Flat Cam: What Now? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

turbohacker · 11-02-2008, 10:08 PM

I have been having a really bad rocker tic for several moths now so i finally blew the motor apart to try and figure it out. The exhaust lifter in the number seven cylinder was at least a sixteenth of an inch shorter than all of the other lifters and it had a doming effect going on. So i pulled the cam and sure enough the same lobe was rounded and shot...

So Now I need a New Cam, What do ya'll recommend?

355ci small block, Muncie m21 four speed, flat top forged pistons 10.5:1, 202 double hump heads with screw in studs and guide plates, not sure on the valve springs, edelbrock performer intake, edelbrock 650 cfm carb. I would like a radical sounding solid lifter cam with some pretty respectable power figures, Mileage isn't a problem...

Thanks!

masterbeavis · 11-02-2008, 10:30 PM

What kind of cam did you have before? I assume you did not like it? Try calling up the two big cam companies, they can make very good recommendations.

dwcsr · 11-02-2008, 10:31 PM

Depends on what you want it to do. If you liked the performance before get the same cam. Most cams are trashed in the first 15 minutes of run time and slowly wear down from there. Use plenty of moly lube on the lobes and lifter bottoms during installation. Or go with a roller kit and not worry about the cam again.

prostreetC-10 · 11-02-2008, 10:57 PM

roller.....roller......roller.........

turbohacker · 11-02-2008, 11:07 PM

I would love to get a roller, but i cannot afford it. The old cam was a cheap rv cam that did ok on the top end but lousy on the bottom, ive herd good things about the Comp Cams XE274, any ideas?

Heavy Evy · 11-02-2008, 11:33 PM

Comp cams's high energy 268 cam. I have it in my 383 stroker and love it!

Bob 68327 · 11-02-2008, 11:35 PM

I put a Isky 292 in mine and Love it My motor is similar to yours but this is a hyd. cam 292 dur. 508 lift way radical sound and good performance . My 2 cents . Bob

turbohacker · 11-03-2008, 12:58 AM

I just looked up the isky and it looks good, do you have a stock valve train? Springs?

Bob 68327 · 11-03-2008, 01:12 AM

No I'm running the springs that isky recommends for the cam don't have the part# off the top of my head but I can get them for you . I'm running Dart heads and 206/160 valves with 200cc intake runners and this cam works awesome . I'm running a 400th and a 3500 stall so it should work well with your 4 speed . I will dig up some part # tomorrow for you if I have time . Bob

Pont406 · 11-03-2008, 01:12 AM

How many miles on that cam? What oil did you run? My local machine shop sees at least 1 a week. Scary.

Bob 68327 · 11-03-2008, 01:24 AM

Oh yeah , Good point pont406 I'm running brad penn oil about 6 bucks a quart but been 1500 miles this summer with no problems . Bob

heavy70 · 11-03-2008, 09:58 AM

XE274H run it you will be very happy with it!!!!

pumpkin · 11-03-2008, 10:06 AM

Big problem with running flat tappet cams is it is very hard to find oil that has the proper additives to lube the cam properly. With tighter emissions on new cars they have removed all the good stuff from the oil. About the only oils left are 20-50 racing oils. As expensive as retrofitting a roller cam into an old engine is, its a whole lot cheaper the wiping out the whole engine. All that metal that came of the cam, has now gone through the engine and started to grind bearings and crankshaft away.

whatnow123 · 11-03-2008, 10:50 AM

Quote:

Originally Posted by pumpkin

Big problem with running flat tappet cams is it is very hard to find oil that has the proper additives to lube the cam properly. With tighter emissions on new cars they have removed all the good stuff from the oil. About the only oils left are 20-50 racing oils.

You should use Mobil 15W 50 extended life as it still has the "good stuff" in it still. I use it in mine and have had no problems at all.

My engine is similar to yours, I'm running a Voodoo cam and think it's awesome. It's split pattern, 480/490 lift, or around that.

turbohacker · 11-04-2008, 01:43 AM

I ran rotella t because it still has some zinc in it and its good for breaking in a cam. The cam i had only had about 500 miles on it...

I talked to my local engine builder and ordered a comp cams 262, don't remember the lift, he recommended it because it still has some torque but has a really lopey idle.

Thanks for the help though!

*chevy29267truck* · 11-04-2008, 02:17 AM

call up northern auto parts at 18008310884 they are in iowa
i get a lot parts and other stuffel from them

Rollie396 · 11-04-2008, 03:59 AM

I just went through a similar situation,but my cam had 2 lobes/lifters that looked like that.
I got nervous about all that metal going through the engine (there was a big chunk of metal stuck in the dizzy gear when I pulled it

)so I flipped it over and pulled a main cap....the crank now has freshly ground mains and rod journals(-.010) with new bearings throughout (cam too)and rings with a fresh hone.
When I rebuilt this time I use AC Delco EOS (pt#992869) along with all the lube supplied with the cam and lifters.I followed "proper" break in procedure and things are good.
Might be a good idea to check things out if you haven't already done so.

Super73 · 11-05-2008, 01:37 PM

You can order cams that go through an extra hardening process. Being I'm a roller guy, I don't have first hand experience, but have heard that it really helps the longevity of a flat tappet cam.

bigfredtn · 11-13-2008, 12:07 PM

I run the extreme energy in my truck. I run the XE-294 in my small block. It makes good power, but its very noisy.

11-02-2008, 10:08 PM	#1
turbohacker PISS POOR Join Date: Dec 2007 Location: visalia, ca Posts: 98	Flat Cam: What Now? I have been having a really bad rocker tic for several moths now so i finally blew the motor apart to try and figure it out. The exhaust lifter in the number seven cylinder was at least a sixteenth of an inch shorter than all of the other lifters and it had a doming effect going on. So i pulled the cam and sure enough the same lobe was rounded and shot... So Now I need a New Cam, What do ya'll recommend? 355ci small block, Muncie m21 four speed, flat top forged pistons 10.5:1, 202 double hump heads with screw in studs and guide plates, not sure on the valve springs, edelbrock performer intake, edelbrock 650 cfm carb. I would like a radical sounding solid lifter cam with some pretty respectable power figures, Mileage isn't a problem... Thanks! __________________ Slammed 67 long bed with vette suspention build thread http://67-72chevytrucks.com/vboard/s...d.php?t=291149 Last edited by turbohacker; 11-02-2008 at 10:25 PM.

11-02-2008, 10:30 PM	#2
masterbeavis Having issues Join Date: Jul 2005 Location: Eldorado Ca, an hour east of sacramento Posts: 696	Re: Flat Cam: What Now? What kind of cam did you have before? I assume you did not like it? Try calling up the two big cam companies, they can make very good recommendations. __________________ Quando Omni Flunkus Moritati. The Man's Prayer: "I'm a man, but I can change, if I have to, I guess."

11-02-2008, 10:31 PM	#3
dwcsr Hollister Road Co. Join Date: Apr 2005 Location: Houston Posts: 6,131	Re: Flat Cam: What Now? Depends on what you want it to do. If you liked the performance before get the same cam. Most cams are trashed in the first 15 minutes of run time and slowly wear down from there. Use plenty of moly lube on the lobes and lifter bottoms during installation. Or go with a roller kit and not worry about the cam again.

11-02-2008, 10:57 PM	#4
prostreetC-10 My Carbon Footprint Join Date: Oct 2008 Location: Orygun Posts: 5,527	Re: Flat Cam: What Now? roller.....roller......roller......... __________________ A quick "pedalfest" *Still getting loose (carb test)* 496 Initial fire up video!

11-02-2008, 11:07 PM	#5
turbohacker PISS POOR Join Date: Dec 2007 Location: visalia, ca Posts: 98	Re: Flat Cam: What Now? I would love to get a roller, but i cannot afford it. The old cam was a cheap rv cam that did ok on the top end but lousy on the bottom, ive herd good things about the Comp Cams XE274, any ideas? __________________ Slammed 67 long bed with vette suspention build thread http://67-72chevytrucks.com/vboard/s...d.php?t=291149

11-02-2008, 11:33 PM	#6
Heavy Evy born to lose Join Date: Sep 2008 Location: Salt Lake City, Utah Posts: 842	Re: Flat Cam: What Now? Comp cams's high energy 268 cam. I have it in my 383 stroker and love it! __________________ _____________________ '67 Chevy Belair Wagon 283 Powerglide '68 Chevy II Nova 2 door 350 TH400 Sold!! '71 Chevy C20 350 TH350 '71 Chevy C10 Burb 350 TH350 stolen totalled gone.... Burb Build http://67-72chevytrucks.com/vboard/s...d.php?t=475155 Nova Build http://67-72chevytrucks.com/vboard/s...d.php?t=498979 Wagon Build http://67-72chevytrucks.com/vboard/s...d.php?t=543052 Not giving a truck.

11-02-2008, 11:35 PM	#7
Bob 68327 72 Chevelle Club Join Date: Jun 2007 Location: Newton , Iowa Posts: 2,052	Re: Flat Cam: What Now? I put a Isky 292 in mine and Love it My motor is similar to yours but this is a hyd. cam 292 dur. 508 lift way radical sound and good performance . My 2 cents . Bob __________________ I Have The Right To Remain Silent,But Lack The Ability 1972 Chevelle ... Mine 2006 Trailblazer... Hers 2002 Buick century ... Kids 2002 K1500 Z-71 EXT CAB ... Daily Driver 2005 Rockwood Roo ... For Camping 1974 Harley-Davidson XLH Sportster 84'' stroker

11-03-2008, 12:58 AM	#8
turbohacker PISS POOR Join Date: Dec 2007 Location: visalia, ca Posts: 98	Re: Flat Cam: What Now? I just looked up the isky and it looks good, do you have a stock valve train? Springs? __________________ Slammed 67 long bed with vette suspention build thread http://67-72chevytrucks.com/vboard/s...d.php?t=291149

11-03-2008, 01:12 AM	#9
Bob 68327 72 Chevelle Club Join Date: Jun 2007 Location: Newton , Iowa Posts: 2,052	Re: Flat Cam: What Now? No I'm running the springs that isky recommends for the cam don't have the part# off the top of my head but I can get them for you . I'm running Dart heads and 206/160 valves with 200cc intake runners and this cam works awesome . I'm running a 400th and a 3500 stall so it should work well with your 4 speed . I will dig up some part # tomorrow for you if I have time . Bob __________________ I Have The Right To Remain Silent,But Lack The Ability 1972 Chevelle ... Mine 2006 Trailblazer... Hers 2002 Buick century ... Kids 2002 K1500 Z-71 EXT CAB ... Daily Driver 2005 Rockwood Roo ... For Camping 1974 Harley-Davidson XLH Sportster 84'' stroker

11-03-2008, 01:12 AM	#10
Pont406 Registered User Join Date: Aug 2007 Location: West Hills, California Posts: 679	Re: Flat Cam: What Now? How many miles on that cam? What oil did you run? My local machine shop sees at least 1 a week. Scary.

11-03-2008, 01:24 AM	#11
Bob 68327 72 Chevelle Club Join Date: Jun 2007 Location: Newton , Iowa Posts: 2,052	Re: Flat Cam: What Now? Oh yeah , Good point pont406 I'm running brad penn oil about 6 bucks a quart but been 1500 miles this summer with no problems . Bob __________________ I Have The Right To Remain Silent,But Lack The Ability 1972 Chevelle ... Mine 2006 Trailblazer... Hers 2002 Buick century ... Kids 2002 K1500 Z-71 EXT CAB ... Daily Driver 2005 Rockwood Roo ... For Camping 1974 Harley-Davidson XLH Sportster 84'' stroker

11-03-2008, 09:58 AM	#12
heavy70 Registered User Join Date: Dec 2007 Location: choctaw, oklahoma Posts: 100	Re: Flat Cam: What Now? XE274H run it you will be very happy with it!!!!

11-03-2008, 10:06 AM	#13
pumpkin Registered User Join Date: Apr 2006 Location: East Sooke B.C. Canada Posts: 543	Re: Flat Cam: What Now? Big problem with running flat tappet cams is it is very hard to find oil that has the proper additives to lube the cam properly. With tighter emissions on new cars they have removed all the good stuff from the oil. About the only oils left are 20-50 racing oils. As expensive as retrofitting a roller cam into an old engine is, its a whole lot cheaper the wiping out the whole engine. All that metal that came of the cam, has now gone through the engine and started to grind bearings and crankshaft away.

11-04-2008, 01:43 AM	#15
turbohacker PISS POOR Join Date: Dec 2007 Location: visalia, ca Posts: 98	Re: Flat Cam: What Now? I ran rotella t because it still has some zinc in it and its good for breaking in a cam. The cam i had only had about 500 miles on it... I talked to my local engine builder and ordered a comp cams 262, don't remember the lift, he recommended it because it still has some torque but has a really lopey idle. Thanks for the help though! __________________ Slammed 67 long bed with vette suspention build thread http://67-72chevytrucks.com/vboard/s...d.php?t=291149

11-04-2008, 02:17 AM	#16
chevy29267truck Account Suspended Join Date: Sep 2008 Location: Alva Florida Posts: 668	Re: Flat Cam: What Now? call up northern auto parts at 18008310884 they are in iowa i get a lot parts and other stuffel from them



Register or Log In To remove these advertisements.

11-04-2008, 03:59 AM	#17
Rollie396 someday it will be done! Join Date: Sep 2004 Location: Lloydminster,AB. Canada Posts: 1,620	Re: Flat Cam: What Now? I just went through a similar situation,but my cam had 2 lobes/lifters that looked like that. I got nervous about all that metal going through the engine (there was a big chunk of metal stuck in the dizzy gear when I pulled it)so I flipped it over and pulled a main cap....the crank now has freshly ground mains and rod journals(-.010) with new bearings throughout (cam too)and rings with a fresh hone. When I rebuilt this time I use AC Delco EOS (pt#992869) along with all the lube supplied with the cam and lifters.I followed "proper" break in procedure and things are good. Might be a good idea to check things out if you haven't already done so. __________________ '72 C-10 Proud owner of a million new and used pieces that used to be and will once again be(god willing) a testament to the term "they don't build em like that anymore. '80 LWB 2wd beater '67 GMC long fleet (cab donor) '66 long step (parked till it's turn comes around) '65 short step (parts truck that will donate it's bed and possibly frame to the '66) '06 Grand Prix wife's car (she hardly lets me touch it) my pics

11-05-2008, 01:37 PM	#18
Super73 Registered User Join Date: Nov 2007 Location: Bay Area, Ca Posts: 2,841	Re: Flat Cam: What Now? You can order cams that go through an extra hardening process. Being I'm a roller guy, I don't have first hand experience, but have heard that it really helps the longevity of a flat tappet cam. __________________ ------Motor---------------Bottle 60'---1.53---------------1.41 1/8---6.58 @ 105.92----5.87 @ 118.41 1/4---10.38 @ 126.97----9.24 @ 142.49

11-13-2008, 12:07 PM	#19
bigfredtn Active Member Join Date: Dec 2002 Location: West TN (Memphis area) now. East TN (my favorite place to live). Posts: 157	Re: Flat Cam: What Now? I run the extreme energy in my truck. I run the XE-294 in my small block. It makes good power, but its very noisy. __________________ BigFredTN 70 chevy stepside 350 with some goodies inside, turbo 400. 69 Chevy long wheel base. Dad bought new in 1970 62 Chevy Impala 98 GMC Yukon 1970 Ford Mustang Fastback I know its a Ford.

Register or Log In To remove these advertisements.