Best Camshaft make

who makes the best camshafts?

discovered the #2 intake lobe flat and the lifter cupped at the bottom. I also think the lifters are slightly mushroomed they are very difficult to remove. I've replaced lifters before in other engines and never had a problem. The should just pull right out.

The Crane cam I installed in late May needs to be replaced. Not getting another one.

Hopefully, the ports the lifters are in aren't damaged.

Jeep makes the best cams.

The ones used in the later 4.0s are good torque cams. (99+)

Sorry. Should've specified engine

HT 3.4l V6 Chevy Perfomance Parts engine.

Talked with a few mechanics and they even said Crane Cams suck.

One mechanic said he's replaced half a dozen or so Crane Cams this year and all prematurely failed.

I have run Crane Cams for 40 years with zero problems. I have a Crane in my stroker.

Pulling the lifters will necessitate removing the head. The lifters should pull out the top with virtually no resistance. If it is mushroomed, you will have to pull the cam out the front and drop the lifter out the bottom. I would seriously worry about the block if you have to do this.

The lifter comes straight to the bottom of the bore. The mecks I talked with said the same thing: pull the cam and drop them through the engine and added if the lifters are only slightly mushroomed, the bores are fine. They just warned to count all the lifters and double check everything before installing the new cam and lifters.

One even asked how I broke it in. Told him how (I believe it was your advice) and he said the break-in was fine.

Here's how it was broke in:
Before installation: soaked lifters and push rods in new oil. Cleaned cam of anti-corrosion coating.
1. Slathered cam and lifters with red break-in lube (don't remember name).
2. Adjusted all the valves according to GM specs
3. Used 30W non-synthetic oil and added a bottle or red lube
4. Used new oil filter.
5. Used drill to run oil pump and prime system. did this for ten minutes.
6. Started engine and ran at 1800 rpm for half an hour.
7. Changed oil and filter.

It ran fine up until about 2 weeks ago and then seriously bad vibrations and that's when I discovered #2 intake valve not working.

Ugh. Have to do it all over again.

never heard of crane cams failing besdies engine builders error

Sounds like your lifter failed to "spin" in the bore - which can be caused by either mechanical interference (a burr in the bore will catch the lifter, or enough crud buildup that it gets tight...) or lubrication. What oil were you using? Not brand - specification. There's a lot of talk lately about reduced organometallic content in oils (the new SAE spec - SM, I think? - since most engines are now built with rollerised valvetrains vice the old "slipper" gear.)

It's the oil. The new formuation oil is hard on flat tappet cams. The old oil had high pressure lubricant added but it was found to be bad for catalitic converters. All the new stuff uses roller cams so it won't hurt them. Mobil 1 extended drain is almost as good as the old oils and will keep your cam happy.

5-90 said:

Sounds like your lifter failed to "spin" in the bore - which can be caused by either mechanical interference (a burr in the bore will catch the lifter, or enough crud buildup that it gets tight...) or lubrication.

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The engine was super clean when I put the cam in. and the bores were in great shape.

5-90 said:

What oil were you using? Not brand - specification.

Click to expand...

During break-in: 30W w/a bottle of red assembly lube. The cam and lifter were covered really well with another bottle. Used Castrol 5w-30 synthetic after that w/a bottle of Lucas oil additive.

5-90 said:

There's a lot of talk lately about reduced organometallic content in oils (the new SAE spec - SM, I think? - since most engines are now built with rollerised valvetrains vice the old "slipper" gear.)

Click to expand...

I was warned by several mechanics when I was talking to them about the cam.

Ugh. Another cam job.

Do not use the new SAE "Energy Saving" oils - they're the problem. Organometallic compounds that were previously added as "anti-scuff" additives (like ZDDP) have been implicated in reducing catalyst efficiency, and are therefore all but removed from the new spec. If it's got the SAE "Energy Saving" sunburst on the front, don't buy it for engines with flat tappets. Period.

If you don't have a choice, there's a workaround supposedly using GM's EOS (Engine Oil Supplement,) but it gets spendy rather quickly.

Find an oil with both an "S" (Spark Ignition) and a "C" (Compression Ignition) rating and use that. The new "Energy Saving" oils are not rated for use with Diesels, since most Diesel engines still use flat tappets (and would have a greater problem with scuffing than gasoline engines anyhow, due to higher spring pressures.) Good reports from the field abound on Shell Rotella oil, and I've been using Castrol, Valvoline, and Chevron engine oils with Diesel ratings to good effect. "Newer" ain't always "better..."

And, while synthetics are useful, I'd probably not want to use them on a "new" engine for at least the first 25-30Kmiles. Give the engine time to "lap in" from the machining that was done, then switch to synthetics. This is especially helpful for ring seating - since a small amount of friction is essential to the process (especially for cast iron rings!) Reducing friction during "wear-in" isn't necessarily a good thing, which is why a non-detergent oil is recommended for the first couple of changes. It takes 25-30Kmiles to get rings seated and start a wear and rotation pattern on the lifters anyhow.

Whew!

Duely noted.

The engine only ha s40K on the engine. The compression (measured last week) was 150 psi across all cylinders. Fully new exhaust (magnaflow cat and Flowmaster muffler w/4.0 tailpipe)

What cam maker do you recommend?

Thanks.

pabloconrad said:

Duely noted.

The engine only ha s40K on the engine. The compression (measured last week) was 150 psi across all cylinders. Fully new exhaust (magnaflow cat and Flowmaster muffler w/4.0 tailpipe)

What cam maker do you recommend?

Thanks.

Click to expand...

I used to use Crane and Crower extensively, and Isky as a secondary, but its been a few years since I built engines on a regular basis (damn Air Police...)

I've no particular reason to suspect that any of them have fallen off in quality, so it's a good place to start. I've heard a lot of rumbling about Crane cams over the last year or so - but this was slightly predated by the issues with "Energy Saving" oil - so I can't be certain if it's a matter of a process change on Crane's part, or if it's rumblings about failures due to oil reformulation...

Manditory reading for any pro or amature gear head....
http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech/oil_summary.html

I believe on mod I'm going to do is convert to roller tappets. I don't want to have to do this again in a year or so because of a lack of oil additives or poor break-in procedure.

Now to find matching tappets for the cam.

Any suggestions?

Thanks to everyone.

There are no over the counter roller cams or lifters on the market for 4.0L motors. Haven't seen any roller rockers either.

They would be for a HT 3.4l V6 GM Perfomance engine.

I'm researching them now, but no luck so far.

pabloconrad said:

I believe on mod I'm going to do is convert to roller tappets. I don't want to have to do this again in a year or so because of a lack of oil additives or poor break-in procedure.

Now to find matching tappets for the cam.

Any suggestions?

Thanks to everyone.

Click to expand...

Actually, they've been trying to get interest on the strokers board (groups.yahoo.com/group/strokers) for such a project.

The problem is that there is a basic and critical difference between roller and flat cam grinds - lobes for "flat" tappets have a slight taper. This mates with the slight "crown" on the "flat" tappet (it's not truly flat - it's ground spherical, but with a radius of about five feet...) to spin the lifter in the bore. Roller lobes are truly flat so they don't end up wearing the lifter rollers prematurely - you'd end up chewing grooves into the rollers in short order (and, since they're likely only case-hardened, you'd end up chewing up the roller right afterwards.)

As far as the lifter specs themselves, I think the AMC I6 uses the same diameter lifters as the Chrysler V8, so they should be in the market. You'll have to make sure you can fit tie bars to them (to keep the lifters from turning in the bores) and at least have the OEM cam "ground flat" to get rid of the taper - although, ideally, the much smaller radius of the roller foot allows for a far more aggressive cam lobe profile.

I'm not saying it's not doable - the principal problem has been getting a camshaft grinder to start the R&D work on the lobe profiles and tie bars, and finding a consistent source of AMC I6 cam blanks (which seem to be rather like hen's teeth... Howcumzit I can find cam blanks for a Honda, but I have a hard time finding camshafts readily available for the AMC six? Bugger... I've collected data on all the cams I've been able to find - but they're gradually moving toward "special order items"...)