valve clatter

[331stroker]

I have a 331 stroker with a holly systemmax 2 ,longtub headers ,accell ignition, 30lb injectors,190gpa fuel pump,fulthan urthan syspension, holly fuel pressure regulator, forged crank, h-beam rods,arp bolts,upgraded centerforce dual-friction kevlar button clutch. Stock ecu and programming
Here is my problems 1. I have a air/fuel mix guage which I know are inaccurate. At Idle or if I hold the gas at a certain rpm it idles up and down about 200 rpm and back up fluxuating at the same the rpms drop i run lean.
problem 2. I have valve clatter up to 2000 rpm unless I accerate heavly. I have about 80 psi oil pressure any info is great

[goodyear1984]

for your lean condition...the a/f gauges are only accurate with a wide band o2 sensor .....you prolly need to set the valve lash..

[USMC302]

1. As goodyear stated, a wideband will be more accurate than an off the shelf air/fuel meter. What are the readings your getting from your current one? What is your FP set at?
2. You didn't mention heads or an aftermarket valve train so I'm assuming it's stock and non-adjustable still. If you changed valve covers, some are a little thinner and allow more noise to come through, on the other hand, be sure all rockers are tight and get a mechanical oil pressure gauge to really see what your oil pressure is doing throughout the RPM range.
3. Last but not least, you mentioned 30lb injectors but with stock ECU and programming. Are you a speed density or Mass Air car, you never mentioned the year, If mass air car, did you get the meter calibrated for the injectors?

[331stroker]

Ok my car is a 1990 stang. It is mass air and the fuel pressure is set at about 44psi. Some time a/f will not even register at low rpms about 3500 and up it runs semi rich. Yes they are aftermarket sheet metal valve covers . I have the Ford Racing 1.6 blue roller rockers. I nomaly have 80-90psi of oil through the whole range but at idle is were you see 75-80 psi. I have a C&L 76mm mass air meter and it has been calibrated to the 30lb injectors . As for the heads the Holly SyS max2 comes with 61cc heads, and intake, the cam 221/223 duration at .050, .509/.509 in lift with 107 deg lob separtion, hardened pushrods

[USMC302]

Awesome, ok, the air/fuel ratio is at exactly what? It's normal to jump around at idle, the computer tries to achieve a 14.7 mix, you need a real air/fuel meter to really tell how lean or rich it's running. The sheetmetal valve covers will def let tons of valve chatter out, but it's still safe to go ahead and be sure the valve lash is set, if you take the valve covers off, make sure none of the roller rockers are loose enough that you can lift one off the valve, side to side movement is ok, just not up and down. Most of the time they will need to be re adjusted after the first few hundred miles or so anyway. The oil pressure will generally be lower at idle and higher though the rpm range, nothing out of the ordinary there. Your fuel pressure sounds extremely high for 30lb injectors N/A. You should try bringing it down to around 35-38 for a test run at the track, don't pay attention to ET, look at MPH, take away fuel until you slow down.