Troubleshooting 2 cylinders - Chevelle Tech
Troubleshooting Diagnosing problems done here.

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post #1 of 2 (permalink) Old Oct 7th, 19, 11:11 AM Thread Starter
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Troubleshooting 2 cylinders

I haven't started the engine in awhile because I've been working on suspension and cooling upgrades. Finally got to a state where I could. Previously I did have some rough running issues and per your recommendation I moved the brake vac line to a dedicated port on the intake. And I moved the pcv vac line to the port on the Fitech unit. As I was doing this I noticed the other vac port had a rubber port plug and it was cracked pretty badly, most likely giving me a vac leak. So I replaced that and fired the engine up. It ran OK, but still not great. So I put the IR gun on the headers and each was about 350-400 degrees. But when I put it on 3 and 8, they were only 250 degrees. You can see the specs of my engine in my sig. I did put a roller cam and hydro lifters and pretty sure they're lashed correctly. As i sit here at work, can you help me think of a plan on how to troubleshoot those two cylinders and why they're so cold? I did do a comp test this year and all holes were even..

67 Chevelle 454, M21
Gen IV 454 (out of C30 ), 390 heads 1.88/2.19 valves by Vortecpro, with ISKY Hyd Roller cam (at 050 218 int./228 exh, lift 530 int./552 exh.), RPM performer intake, Fitech 600HP, Dougs headers, and M21, Gear Vendors OD, 3.73's, UMI Suspension, Viking coilovers.
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post #2 of 2 (permalink) Old Oct 7th, 19, 11:44 AM
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Re: Troubleshooting 2 cylinders

Check the porcelain on your plugs for happens. Also double check valve adjustment on those 2 cylinders.

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67 Project SS Clone

Owning a Chevelle project is like having a giant-size piggy bank that you keep pouring money into....but you can't get it back out.
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