Hello all,

I just recently fired up my freshly rebuilt 302. During my rebuild, I installed a comp blower cam: the 284hr blower cam. 35-306-8. The problem which is a relatively small problem, is that the cam doesn't lope enough for my taste. Actually, it seems to lope like my stock cam...

I'm not expecting funny car sound, but I would like a little lope. I do have a quiet exhaust long tubes, h pipe, 2.5 duals to magnaflows (not magnapacks). I plan to install cutouts, so i know that should help some. I'm also on the lean side at idle, but I tuned my carb well to work with the supercharger. Plugs look great.


the Cam should sound similar to this:

Does carburetor tuning have much to do with the sound of the cam lope?

 

I put a bigger cam in my 302 also, big disappointment as far as a lope goes. But it does run better. If you want a big lope go to http://www.cjponyparts.com and read the descriptions of what it does at the bottom.
I have a bigger cam ordered for my 351W I am building to put in my 68 Mustang and the description of it is ..A mild torque converter will be needed as the camshaft delivers superior high end power and a choppy idle.

 

IIRC, the comp cams thumper line may provide the sound you want.

 

Well, my main goal is not sound; it is performance, and so far I've very impressed and am satisfied with the performance of this cam. I have a hunch that my bypass valve may be too small and not bleeding off enough air at idle, so I will be testing it without the supercharged air.

Thoughts?

 

Technology. Newer cams make better power everywhere and are generally more efficient. Valve timings are improved, overlap is reduced, idle is better etc.

Custom cams go the farthest, some of the newer ones out there actually have emission like specs with wide LSA, but make tons of power.

 

That's for sure. Technology has come a long way. I'm just still curious why the cam in the video is as choppy as it is, and mine idles as smooth as my stock cam, but we have the same cam grind... The biggest difference that I can see is that one is EFI and mine is carbureted. I just don't understand. The valve opening and closing events should be identical, and that should dictate the sound. Right? Or am I missing something?

Here is another sample video of the EXACT same cam that I have:

 

Everything else matters too, not just the cam.

 

I understand that. Heads, intake, fuel delivery, immediate exhaust. Correct me if I am wrong (please), but nothing changes the mechanical properties and characteristics of the cam lobe geometry.

My complete setup from air and fuel delivery to exhaust:
Vortech V1 supercharger
Paxton Power hat
Holley 650dp (82651)
Weiand Stealth intake manifold
GT40 iron heads (3 bar)
Ford racing roller lifters
stock push rods and rocker arms (checked the geometry and it was spot on)
Hooker long tube headers with 1 5/8 primaries
2 1/2 inch custom exhaust through magnaflow (not magnapack) mufflers

Tune is still a little lean:
14.1~14.8 at idle
13.9~14.2 at light cruise and moderate acceleration (secondaries still closed)
still breaking in the engine so no boost yet and still below 4K rpms.

Thanks, guys, so far for you help.

 

Nothing about the cam changes, but airflow does. The lope comes from a certain type of flow through the engine...when you have heads and exhaust that compliment the cam, you can prevent that airflow. The lope then goes away. Also, adding fuel and timing can make lope go away, performance engines tend to want more idle fuel, and more timing helps to stabilize flow at idle speeds, the result is a more mellow idle.

 

I like the lope of my Crower. I made this video a few years back after I finished my 351w. Bonus points for Victoria's commentary.

http://vid960.photobucket.com/albums...psupwhhnzx.mp4

Her vehicle recognition skills have improved greatly since then.