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madtexan · 10-15-2009, 04:35 PM

Hi,

I have a 69 GTO 400 Automatic with AC and was wondering if the cam can be changed while the engine is in the car? If yes, what gotchas will I run into?

I don't know if this question can be asked but here goes: Is $800 a fair price for a shop to R&R the cam (I provide the cam and lifters) if I pull the engine and deliver to them?

Thanks in advance.

mrrat1 · 10-15-2009, 04:44 PM

Can be done with engine in car, radiator/condenser will have to come out. RE $800 thats allot of $$, since you are doing all the hard labor. I did the same job in my 71 GP years ago, didn't have to remove the rad/condenser though. You can do it! Dave K.

goatless · 10-15-2009, 04:48 PM

1st, yes the cam can be done with the motor in the car. It's a big PITA though, especially with A/C. The radiator needs to be removed of course and then the A/C condensor needs to be removed, or at least loosened so it can be lowered out of the way. I was able to do mine without having to open the A/C lines. Lastly you'll need to remove the brace that the horns mount onto in order to get the requird clearance to get the cam out and back in.

2nd, $800 sounds high for a shop to change the cam with the motor out of the car and delivered to them. With the engine on a stand it's a relatively easy job. I wouldn't think it'd take me more than a couple of hours to change a cam with the motor out, allowing easy access to everything. And I'm not even a mechanic.

drevil1 · 10-15-2009, 04:54 PM

No need to remove engine to swap cam. Remove radiator and un bolt vertical brace behind grill , and the cam will just fit in/out. If you have never done it before, you could probably do it in a weekend. If you are familiar with the exact procedure it can be done in a few hours time. I cant speak for the shop price of $800, but dont see a reason to remove the engine. I would bring them the whole car.

David Jones · 10-15-2009, 05:01 PM

I've done it twice.
No sweat, but an aching back.
I did it in car because I didn't have the room or a hoist or an engine stand.
Careful to drain ALL the coolant out of the block.
The condenser needs to be moved and the strut that supports the hood latch will need to be loosened and swung out of the way. I used the t-handle that you pull to open the hood as a helping hand in guiding the cam thru the bearings. Great time to do some detailing and cleaning while you are in there.

madtexan · 10-15-2009, 05:12 PM

Wow! Thanks for the quick replies.

What about the cam bearings? The machinist said they should probably be changed too. The engine rebuild only has about 2k miles on it in the 20yrs since it was put in. One other thing the shop said was that Pontiacs are notorious about the crank & cam not being properly aligned even thoug the marks indicate that they are so he said they would align that correctly. I'm assuming he meant to timing chain marks being aligned.

Why the concern about getting all the coolant fluid out of the block if it's going to stay in place?

I thought the $800 was high but thought I'd check with the experts

Reason i'm doing this is the cam in it is way too hot for the basic stock engine. So the exhaust stinks and the wife gives me grief every time I start it so it hasn't been run much.

The AC isn't hooked up so I guess removing the condenser wouldn't risk any more contamination on the system.

goatless · 10-15-2009, 05:17 PM

Pontiac cam bearings don't wear out that quickly. If they were replaced 2k miles ago they should still be like new.

You need to get the coolant level down below the waterpump holes so that it doesn't spill down into the oil pan when you pull the timing cover.

madtexan · 10-15-2009, 05:49 PM

Quote:

Originally Posted by goatless

You need to get the coolant level down below the waterpump holes so that it doesn't spill down into the oil pan when you pull the timing cover.

What would be the best way to do this? Use a wet shop vac? Draw it from what locations?

thefirebirdm@n · 10-15-2009, 08:40 PM

I drain the water out of the block by pulling the lower radiator hose off the block. Gravity takes care of the rest. Just have a drain pan underneath to catch the water if your concerned about that. By the way, if you were willing to pull the engine to deliver to the machine shop, why not pull the engine and swap the cam yourself. As stated its very easy to do with the engine out of the car.

LPete · 10-16-2009, 11:51 AM

FWIW, exhaust smell is caused by hydrocarbons in the exhaust (unburned fuel). It's caused by misfire for whatever reason: radical cam with lots of overlap, ignition timing advanced too far, single cylinder miss due to ignition problem, compression problem or vacuum leak (one cylinder doesn't usually make it smell that bad). A rich mixture can do it, but it has to be so rich that the engine starts producing lots of unburned hydrocarbons -- REALLY rich.

KEN CROCIE · 10-16-2009, 05:44 PM

madtex--you sure you have an HC-01? We dont normally recommend Rhoads with the HC-01. We do however recommend Rhoads with the HC-02 cam , which would be the higher performance cam for your combo. I missed why you were changeing the cam. If you have any questions or need guidence, please feel free to call me. 909-980-1451

madtexan · 10-16-2009, 06:07 PM

Ken,
Thanks for chiming in.

I'm 95% sure it is HC-01. I bought it about 20 yrs ago. I really don't need to change the cam but the car makes a gawd aweful smell in the house when I start it in the garage and pull it out. It really doesn't run as strong as I think it should. It idles fine with a very slight lope, has decent vacuum.... holds my headlights closed so I assume it is enough vacuum. IT is an AC car but it doesn't work right now. I'm will call you shortly.

Mike

Quote:

Originally Posted by KEN CROCIE

madtex--you sure you have an HC-01? We dont normally recommend Rhoads with the HC-01. We do however recommend Rhoads with the HC-02 cam , which would be the higher performance cam for your combo. I missed why you were changeing the cam. If you have any questions or need guidence, please feel free to call me. 909-980-1451

PontGuy · 10-16-2009, 09:29 PM

Ken, very glad you jumped in to help although its been fun without you. Can you provide your thoughts on how to cam an "original" high compression engine for good street manners/performance with an auto trans given today's gas? Seems like a question that hangs out there but nobody ever really answers. I don't ever intend to go there again (my new engine is set at 9.5:1) but it would be good to know.

Walt

madtexan · 10-16-2009, 11:21 PM

I found some notes and it was actually done in 1995. It is for sure a HC-01 camshaft.

quicksilver97ta · 10-20-2009, 10:43 AM

Quote:

Originally Posted by madtexan

I found some notes and it was actually done in 1995. It is for sure a HC-01 camshaft.

Hey madtexan, I never saw the specs on your cam, do you have a cam card? My car had symptoms like yours and to make a long story short my compression was not as advertised (which I now know is very common), and my cam was at least 4 degrees retarded (even though it was installed dot to dot). Both of those things killed my low end and made my exhaust very rich. I installed a smaller cam and fixed those things and the car was fun again but overall power was lower than what I wanted. I later reused the first cam but upped my compression at least 1 full point and installed the cam 6 degrees advanced to get the intake valve to close where I wanted. Much more power everywhere and very happy with it now!

HJones1313 · 10-18-2009, 10:10 AM

FWIW I've done cams "in-car" as favors before in less than 8 hours, and if you figure $60 an hour, well, do the math; $800 is high. Find a friend to help..

PaulatFast · 10-18-2009, 10:52 AM

Without actually smelling the exhaust, I sure can't tell you what your issue is, but remember a lean condition will cause similar issues. What I can tell you is that cam isn't your problem. As far as your mechanic... I think you have already received enough information to pass appropriate judgement on his Pontiac competance. I would continue to try and diagnose your issue with your current combination.

PontGuy · 10-18-2009, 11:10 AM

Paul,

I guess we got a bit side-tracked on the smell issue when we realized there was a real potential for the valve train to be out of adjustment.. may not be related but seems to me like the first thing to get correct.

If you read through the posts he already replaced the carb with a Cliff-built Q-jet, so mixture shouldn't be far off unless maybe he has a massive vacuum leak somewhere?

madtexan · 10-18-2009, 11:38 AM

Too bad the thread name can't be changed as we move through the diagnosis steps

Quote:

Originally Posted by PontGuy

Now we are crossing posts.

Forget about local parts houses for Pontiac performance parts. They may carry the studs since they were used on Chevy big blocks, but if you want to be sure that you are getting the right stuff then its better to order from the internet. And I would be shocked if you could find the right polylocks for a Pontiac locally.

If you have never set the valve lash it would be good to find someone to help you. Or pull some good instructions from the web. It is important to get it right..

Do you mean to find #1 TDC comp stroke and adjust, then rotate engine and adjust the next one in the firing order and so on? I have the big green service manual for the car and it's probably in there. I have a torque wrench if needed.

Quote:

Roller rockers won't add performance, but I have used them with big cams that require high spring pressures since the stamped rockers can (and will) break under severe conditions.

I just thought Roller Rockers would be cool but I can stick with the stock rockers. Do rollers require more upkeep/ adjustments? Are they noisey?

Quote:

Originally Posted by PontGuy

Paul,

I guess we got a bit side-tracked on the smell issue when we realized there was a real potential for the valve train to be out of adjustment.. may not be related but seems to me like the first thing to get correct.

If you read through the posts he already replaced the carb with a Cliff-built Q-jet, so mixture shouldn't be far off unless maybe he has a massive vacuum leak somewhere?

No massive vacuum leak because it idles ok and my hideaways work fine. but I need to get a vacuum gauge and measure to be sure.

Yeah, sorry we went from can the cam be replaced in the car to I'm trying to fix the smell issue and lack of low end torque to why I put washers under my polylocks. Remember I haven't opened up this car's engine in over 15 yrs so my memory was vague.

madtexan · 10-18-2009, 11:16 AM

Quote:

Originally Posted by PaulatFast

Without actually smelling the exhaust, I sure can't tell you what your issue is, but remember a lean condition will cause similar issues. What I can tell you is that cam isn't your problem. As far as your mechanic... I think you have already received enough information to pass appropriate judgement on his Pontiac competance. I would continue to try and diagnose your issue with your current combination.

YOU guys have shown me much more competence regarding Pontiacs than he did so he's out.

I'm not going to replace the cam because after Ken Crocie, guy who I bought the cam from, chimed in and said that the cam is not too much for the setup and finding my makeshift washers I installed under the poly locks to try to take up the slack.... that's my first problem to remedy. Find the right poly locks/stud combination.

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