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-   -   Ram Air III Cam (https://forums.maxperformanceinc.com/forums/showthread.php?t=867255)

DogMeister 06-13-2023 10:49 PM

Ram Air III Cam
 
How's the idle on the Ram Air III cam? Thinking about upgrading the dinky cam and lifters in my 10:1 long-rod 461. Don't mind a bit of lope but not too gnarly. Enough vacuum for the power brakes?

Gach 06-13-2023 11:49 PM

What cam you have in it now ? I believe Ram air 3 cam is actually 068 cam. Not sure. Ram Air IV would actually better. Specially seeing its a 461.

jhein 06-13-2023 11:53 PM

I think it's pretty mild. This is my previous Melling RAIII cam. To me it sounds more rowdy in the video than it did in person.

https://youtu.be/u1TXdkyh29k

Edit: Oh. Sorry. I see it's for a 461. That's a tiny cam for that CID. That video is in a 400.

Edit again: It's the Melling 068 in the above video, not the 744

Gach 06-13-2023 11:53 PM

Just judging from my buddy Ram Air 1V….400 Idels real nice and nice Lope will make ton of torque in 461.

John Milner 06-13-2023 11:56 PM

If you are talking about the 744 cam, it idles with a very slight loap in a 10:1 433 that I have. I would imagine that it would idle pretty smooth in a 461. It runs well and it produces plenty of vacuum to run power brakes. Low end power is good but I also run a 4 speed and 3:90 gears. An 041 cam is a nice cam in a 10:1 455/461. It would produce plenty of vacuum, idle with a slight loap and make great power.

jhein 06-14-2023 12:06 AM

This is the cam in my signature in a 467. I think it's a little spunky but not bad at all. it has 14" vacuum at idle. Power brakes are solid.

https://youtu.be/ldukr0rEMz4

Formulajones 06-14-2023 07:14 AM

Speaking of the 068, in my 400 it's baby smooth, no lope. It's a relatively small cam all things considered. I wouldn't even entertain the thought of using it in a 455. I'd go straight for something with no less than 230 @ .050 in an engine that large, like the RAIV cam these guys have suggested.
Even that cam in a 455 set up properly will idle pretty docile with only a slight hint at idle and produce plenty of vacuum as long as you have a little bit of compression.

DogMeister 06-14-2023 09:16 AM

Quote:

Originally Posted by Gach (Post 6433332)
What cam you have in it now ? I believe Ram air 3 cam is actually 068 cam. Not sure. Ram Air IV would actually better. Specially seeing its a 461.

Current cam is a Melling SPC-5. which is like the 066 cam. Very mild, 198/208 at 0.050. I think the RA IV cam will be less streetable than the III.

mgarblik 06-14-2023 09:29 AM

The 068 Pontiac cam, sometimes called the Ram Air III cam is a very mild cam. The smoothest, "performance" cam for a Pontiac. Plenty of vacuum, can run with AC, any converter and rear end ratio. Good torque and power to 5000 RPM's. For folks who want a slight upgrade from the ultra smooth 067 run of the mill Pontiac cam, a nice choice. Works in almost any application. Worth 10-15 HP over a bone stock cam.

Formulajones 06-14-2023 09:33 AM

In a 455 it is plenty street able and if installed with Rhoades lifters (I'd recommend) it would idle nearly smooth. In fact you wouldn't even need a stall converter. Just to give an idea how the 455 soaks up that cam, the engine would be all done making power by 5300-5500 tops so it's not a big cam at all for a 455.

Honestly if it's running good now with no issues I wouldn't even bother spending all the time and money involved in a cam swap just to put an 068 in place of the 066. Just not worth it to me.

JB Eng Wis 06-14-2023 09:39 AM

Question Dog Meister.... are you just doing a camshaft up grade?...or will valve springs be involved in a can change also?

mgarblik 06-14-2023 09:50 AM

A well worn 066 cam swap to an 068 cam: You would feel a slight surge in power improvement between 3000-5000 RPM. Some people will notice, some would not. As I mentioned, 10-15 HP. Probably get a little more from optimizing your distributor and carburetor tuning.

Formulajones 06-14-2023 10:00 AM

Yep, in a 455, (a 461 in this case with 10:1 compression) the 068 isn't a big power maker and certainly won't have any lopy idle at all. It would be all done by 4800-5000 rpm.

I've just never been impressed with the 455's I've run against at the Pontiac drags over the decades that follow the small cam mentality. Most all of them can't even outrun my stock RAIII 400, including the HO's and SD's that were in the stock class years ago.

If you're dead set on not using something in the RAIV size catagory, you'd be better served and doing that 455 a favor to at least look at a Crower 242 with a bit more duration and lift than the 068.

Stan Weiss 06-14-2023 10:13 AM

For reference. This is from Cam DR testing that I got from Ken Crocie / H-O Enterp

The Elgin cam as like a 744 and the Crane cam is like a RAIV / 041 cam

; HC-56 Elgin 909
; HC-549 04-12-90 Test # 49
; Rocker Ratio - 1.5:1 Intake - 1.5:1 Exhaust
; Checking Height = 0.004
;
; C1_File_-_Header_Information From Papers
; PVN,ICL,ECL_=_xxx,115.4,115.4
; Overlap_=_76.6
; Intake_Open_=_26.9____Close_=_94.9____Duration_=_3 01.8
; Intake_Cam_Lift_=_.27236____Valve_Lift_=_.40854___ _Area_=_22.79
; Exhaust_Open_=_83.2____Close_=_49.7____Duration_=_ 312.8
; Exhaust_Cam_Lift_=_.27193____Valve_Lift_=_.40789__ __Area_=_24.32


; Crane 969681 Blue Print 041
; HC0235 01-17-90 Test # 35
; Rocker Ratio - 1.5:1 Intake - 1.5:1 Exhaust
; Checking Height = 0.004
;
; C1_File_-_Header_Information From Papers
; PVN,ICL,ECL_=_xxx,113.8,113.8
; Overlap_=_86.1
; Intake_Open_=_31.9____Close_=_98.9____Duration_=_3 10.7
; Intake_Cam_Lift_=_.31374____Valve_Lift_=_.47061___ _Area_=_25.85
; Exhaust_Open_=_83.6____Close_=_54.2____Duration_=_ 317.9
; Exhaust_Cam_Lift_=_.31319____Valve_Lift_=_.46978__ __Area_=_26.58
;
; From a Different Piece of Paper
; 0.050_Overlap_=_8.4
; Intake_0.050_Open_=_1.5____Close_=_50.2____Duratio n_=_231.6
; Exhaust_0.050_Open_=_52.8____Close_=_6.9____Durati on_=_239.7

Stan

i82much 06-14-2023 10:16 AM

seems like we should know more ... weight, axle ratio, tire diameter, transmission, intake, carb, headers, heads, etc.?

if you have a stick with 4.10 gears and 26 inch tires, put a 290b6 in that sumbitch, get a vacuum reserve canister, and let it scream!!!! but you probably don't ...

Stan Weiss 06-14-2023 10:42 AM

Quote:

Originally Posted by i82much (Post 6433403)
seems like we should know more ... weight, axle ratio, tire diameter, transmission, intake, carb, headers, heads, etc.?

if you have a stick with 4.10 gears and 26 inch tires, put a 290b6 in that sumbitch, get a vacuum reserve canister, and let it scream!!!! but you probably don't ...

This is the street section. So I would guess that people drive these cars. The above at 65 MPH would be turning 3450 RPM. Does sound like a fun 2 or 3 hour drive down the interstate to me.

Stan

Formulas 06-14-2023 10:56 AM

A cam that would give you a nice bump from existing cam not break the bank and work with your existing gearing and converter would be the sum 2802

only sticky point would be iff your heads can handle the new lift and thats pretty much a consideration with ANY new cam

i82much 06-14-2023 10:59 AM

Quote:

Originally Posted by Stan Weiss (Post 6433406)
This is the street section. So I would guess that people drive these cars. The above at 65 MPH would be turning 3450 RPM. Does sound like a fun 2 or 3 hour drive down the interstate to me.

Stan

i did it with 3.90's and a 28 inch tire for a number of years ... if you want to know what it was like to have a real hot rod in the 70's, it's basically cruising at over 3000 rpm and desperately watching your temperature gauge every time you sit in traffic 🤣

DogMeister 06-14-2023 11:11 AM

Not looking for major gains. Just realizing that the cam I have in it now is too small for my combo: Long-rod 461 CID, 10:1, TKO-600, 2.5" duals, shorty headers, 3.55 posi. Just changing out cam and lifters, no other mods. Complete rebuild in 2013, less than 5,000 miles on it. Running that dinky cam 4 degrees advanced with #45 small valve heads gave me 459 ft-lb at the rear wheels but only 260 hp. That was with a Quadrajet. Has a Sniper Quadrajet EFI now, but I need to finish a few things up before taking it back to the dyno.

Will most likely go with the Melling SPC-3: 224/236 @ 0.050, 110 lsa. Will run it straight up, realizing a torque loss and hp gain.

i82much 06-14-2023 11:18 AM

IMHO that is still a very conservative cam choice with a wide ratio stick shift, 3.55 gears, 10:1 compression, and fuel injection. Should be a very docile combo. You could easily add another 10 degrees of duration and still have a car your grandma could drive.


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