Oh please no! Not another 041 thread
 

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?

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

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

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.

square peg. round hole. so to speak.

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



..,...https://mystudentapt.files.wordpress...04/babyceo.jpg......

:popcorn:
Frank

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....

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.

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.

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!

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

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.

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.

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?

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)

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!

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

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

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!!

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.

:beerchug: :D

Sounds like a sensible course of action!

To be fair, there are a lot of corners here in the UK, first turn Civic Boy is probably disappearing ahead anyway! :pound:

Are you sure you have the actual 041 comp grind? Do you have the part number? Compcams sells 2 different cams as 041 replacements. One is a copy of the actual old 041, the other more common grind from comp uses their more modern magnum profiles. The later is more streetable in 3.75 stroke engine.

Okay I think I am gonna get flamed. Most will say not an apples to apples.
I don't have a 041 but close enough. It is an H-O Racing HC-02/744HL with 231 /243 @.050 on a 113* LSA, .513 lift with 1.65 rockers. No Rhoads lifters. It's in a 400 with aluminum heads at 10.1:1 . Street n strip TH350 with 2800 stall torque converter, 3.07 gears. It does have a lumpy idle, but I've heard lumpier in other 'street' cars. In my 68 Firebird. Riding on the dreaded (hard) BFG T/A's. Idles at 750 rpm in drive with 11" vacuum. It is finicky to start, and won't idle until until it gets some heat into it. The power brakes require more effort when idling out of the driving otherwise they are just fine. From a standing start it will roast the tires through first and well into second because of the non sticky tires. From a rolling 20 mph start the car goes, but the tires break loose when the cam hits it's power band in the mid 3k and up rpms. While doing errands around town, at a stop light the cooolant temp will rise over 200* F, but comes down once I'm rolling again. I'm sure the higher stall torque converter makes it a bit more driveable. I enjoy driving it, others may not. Others may not even enjoy a ride along.
If you have any trepidations, it would be better to err on the cautious side. If the 041 cam & kit are new, I think it would be easier to sell than used, even if for a short amount of time.
The previous engine in that car was another 400, about 8.5 :1 cr with a cam similar to an 068, and stock converter. It would 'squawk' the tires; nowhere near a 'roasting'. It was also quite a bit fun driving it, but I like the new one a tad bit better.

You obviously are more interested in getting looks to actual performance based on your own admission. Given that, I would recommend a milder cam and installing triangle wheels. You will get the same “omg, what a tool” looks at the cruise ins and much better performance.
Aka. Not a good choice no matter what a one off might say....

Also no one has said anything about the compression ratio, as that is not the subject of this thread. I will digress as that is known to happen on this site. From some of the info I have gleaned from this site, if your 389 is actually 10.5:1 compression ratio, a 068 may be too small for that CR and you would run into detonation difficulties, unless your UK gas has a higher octane rating. Pontiac rated their ratios about 0.5 points higher, so you may actually have 10:1. Only real way to know is to measure every thing: combustion chamber size, piston valve relief/dish, distance piston is down the hole, etc.

i think the converter makes a huge difference. a stock converter is going to put a huge load on the OP’s engine compared to your converter. the idle RPM drop from park to gear is going to be huge no matter how much he tunes it.

The compression plays a huge part here!!

The HO racing high lift 744 cam still has 76 degrees of overlap, the 041 has another 11 degrees on top of that, while the very street friendly 068 cam has only 63 degrees of overlap.

The 068 cam in a 400 with # 48 heads ,with tuning while pumping thru RA exh manifolds and dynoed while just driving the water pump has made 370 hp so it’s no wimpy cam.

In terms of a fresh top to bottom 389 rebuild and with what those heads flow you would be doing very well to make even 325 hp with a 068 cam.

I experienced a 041 389 combo once in a 1966 GTO 4 speed with 4:11 gears. Was a blast to drive, .... stock converter automatic 2 something gears ?
Probably not so good,
Your your going to NEED to learn carb calibration to even get close to acceptable driving manners
Iam not talking just idle screws and speed

60% or more of that great 389 blast was due to the 4.11 gears I assure you!

You know back in the 80s when I mainly did autocrossing there was another guy with a 78 Firebird with a low compression 400 that had an 041 in it that ran OK. Was not supposed to do a cam change in "stock" class but did and got away with it.

But I agree with an 068-one of my local friends that builds and turns a lot of different Pontiac uses that as his go to cam for 389s, 400s and even 455s. His quote "has a little lope and roasts the tires" !

That's why I included the gear ratio, I assure you 25
And that's why I insinuated that with a 2 something gear and stock converter it wont work great

Contrast by context

.

Plus the pontiac diehards here hate to see anyone put a combo together that will be a dog out of the hole. A stock 389 with a 041 cam in a big,heavy car with tall gears and a stock converter will probably be a embarrassment to the pontiac pride. Ive seen some pontiacs on youtube trying to be a hotrod and all i do is feel sorry for them.

Yup, the you I was referring to was the OP of this string.

Then there is the economical approach of a Summit 2801.

Put the 041 in with a set of Rhodes lifters. I doubt you'll have to put the car in neutral at a stop either. It will be a little fussy and flat at low speeds but will sound glorious.

Well, there's been plenty to read here - probably going to put the 041 on the shelf for the time being, till I can get an overdrive manual and lower the rear gears - Rhoads lifters seem like a good idea

Yeah I have been looking at the k2800/k2801 - They seem like great value

The other option would be to just get an EngineTech reman of a 068 and use the Comp lifters I already have (given I'd need to use Rhoads with the 041 anyway)

Here is yet more Caming suggestions handed down through the ages!

I love old charts like these, thanks for sharing!

It does raise an interesting point, I wonder how much advancing the 041 4-6deg plus Rhoads lifters would tame the cam

Well the rump of the 041 cam and noises of a hot valve train with Rhodes lifters should fill your sonic needs for the car, but with these lifters I would only advance the Cam 2 degrees which takes care of normal timing chain stretch.

Q-jet wise in the least you will still need to run A lighter power piston spring and then with the motor hot confirm that idle mixture screw have good effect when being moved both in and out from a mostly decent idle setting. If the Q-jet you are running is not off a 68 to 70 motor then I do not think you will get a high enough hot idle out of the motor without also having a off idle stumble.

In this case the air bleeds need to be reworked and while kit’s to do this are sold, you might just want to send the Carb out for this work if you’re leery of doing such yourself.

There has been a ton of discussion on the subject of install position on the 041 cam around here. Generally most seem to like that camshaft in the 108-109 ICL position. With a 113 LSA that's 4-5 degrees advanced. With a 114 that's 5-6 degrees advanced. Depends on who's cam card you look at.

If it were me in your shoes, I'd take the suggestion of using the 2801 camshaft for your application and have the added benefit of some additional lift over an 068 without the need to increase rocker ratios. It's a very mild camshaft for a 389-400.

I've exploited the 068 for all it's been worth, it's not a big camshaft at all, idles baby smooth, and is an "okay" performer. Not something I'd consider worth while going through all the trouble and expense for just a camshaft swap.

Thats some interesting points to consider too. I recently rebuilt the Q Jet that I bought of an old boy here in the UK - the carb turned out to be from a 76 Pontiac 400. It works just lovely! Was out in the garage yesterday in the 25F cold, started as soon as fuel hit the fuel bowls! Was pretty happy with that!

Unfortunately, being in the UK there isnt really anyone I can send it too. (Its not the period correct carb anyway, so it would probably be more cost effective to just buy a new Edelbrock AVS2 or Holley or even EFi) Thankfully I have friends with decent machining equipment so would probably machine it myself.


I forgot to mention, as part of the deal, I got some Comp 1.65 rocker arms. Rather than jump in with the two feet, I could stick them on the stock cam in it, measure the performance. Then go to the 068/k2801 with 1.5s, measure. Then with the 1.65s, measure... etc

SCIENCE!

I like those ideas :beerchug: I love experimenting with stuff to find what works best. If you're on a budget you might find the 1.65 rocker upgrade with the current combo satisfactory. It's certainly easy to do and doesn't take much time.

If you don't have pushrod clearance, those 1.65s probably aren't a good idea. :sorry:

Yessir! Will report back in the summer!

Off topic, but I watched the vid in your signature - your car sounds ace!


Yeah plus they are mid 60s heads, so the shallower valve angle isnt great for really high lift either.... Got to work with what ya got and measure twice haha

I also got a set of Comp springs and retainers as part of the deal, I they were specc'd for the high lift and I have a feeling that they have a taller seat height too

Lots to think about!

Sorry about the Carb send out recommendation, I forgot where you live.
Do
You know the part number of the springs?

What color strips are on them and are they a single spring with a inner flat wire damper, or duel springs?

The 041 is actually just about the perfect cam for a 400 build when used in the correct application. That means RAII or RAIV heads, manual trans, and at least 3.90 gears. It also requires high compression, otherwise the 80 something degrees of overlap KILL idle quality, power right off idle, power in the "normal" driving range, etc.

Rhoads lifters help some with that scenario if you aren't up near 11 to 1 for compression, but IF you really want to see how well the 041 cam works in a 400 build the engine just like the factory did, and set the drivetrain up to effectively use that kind of power.

As far as the carb, moving to an Edelbrock AVS or Holley, or some sort of TB electric unit is just going backwards......IMHO. I've exploited my 1977 Pontiac Q-jet (same as your 1976) for over 3 decades now and NOTHING will outrun it on the dyno or at the track. Plus it gets excellent fuel economy for "normal" driving, instant starts in any weather, and has been dead solid reliable all these years.........FWIW........Cliff

Just don't do it!!! Find an 068 cam and you will be much happier!

IMHO I would use the use the Summit 2801, the specs are much like the 068 but give you some more lift (which always improves power) and some lope. You will want to use new valve springs as the old ones are probably "used" up. Lots of advice and opinions here; take your time to sort it all out. Best of luck with your decisions.

(Everyone is basiclly right, the 041 is too much for your current engine and car build, be happy--go smaller.)