[Nickv]

found out that I have two wiped out cam lobes. I wondered why at full throttle in 3rd gear RPM's built slowly and car was out of steam at around 5000rpm. The existing CAM is a CC292. The car is a 67 GTO, weights 3480. Ran a best of 11.5@118 on motor and best of 10.8@123 with 150 shot of nitrous. It is a 455+0.030, 1.65 roller rockers, Out of Box Eheads 87cc. RPM Edelbrock intake. 3000 stall, TH400, 3.73 12 bolt rear. I could just replace the 292c cam, but wondering what would me more power. I want to stay with a hydraulic cam and the heads are good to .575 lift. Any suggetions?

[tom s]

You should really check out the engine.I lost one lobe and it wiped out the cam bearings and took its toll on the mains and rods also.Good luck.Tom

[Nickv]

I did check the cam bearing. they are good, no copper showing thru and oil pressure was fine. 60lbs cold, 30lbs warm and cruising speed around 55lbs.

[i82much]

Maybe do a couple flushes, put some cheap oil in and drive it really easy for a thousand miles. Drain, fill with cheap oil again, drive another thousand and get a used oil analysis done. If it lasts that long and the oil analysis is good, chances are you are out of the woods.

[screamingchief]

If the valve springs are the ones that came with the Eheads,I'd lose those no matter what cam I was gonna run in it,as I just dont feel those springs are a decent choice,IMO Edelbrock kinda cheaped out on those,and that even might have contributed to the failed lobe(s).

Better springs will also (almost certainly) offer "room" for higher lift cams as well.

Cam options,maybe something like the Crower #60244 (slightly smaller) or the Comp 296AH (slightly bigger) cam ground on a 112° LSA vs. the 108° LSA it normally is ground with would be my choice based on what you were using,and the fact that you say you want to stay with a hydraulic cam & you occasionally use nitrous on this as well.

Whichever one you opt for,ask if they can nitride the cam as well,should help prevent a repeat lobe failure,albeit for a small premium,I know Comp offers that service,and I'm pretty sure Crower does as well.

FWIW

Bret P.

[Nickv]

Thanks for all the information guys. I did another check of the cam I pulled. All the other lobes look fine with a good wear pattern, just the cam lobes for #3 cylinder are rounded. Not sure why those, but I do remember about a year ago I was experiencing some lifter tap and I think I remember pulling the rocker and finding the tip of the pushrod broken off. I think it was #3. The pushrods BTW are Magnum 5/16" 2762's. Don't know if that contributed or not. It's not like this is a recently installed cam. The cam has been in the car for at least 15 yrs. I guess all those street miles and at least over 100 drag strip runs finally took their toll on the cam. I am actually surprised the car ran as well as it did and I was out cruising just last weekend! :-)

[Blued and Painted]

check close for any signs of interference or binding

[BruceWilkie]

Maybe its time for a hydraulic roller?

[Probird]

I would definitely pull that engine out and clean it well. That debris will be throughout the engine. Unless you are wanting an excuse to build a new engine anyway.

[i82much]

Originally Posted by Probird

I would definitely pull that engine out and clean it well. That debris will be throughout the engine. Unless you are wanting an excuse to build a new engine anyway.

I know it sounds crazy because we are all such neat freaks about engine internals, but it really was not that uncommon back in the day to wipe a lobe, install a new cam, and go about your business with no harm. I have personally done it on a sbc, just ran some motor flush through it and got back to beating on it. Same power, same oil pressure, no ill effects.

OTOH, if you have high dollar parts in your engine and want to be really careful, by all means pul it.

[Nickv]

Well, the car is hardly driven at all. Only in the Spring and Summer time. I changed the oil every Spring whether it's driven or not with Castrol GTX 20w50. The inside of the engine is very clean and my oil pressure is still pretty good.
Ca
I doubt I go 500 miles between oil changes on it. The oil is very clean with no glitter when checking it. But like I said I did drag race it on occasion from 2003 till 2007. After that just street miles to cruises. the longest trip I've done in the car was going to the OC cruise in the Spring, 3hrs each way, drive around town and drive home.

I may pull it I haven't decided yet. I may just put in a cam, break it in and go about my business. :-) I may go with a solid cam since the engine at one time had a solid cam in it when it was strickly a drag car before I bought it in 2001.

[screamingchief]

Solid cam,first one that comes to my mind is the Crower #60311 for that sorta combo.

Could also go Comp 290b on a 112° LSA too.

Like before,one slightly smaller,and one slightly bigger.

Wider LSA will be nitrous friendly too.

Use Crower coolface solid lifters,pop extra for Nitriding the cam core too.

And again,if those are the OE valve springs that came on the Eheads,I repeat lose those pronto,I bet $$$ if you check them on RIMAC they wont hold up to muster.

And I'd run a better oil with a flat tappet set-up.

Dont get me wrong,I used to love Castrol GTX too,but IMHO Castrol really has'nt kept up on this segment of their buying public and recent history as far as modern oils & ZDDP and such.

Valvoline VR-1,Brad Penn,Torco,Gibbs,et-al all have flat tappet specific oils.

FWIW

Bret P.

[Dragncar]

I would not even think of using standard Castrol oil with a flat tappet. You need to have real oil or a additive with zinc. Even ol STP oil Treatment has some zinc in it.

[PONTIAC DUDE]

All oils now-days don't have enough zinc to maintain the cam. Castrol is OK ......... as long as you add a ZDDP additive.

Or a hyd roller.

[ChrisTransAm78]

Originally Posted by BruceWilkie

Maybe its time for a hydraulic roller?

Gotta 2nd that. I've never looked back....