Cam suggestions, please

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Bill Crowell

Bill Crowell

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So I built a 360 LA with 10.5:1 static compression, heavily-ported "J" heads, Edelbrock Performer intake (match-ported) and a big ThermoQuad with a Torqueflite 727 and 2,200-stall converter. The cam is the Comp Cams hydraulic 20-243-4, the so-called "292" cam (236 degrees of duration at .050, .480 lift).

This cam is obviously too big for my 2,200-stall converter. The converter really drags the idle down badly; the combo is definitely not very street-friendly; and I don't think using a higher-stall converter would tame it down much for street driving, so I think I'd better install a smaller cam.

I'd appreciate any suggestions you might have for a more appropriate cam. Thanks very much.
 
A Convertor matched to your combo can be very streetable. I was running a similar combo with a Dynamic 9.5" Convertor with 3600 stall. Worked well on the street even at lower rpms, of course depending on your rear end ratio.
 
1970A-66Chally said:
A Convertor matched to your combo can be very streetable. I was running a similar combo with a Dynamic 9.5" Convertor with 3600 stall. Worked well on the street even at lower rpms, of course depending on your rear end ratio.
Click to expand...

Agreed.

I'd like to know more about that cam too. Like the LSA? And your timing? And the rear gears.

Dynamic made me a 9.5" 4000stall. That was a really nice and very efficient convertor.
 
2200 stall is not enough stall for that cam.

Bigger Stall is a must. (3500 rpm)

A Smaller cam with Ported head is just making a bigger "mismatch combo!"

First thing you need to do is get a lot more initial timing. Big cam, and Ported head need a lot more timing than you might think. 20 -25 degrees. before your thru, you will need to recurve you dist.
 
IQ52, you are right! The cam card was filled out incorrectly. It is a bigger cam than I thought! Yes, the motor does make some "pawful" sounds.

I didn't know that a much higher-stall converter would be streetable. Maybe I'll give that a try!

Thanks, everybody!
 
Bill Crowell said:
IQ52, you are right! The cam card was filled out incorrectly. It is a bigger cam than I thought! Yes, the motor does make some "pawful" sounds.

I didn't know that a much higher-stall converter would be streetable. Maybe I'll give that a try!

Thanks, everybody!
Click to expand...

Just make sure you tell them it is for a Street Car. They will have it tight enough for street driving and still streeeeetch to full stall, when that lead foot comes out.:burnout:

Today's converters are light years ahead of yester years!!!!
 
I believe one of dynamics 9.5 converters they call the pro street .
They are suppose to be real street friendly .
I have one just not installed I think the one I have is a 4200 .
Call dynamic converters and tell them what you have they will fix you up .
 
Bill Crowell said:
The converter really drags the idle down badly.

I'd appreciate any suggestions you might have for a more appropriate cam. Thanks very much.
Click to expand...

the age old question ....how much initial timing are you running?
 
To give you an idea on convertors mine is a 3500 and if you drove my car normally you'd never know it was anything but stock. YOu even feel it bump when you put it into gear.
 
You have to choose between a converter or cam.Personally for the street a smaller cam might make you happier but you also want look at the driveability if street only .Good converters arent cheap compared to a cam and the correct cam can sound like what you have, but still make plenty of torque for the 2200 converter.The bigger converter bigger cam dont always make a street car enjoyable to drive.
 
Wow, thanks a lot everybody for your great suggestions! I see where I went wrong now, and I've got a plan for the V-200 more door:

1. 3,500 stall converter
2. Much more initial advance.
3. Re-adjust the ThermoQuad; and
4. Play with the advance curve

Thanks again. I really appreciate it, and will report back (might take me awhile).
 
Bill, if you are a streeter;
I went thru three cams in a hurry trying to make my combo streetable.
My first was a Chrysler 292/508/108 cam. Too big! heres the deal tho it was 248 or so at .050. So 292less 248=44* worth of ramps. Thats pretty fast.
You say yours is 292 with 236@050, so 292 less 236 =56* worth of ramps. Thems pretty slow ramps.Easy on the lifters, but small cam with big cam sound. That 292
is stealing idle torque big time. And the tight TC is proving it.
Furthermore in my OOTB Eddies that cam didn't start waking up til 5000 or so, and loved to go into the 7000s. That 5000 is about 50 mph in 2.45first,with 3.55s. But the getting there, with a 2200TC would be kinda boring.
So you have a choice; A) more rear gear,or B) a lower tranny first, or C) a higher stall TC,or D) a smaller cam that comes on sooner and is done a lil sooner, or E) some combination.
I choose D). I went to a 276/515/110 cam(intakespecs) that is 230*050; and 276 less 230 is 46* worth of ramps. Then I swapped rocker arms to get .549 lift.
The result was tons of lowspeed torque, pulls right off idle, and keeps on pulling to well past 6500.( I usually shift at 7000/7200)I swapped gears around and ended up with a 10.97 starter gear, so I hit 37mph at 5000 now, but it is spinning the whole way. In fact it keeps on spinning and spinning.(lousy street suspension).
Notice, my cam is 276advertised,230@050.. Pulls right off idle
.......and yours is 292 advertised,230 @050..not so good idle
My Scr is 10.7 to your 10.5;but I am running aluminum heads, so your combo might actually have a better effective C/R with the iron heads.

44* worth of ramps is about as fast as you will find. FWIW, the 230 cam, once I got the idle timing figured out and the fueling right;sorry, it idles kindof like a stocker. Even at 700 I can hardly tell it is in there. Once it get's under 600/650 I can start to hear mine. Just before it stalls it gets to the rumpity rump. Very sneaky at the stoplite.Until I stand on it, then look out! That's what adequate initial timing will do.Mine likes about 18* idle timing, maybe a bit more, but I give it only 14 to 16, cuz I bring in a ton of Vacuum advance to smooth her right out when PT cruising.
If you just have to have the rumpity-rump; I suggest, if you haven't already, get the T-port sync dialed in and jack in the idle timing.Yours would probably want as much as possible, until the starter complains; maybe 18 to 22. And unless you get it there your T-port sync will be out, and that don't help with a 2200TC.
The closer your T-port sync gets to ideal,together with the greater advance, the higher will be your idle torque,and the lower you will be able to set your in-gear idle.
Do not run hard until you get the power-timing adjusted.
Then if it's still sluggish, it's time for a; TC, or rear gear.
 
AJ/FormS, that was a really thoughtful post with lots of new information. Thank you very much for going to the trouble of replying in such detail. I am printing this thread out to keep forever!

However, as IQ52 pointed out, my cam has 244 degrees of duration at .050, not the 236 degrees that I had thought in my original post. (Danged parts house filled the cam card out wrong.)

So I guess that means I have 48 degrees of ramp rather than 56 degrees. Do you think it should therefore idle fairly decently with the right torque converter, timing, etc.?
 
Bill Crowell said:
AJ/FormS, that was a really thoughtful post with lots of new information. Thank you very much for going to the trouble of replying in such detail. I am printing this thread out to keep forever!

However, as IQ52 pointed out, my cam has 244 degrees of duration at .050, not the 236 degrees that I had thought in my original post. (Danged parts house filled the cam card out wrong.)

So I guess that means I have 48 degrees of ramp rather than 56 degrees. Do you think it should therefore idle fairly decently with the right torque converter, timing, etc.?
Click to expand...

Yeah 48 is getting there.
As you have discovered,that cam really has too much duration for a street 360, with an automatic, unless you put a big TC and 3.91s,behind it.. It will idle so you know its in there. But in a heavy car, it will be all bark and no bite until it gets wound up some. In a lightweight A, and properly matched, it will haul the mail all right. Been there done that; I'm done with that size cam. It was fun for the summer, but then it was over.And I have never missed it.
So, Because you said you have heavily ported heads, I would order up a custom cam. One to take advantage of the head-flow, but limited in duration, and street-friendly.Ima thinking mid 220s to low 230s; say about 228*@050.
Be forewarned tho, that the TC may still have to go. 2200 is pretty low. With your 10.5Scr, the 228 cam will make plenty of idle torque, and while you can probably tame it some with late timing,that's not really the way to go, nor is standing on the brake pedal.
A quick trip to the Wallace Dcr calculator show that you may have to lower your Scr to run a street-friendly cam.Inputing a 64* ICA, on a 276/110 cam(possible specs for a 228* cam) @ 10.5Scr the calculator spits out 8.4Dcr and 169 psi cylinder pressure. While 8.4 is fine for aluminum heads,as stated here on FABO by experienced users, iron heads have trouble with 8.4; and 8.0 is generally thought to be the high limit for them, and pump gas.This is where a higher stall TC, say in the 2800 to 3200, can help get the engine through the sensitive zone. Not the best idea, but it may work.
Retiming the cam to 108ICL, sets the ICA to 66*, and drops the Dcr to 8.27, and pressure to 166psi
Reordering the cam on a 112 LDA, installed at 110,sets the ICA to 68*, and drops the Dcr to 8.1, and pressure to 163.
So now it's getting really close. The above was using the slow ramps of 48* to achieve 276 from 228.
Faster ramps, like the 44* stated earlier would allow 228+44 = 272 advertised. That puppy ground on a 114LDA, and in on 112, would yield an ICA of 68* again, dropping the Dcr to 8.1/163
But more interesting is the flipside of those 44* ramps. Taking 276 less 44 gets you a 232@050. That's almost a full size bigger cam for the same advertised. Installed with the same 68* ICA gets you the same 8.1/163. But now you have LDA choices. You can order any cam from 110LDA to 114*LDA. But always installed at 110, for a 68* ICA. Hmmmmmmmmmmmm
I know, clear as mud. The point is call your cam guy. Answer all his questions truthfully, and trust him.Order the fastest street ramps for .904 lifters,that he will sell you,and with as much lift as your headflow needs,and you will be golden.
 
I would look for something along the lines of 224/230 or 230/236 .050 numbers. I would still go for a 3000-3500 stall converter as long as it custom built (9.5") for the application. I would also look at upgrading the Performer intake to a Performer RPM to match the rest of your combination or port the Performer intake.
 
AJ/FormS said:
Bill, if you are a streeter;
I went thru three cams in a hurry trying to make my combo streetable.
My first was a Chrysler 292/508/108 cam. Too big! .
Click to expand...

I've tried the MPP292/509 cam and the MPP284/528 cam. Both with the same engine and the same 3500 convertor. Not a huge difference in duration @.050. But a huge difference in LSA. The difference I found was a more streetable combo, better idle and the car also went faster.
 
roccodart440 said:
I've tried the MPP292/509 cam and the MPP284/528 cam. Both with the same engine and the same 3500 convertor. Not a huge difference in duration @.050. But a huge difference in LSA. The difference I found was a more streetable combo, better idle and the car also went faster.
Click to expand...

What was the LSA of the one that idled better?
 
"sledger46...I would also look at upgrading the Performer intake to a Performer RPM to match the rest of your combination or port the Performer intake."

But sledger46, I'm koo-koo for dat spread-bore TQ!! Even if the square-bore carb is faster, the spread-bore makes much more impressive noises! You gotta be able to scare the hell out of your passengers, right?
 
If the TQ is set up correctly, it will make as much or more power than a square bore.

Your converter is too tight. 2200 is a barely warmed up stocker. The days of needing to use small cams becuase of junk converters is loooonng gone. Use the CORRECT cam, with the CORRECT LSA and the CORRECT converter and it will be quicker, faster and better to drive.

I run 255 at .050 in my daily driver. You wouldnt know it. If your tune up is right the engine wont know what the at .050 is. BTW, that is on 340 CID and a net .600 lift. And its on a 105 LSA in at 105.
 
YR your cam is about as big at .050 as the comp hyd after lash no less on a 105 lsa which makes it less streetable .Why for a streeter would you spend 450 plus for a converter when a simple cam change can be a ++ and have it enjoyable to drive? I just cant understand the reasoning to spend more and not be happy with it.I agree with AJ 100%, but you can have a cam to work with your 2200 conv. and be happy with it. Yes he could just keep spending until the cows come home (heads,cam,converter, carb,whatever)but why???
 
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