I have made several posts on here about this problem my car has been having. The car has a rough idle, seems to chugg throughout the operating range, worse when I go up hills, it also lacks power and is throwing no codes. Also, under full load, there is a popping or knocking or some sound comming from the engine? My ignition is all good as well. I have been told to check my O2 sensor, gut my cat and also maybe the head gaskets. I have the engine appart now to install a new cam, and thought is there any chance it could be blown head gaskets, cuz if so I'd like to replace them now while the engine is appart.

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End

Current Mods: LT4 Hot Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Gutted Catalytic Converter, Performance Resource Chip, Accel Ignition Coil, Cap, Rotor, 8.8mm Wires, K&N Filters, JET TPI Air Foil, Ported TPI Plenum and Base, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

7.5" 10 Bolt with 3.42s soon to come!

 

Dan,
I don't know if this will help you but this is my story. I had the original engine, 5.7 L, with about 95,000 miles on it and my idle started to get, very little, rough sounding but you had to loisten real hard. But that was the only thing a few months later it sounded like I had a cam in it, but I didn't. Then one day coming home from work on the PA Turnpike I lost power in OD! I down shifted to D and it was okay but if I tried WOT the car wouldn't accerlerate much but the engine rev'ed. I checked everthing O2, Timing, injectors,etc, etc ... . And the tranny and converter were just replaced like 5,000 miles so I new they were good.
I started to check the compression and found out that the 2 middle cylinders on each side had about 50 - 70 psi and the 4 conner ones had >150psi !
When I got then off some how the head gasket blew out between these 2 cylinders. Weird I know.
Like I said this happen to me but I can't tell you this is your problem but it was mine. I know how fustrated this can be.

Best Of Luck!

 

My money is on the head gasket being blown between 2 cylinders. It happens quite often, probably more often than one blows between coolant and a cylinder.

Did you do a compression test? That tells the tale, unmistakably.

I think it would be wise regardless to pop the heads off; if you haven't found the problem yet, then whatever it is, it's still there, and you're going to put it all back together and still have it if you don't find it.

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"So many Mustangs, so little time..."
ICON Motorsports

 

Dan,

I'll agree with RB. As long as the intake is off and you are about 17 bolts on each side away from removing the heads, why not do it? At the very least, you can clean the excess carbon, inspect and mic the bores, install new gaskets, and inspect the valves closely. You might even want to freshen the valves and seat, or go all-out and install larger valves to compliment the new cam. The coolant is already drained (or should be) and there is not much left to removing the heads. It would also be a good opportunity to match the ports to the intake and exhaust manifolds, and possibly do some deep porting if the grinder "gets away" from you.

At the very least, spend the fifty bucks for gaskets and pull the heads for peace of mind.

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Later,
Vader
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"I'm gonna talk about some freaky sheet now..."
Adobe Acrobat Reader 4.0
KaleCo Auto Parts

 

If you do remove your heads, check the combustion chamber areas very closely for hairline cracks, especially around the exhaust valve seat. The other thing you want to do is use a machinist's straight edge, or equivalent and a feeler gauge and check to make sure the surface of the head is level. If it varies more than about two thousandths, then you need to have the heads milled. Today's composition head gaskets will usually seal any variances under two thousandths, but more than that will usually cause a head gasket to leak. If you use steel shim head gaskets like the factory did, you have to have the head surfaces almost perfectly level to assure a good seal.

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89RS w/350 TPI; 69RS/SS w/450 HP 350/Muncie 4-Speed "Too weird to live, too rare to die."

 

Is there anything special I have to know about pulling the heads?

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End

Current Mods: LT4 Hot Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Gutted Catalytic Converter, Performance Resource Chip, Accel Ignition Coil, Cap, Rotor, 8.8mm Wires, K&N Filters, JET TPI Air Foil, Ported TPI Plenum and Base, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

7.5" 10 Bolt with 3.42s soon to come!