[64Cat_Jake]

Hi guys,

Long story short I bought a 041 cam from a friend that was offering a comp grind, Comp 852-16 lifters, (plus comp springs, retainers and push rods) for an absolute song - £300!

My car is a '64 Catalina w/ 389ci, 10.5 compression heads, stock log manifolds, iron 4bbl intake, stock converter, stock th400, not entirely sure what the rear gear is, but judging by the ~2000 rpm cruise @ 70mph - its likely to be the stock 2:83 ratio.

The car (will) have disc brakes, new corvette style 1" bore master cylinder, and a 8" dual diaphragm booster, so hopefully low vacuum isn't going to be the end of the world...

The car is only used for fun, once or twice a month, so it doesn't have to be super street-able, just work on the weekends

Question is, how bad is it going to be?

[i82much]

awful. sorry, but that cam is a handful in 400 in a lighter car with steep gears and a manual trans.

[i82much]

rhoads lifters will tame it some but i still think this is just the wrong application for that cam.

[b-man]

Bad.

Awful.

Honestly it’s about the worst cam choice for your combo. The factory issued that cam in Ram Air II and IV 400 engines installed in the lighter A and F-body cars with either 3.90 or 4.33 gears. These engines had free-flowing cast iron exhaust manifolds not unlike tube headers in basic design.

There’s really no reason to use that cam in a heavy B-body car with highway gears and a choked down exhaust system. If you use it misery awaits.

[i82much]

square peg. round hole. so to speak.

[4zpeed]

If that question would've been answered
any quicker, it wouldn't have been asked.



..,.........


Frank

[64Cat_Jake]

Don't get me wrong, I know this isn't the right choice really, I'm just wondering how awful its going to be... The car only gets used for joy rides, so I can tolerate a rough idle and having terrible road manners. The choppy exhaust is something Im excited for.


The long term plan is to go to a T56 Magnum and push the gearing to something in the mid 3s, but thats a few years down the line.

There is a EngineTech 068 clone on Rockauto thats pretty cheap and is a tempting half way....

[b-man]

Get the 068 and enjoy the nice exhaust rumble and more than decent drivability.

Much better choice.

If you had a 455 then the 041 would be doable.

[i82much]

have you ever run a big cam in a street car? it’s pretty annoying. manual trans, gear, compression, and light weight, and a big all help, but you really only have compression.

my father had a 305 c20 that he put a mild “rv” cam in. with lazy rear gears and an auto, it literally could not climb over a curb.

[steve25]

Go for that temptation and sell off that 041 cam or check into getting it reground because your looking at a full on nightmare!

There’s no weekend fun to having to put a auto trans car in neutral at stop lights when warmed up no less when still cold! Been there done that!

That original AFB carb will need to be sent out and reworked to run right with that Cam and if you buddys push rods are for 1967 and up heads you can’t use them anyway!

[64Cat_Jake]

Originally Posted by i82much

have you ever run a big cam in a street car? it’s pretty annoying. manual trans, gear, compression, and light weight, and a big all help, but you really only have compression.

my father had a 305 c20 that he put a mild “rv” cam in. with lazy rear gears and an auto, it literally could not climb over a curb.

Nope, this is my first adventure into building Pontiacs, I've done a lot of reading, but very little experience in what the change in duration and LSA translates to on the road

Worst case, I can always throw the old cam and lifters back in

[Half-Inch Stud]

That cam is just fine in a 455 or 428.

I simply don't know how the 400 will do in a 400, probably okay in a Stick with 3.55s gears, but not with the highway 2.73:1 rear gear and stock converter. 068 cam will feel powerful.

[mgarblik]

Don't get me wrong, I know this isn't the right choice really, I'm just wondering how awful its going to be... The car only gets used for joy rides, so I can tolerate a rough idle and having terrible road manners. The choppy exhaust is something Im excited for.

You have accurately described most of what you will be "enjoying" . You can add an engine that will have to be bumped into "N" at most traffic lights, or be hard to hold at a stop light because of the high idle speed needed to keep it running in drive. Dieseling when you shut it off, unless shutting off in gear or adding an idle stop solenoid. Inconsistent ability to stop the car due to low vacuum to the brake booster, additional blowby, because of inability of PCV system to operate properly due to vacuum issues. Main metering system problems unless the carburetor is re-calibrated to work with available vacuum and rough , stumbly acceleration from idle to 3000 RPM's when that cam begins to work as designed. Plan on changing spark plugs a couple times a year as well, not a big deal. Overall, a lot to give up for an exhaust rumble. I have run that cam in a number of stick shift cars with a decent rear gear. From 4000-6200 RPM, strong performer for a factory camshaft.

[64Cat_Jake]

Originally Posted by steve25

Go for that temptation and sell off that 041 cam or check into getting it reground because your looking at a full on nightmare!

There’s no weekend fun to having to put a auto trans car in neutral at stop lights when warmed up no less when still cold! Been there done that!

That original AFB carb will need to be sent out and reworked to run right with that Cam and if you buddys push rods are for 1967 and up heads you can’t use them anyway!

Oh forgot to mention, its an 750 cfm Quadrajet on top

Havent heard of this before, what causes the need to drop it into neutral at a light?

[64Cat_Jake]

Originally Posted by mgarblik

Don't get me wrong, I know this isn't the right choice really, I'm just wondering how awful its going to be... The car only gets used for joy rides, so I can tolerate a rough idle and having terrible road manners. The choppy exhaust is something Im excited for.

You have accurately described most of what you will be "enjoying" . You can add an engine that will have to be bumped into "N" at most traffic lights, or be hard to hold at a stop light because of the high idle speed needed to keep it running in drive. Dieseling when you shut it off, unless shutting off in gear or adding an idle stop solenoid. Inconsistent ability to stop the car due to low vacuum to the brake booster, additional blowby, because of inability of PCV system to operate properly due to vacuum issues. Main metering system problems unless the carburetor is re-calibrated to work with available vacuum and rough , stumbly acceleration from idle to 3000 RPM's when that cam begins to work as designed. Plan on changing spark plugs a couple times a year as well, not a big deal. Overall, a lot to give up for an exhaust rumble. I have run that cam in a number of stick shift cars with a decent rear gear. From 4000-6200 RPM, strong performer for a factory camshaft.

Ah, thanks for the insight. I see now why a higher stall converter is needed, makes sense.

Looks like this might be curtains then, I'll stick it on the shelf and wait for the other modifications to happen. It might become a street/strip car one day (but lets face it, it probably won't)

[steve25]

Carb and timing tuning factors that are related to engine vacuum levels that go unaddressed.

Jake, the guy I work with has a great saying which is this” Some people are flat out dumb and you walk by them and never know it , but then some people are dumb and they have go set about to prove it to the world!

Don’t be that dumb person please!

That factory never used that big a Cam in any production line 389 motor, even in far lighter cars then yours and with far more rear gearing!

There’s no weekend fun to driving a car that sounds hot , but yet the neighborhood 19 year old punk blows you into weeds from a stop light in his civic with only a loud muffler and air cleaner as a mod!

[4zpeed]

That cam is meant to be used in a higher RPM range, it is not meant for mid or low RPM usage, simply doesn't work.

You can make good power with the 068 and it will only enhance your future upgrades, RPM range dictates cam usage.

Take the time to do a little homework before you make a decision if your looking for power vs. a nice lopey cam sound.

From the TECH THREAD ARCHIVE - http://forums.maxperformanceinc.com/...d.php?t=644938


Best of luck!
Frank

[nmoreilly]

As others have said, put in the 068 and enjoy he car. 041 will be horrible in that combo

[mgarblik]

Don't be disheartened by my harsh realizations and others here. Most of us have been there, once or more times. As mentioned, an 068 factory cam or something similar will have a manageable lopey idle, plenty of low-mid-range power where you can use it with that heavy car and highway gear. Should make 320-350 HP if the engine is healthy and tuned properly. You will be much happier. Have some fun with your car!!

[i82much]

the only other thing i would say is this. if you are hard-headed enuff to put that cam in your car, we are probably distant relatives because i would do the same dang thing.