/1 or more.

Now, whats wrong with your teener. It should idle down to 750ish with that 230*cam ? Thats a nice cam for a 10.5cr engine. I know cuz I'm running a 230/549 cam in my 360. Ima guessing it's sucking air somewhere. If you want some help tuning that combo, thats what some/many of us are here for.
Click to expand...

I can turn the idle down to 800 in park but it wont idle in gear. that is why it is so high at the moment. Just got it on the road and working the bugs out. Has 15in vacume at carb base at idle with pcv and power brakes. Timing is at 18deg base. Any advice is appreciated.
 
harrisonm said:
Please don't take offense, I am just really curious. With all of the outstanding cams available for small block Mopars, Why would you want a custom grind? I would think that custom grinds would be at the higher end of the performance scale. Just curious. Also, what are your goals?
Click to expand...

No offense taken, Im just tryin a "build it with whats on my shelves" just for fun,because I can. It would be nice to get this heavy car to move better on this budget build if possible.
 
Find any kind of numbers, on that .418"'.441" cam . My guess, something close, to the 340 cam...
 
harrisonm said:
Please don't take offense, I am just really curious. With all of the outstanding cams available for small block Mopars, Why would you want a custom grind? I would think that custom grinds would be at the higher end of the performance scale. Just curious. Also, what are your goals?
Click to expand...

AJ/FormS said:
Your tune is waaaay off. The engine has issues not related to the cam size, even though the 230* is too big for just 9/1. For that cam the Compression needs to come up to around 10/1 or better to give some off-the-line punch.
The 340Mystery cam is a much better choice for a low compression teener.It wont make a lot of power, but it will pick the bottom-end up, as compared to the 230 cam.
That 244* cam wants 11/1 or more,compression. At 9/1 it will be a bit of a dog, out of the gate
especially so with a 2200 TC.
Now, whats wrong with your teener. It should idle down to 750ish with that 230*cam ? Thats a nice cam for a 10.5cr engine. I know cuz I'm running a 230/549 cam in my 360. Ima guessing it's sucking air somewhere, or the preload on the lifters is too tight.. If you want some help tuning that combo, thats what some/many of us are here for.
Your combo, if truly a 9/1 cr, has a total chamber volume of about 82cc. The ICA(Intake Closing Angle) of that cam is around 65*. Together they produce a Dcr(Dynamic Compression Ratio), of 7.2 at sealevel. For that engine to be peppy with that cam, the Dcr needs to come up 1 to 1.3 points, to closer to 8.5.
Click to expand...

It has the closed chamber 302 heads shaved .015 and mild port and bowl work done by me following the head porting sticky on here.
 
Just a general question. What year is the block and has any.milling been done to the heads / deck?
 
mini said:
Just a general question. What year is the block and has any.milling been done to the heads / deck?
Click to expand...

Its an 1988 roller block/ 302 head someone put in. 160psi compression. I had heads cut .015. I did a hone and re ring. When I converted the cam I measured the pushrod length.
 
Is it 18 degrees at 1800 rpm? If it is, it likely has a bunch of mechanical in there as well.

You may have a HUGE vacuum leak. Anything that pulls vacuum from the intake, plug it off. Isolate the intake tract. I missed the carb/intake combo, check baseplate and linkage for interference with the intake. Some carbs have a real issue with linkage interference.

That cam is not that big. I've run 284/484 cams, which are big compared to your cam, in a 8:1 340/360 engines and they ran hard. You need to tune the engine up for what it wants, which in your case is a crapload of initial timing, 24* or so.

Don't drive it at all when doing this. Turn it so it has 36 degrees timing at 1800rpm and start turning the idle down. See if you can get control of the idle. Then put a timing light on it and see if any of the 36 degrees dropped out.

I'd mess with the timing before doing a cam swap... it's a BUNCH less expensive!
 
I also have a oregon cam regrind (ask for Ken) and am happy with it. With that said, getting a cam regound will likely require new/different sized push rods. Probably cheaper to buy a cam and lifters off the shelf with a stock base circle.
 
crackedback said:
Is it 18 degrees at 1800 rpm? If it is, it likely has a bunch of mechanical in there as well.

You may have a HUGE vacuum leak. Anything that pulls vacuum from the intake, plug it off. Isolate the intake tract. I missed the carb/intake combo, check baseplate and linkage for interference with the intake. Some carbs have a real issue with linkage interference.

That cam is not that big. I've run 284/484 cams, which are big compared to your cam, in a 8:1 340/360 engines and they ran hard. You need to tune the engine up for what it wants, which in your case is a crapload of initial timing, 24* or so.

Don't drive it at all when doing this. Turn it so it has 36 degrees timing at 1800rpm and start turning the idle down. See if you can get control of the idle. Then put a timing light on it and see if any of the 36 degrees dropped out.

I'd mess with the timing before doing a cam swap... it's a BUNCH less expensive!
Click to expand...

as stated above....
 
If you have 160 psi, with that 230* cam, Ima thinkin your cr is quite a bit more than 9/1, unless the cam timing is way off.
The cylinder pressure, at 9/1 should be around 140psi.
Your cylinder pressure of 160psi reflects a compression ratio over 10/1, and a Dcr of right around 8/1.
So...............Whats up with that? Is it 9/1? or is it 160psi? Or is the cam-timing off?
 
Oregon regrind is peanuts compared to a new roller. He has a ROLLER block and its pity that he is using a hydro in that. Most regrinds will require adjustables or longer pushrods.
 
AJ/FormS said:
If you have 160 psi, with that 230* cam, Ima thinkin your cr is quite a bit more than 9/1, unless the cam timing is way off.
The cylinder pressure, at 9/1 should be around 140psi.
Your cylinder pressure of 160psi reflects a compression ratio over 10/1, and a Dcr of right around 8/1.
So...............Whats up with that? Is it 9/1? or is it 160psi? Or is the cam-timing off?
Click to expand...

AJ, the book says factory cr is 9:1 on an 88 roller 318, I know that is not exact but with the head cut I would assume its close. It does have almost 160psi wet/ 150-155 dry,cold on all 8 cyl with just a home hone and new rings. I installed the cam with the timing chain set to the 4deg advanced marks. it is 18deg of timing at 800rpm. 15in vac. I know its hard to figure out online but I do appreciate the helpful ideas/direction.
 
Abodybomber said:
Find any kind of numbers, on that .418"'.441" cam . My guess, something close, to the 340 cam...
Click to expand...

Abody, the ONLY numbers in the mystery cam are a C between 3rd and 4th lobes from the dist gear, a 2 between the 1st and 2nd lobe from the dist gear and a 154 between the gear and 1st lobe. /C//2/154$ is how it looks. /=lobes $=gear. If that helps.
 
coyote42 said:
AJ, the book says factory cr is 9:1 on an 88 roller 318, I know that is not exact but with the head cut I would assume its close. It does have almost 160psi wet/ 150-155 dry,cold on all 8 cyl with just a home hone and new rings. I installed the cam with the timing chain set to the 4deg advanced marks. it is 18deg of timing at 800rpm. 15in vac. I know its hard to figure out online but I do appreciate the helpful ideas/direction.
Click to expand...

So I guess what you are saying is; the cam was never degreed in,and the cylinder pressure is between 150 to 155psi,and you have no idea what the true compression ratio is.
Well thats an honest start.
Now you are supplying more erroneous numbers.
-A 230* cam will not likely pull 15 inches of vacuum installed at 4* advance, or with 18* initial, or at 800rpm. Not likely. Id say you're having a tough time.
-Well,there is some good news. The high vacuum tells us a couple of things.Firstly, you probably dont have an intake leak. And secondly the initial timing is at least close.And thirdly the valves are closing, so the valve train is probably ok too, OR the gauge is not calibrated correctly..
-Now lets back up the bus.You have given several pieces of information that lead me to believe that your cam may not be as big as 230*,or it is not installed correctly, namely; the virgin deck height, the factory compression ratio,the cylinder pressure and the idle vacuum.However, for the moment lets ignore that stuff.It could be as simple as 2 bad gauges
-Lets try to get to the bottom of the idle issue. For an engine to run, it just needs 3 things;1)adequate compression, and 2)a correctly timed spark, and 3)a combustible fuel/air mixture. You have them all,cuz it idles at 800, in P/N.
-About the only reason I can think of for your stalling issue is; The carb went rich the moment the tranny went into gear. This would most likely be a powervalve issue.It could be other things as well. If the tranny is slamming into gear, the sudden drop in rpm could signal the powervalve. If the TC is faulty, same story.
-So lets check the TC first, cuz its easy.This is what I would do; Get the back wheels off the ground, rear end on safety stands. start er up,crank the idle down to 850ish,put it in drive,brakes off. Let it idle in drive,wheels turning. Slowly brake them to a stop.Will the engine keep running? If no, the TC is bad, or it dragged the rpm down too far, and its still bad.If yes,it stays running, lets go to the powervalve.
-So the first thing to do is to defeat the powervalve in the quest for a solution.
If you have a metering rod carb, this is easy, just pull the springs out from under the pistons.With a holley type carb, I remove the powervalve and swap in a plug.So after doing that,bring the idle back down to 850, and put it in Drive.
-So what happened?
If it stays running, you will need to recalibrate the powervalve.For the Mrod carb this requires softer springs. For the holley type, a new PV.
If it still quits,I'm outta ideas.
 
AJ/FormS said:
So I guess what you are saying is; the cam was never degreed in,and the cylinder pressure is between 150 to 155psi,and you have no idea what the true compression ratio is.
Well thats an honest start.
Now you are supplying more erroneous numbers.
-A 230* cam will not likely pull 15 inches of vacuum installed at 4* advance, or with 18* initial, or at 800rpm. Not likely. Id say you're having a tough time.
-Well,there is some good news. The high vacuum tells us a couple of things.Firstly, you probably dont have an intake leak. And secondly the initial timing is at least close.And thirdly the valves are closing, so the valve train is probably ok too, OR the gauge is not calibrated correctly..
-Now lets back up the bus.You have given several pieces of information that lead me to believe that your cam may not be as big as 230*,or it is not installed correctly, namely; the virgin deck height, the factory compression ratio,the cylinder pressure and the idle vacuum.However, for the moment lets ignore that stuff.It could be as simple as 2 bad gauges
-Lets try to get to the bottom of the idle issue. For an engine to run, it just needs 3 things;1)adequate compression, and 2)a correctly timed spark, and 3)a combustible fuel/air mixture. You have them all,cuz it idles at 800, in P/N.
-About the only reason I can think of for your stalling issue is; The carb went rich the moment the tranny went into gear. This would most likely be a powervalve issue.It could be other things as well. If the tranny is slamming into gear, the sudden drop in rpm could signal the powervalve. If the TC is faulty, same story.
-So lets check the TC first, cuz its easy.This is what I would do; Get the back wheels off the ground, rear end on safety stands. start er up,crank the idle down to 850ish,put it in drive,brakes off. Let it idle in drive,wheels turning. Slowly brake them to a stop.Will the engine keep running? If no, the TC is bad, or it dragged the rpm down too far, and its still bad.If yes,it stays running, lets go to the powervalve.
-So the first thing to do is to defeat the powervalve in the quest for a solution.
If you have a metering rod carb, this is easy, just pull the springs out from under the pistons.With a holley type carb, I remove the powervalve and swap in a plug.So after doing that,bring the idle back down to 850, and put it in Drive.
-So what happened?
If it stays running, you will need to recalibrate the powervalve.For the Mrod carb this requires softer springs. For the holley type, a new PV.
If it still quits,I'm outta ideas.
Click to expand...

I just had the Holley 600 carb rebuilt and it did this with my other Holley 600. Its a brand new summit 2200 converter. I know the car is an oddball combination of stuff, but that was the idea, to try and make it run for fun. It just hasn't worked. The Offy dual port 360 I had was an experiment, Im going to change it. I have a Torker 340 on the shelf or I will just buy a dual plane for a 318. I will try your suggestions though, Thanks
 
harrisonm said:
Please don't take offense, I am just really curious. With all of the outstanding cams available for small block Mopars, Why would you want a custom grind? I would think that custom grinds would be at the higher end of the performance scale. Just curious. Also, what are your goals?
Click to expand...

Well , yes and no.
A local guy built a couple 460 Fords to power generators for a yacht ( I don't know why not a diesel ) and had cams spec'ed to make peak torque at 1800 RPM
I am a firm believer in custom grinds. They are not significantly more expensive than a shelf cam and with the right grinder , you are not getting a GM lobe / pattern.
I don't think there are " all kinds " of outstanding small block cams out there........mostly compromises.
Re; the original question , I agree that the tune is off. There is nothing in the numbers mentioned that would give you such a poor idle quality.
Not optimum , but not as bad as some I have seen.
The LSA is tight and that will roughen up the idle , but it shouldn't kill it.
 
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