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Pro Tips (cont.)

Tech Tips 1 Tech Tips 2   Tech Tips 3   Tech Tips Index




Installation of Steel Bolts into Aluminum Parts


For any applications of steel bolts/studs into aluminum parts {cylinder heads, valve covers, etc.}, ALWAYS use some form of anti-seize compound on the threads. Further, it's best to use a bottom tap to "chase" the threads in aluminum parts and clean bolt threads before applying the compound. And if any factory-recommended torque settings are provided, adhere to them strictly. This may seem to be a suggestion of small importance, but only one experience installing Heli-coils in hard-to-reach places will underscore the benefits of anti-seize



Driveability Problems with ECM-equipped Cars
Especially with import vehicles, the electronic control module {on-board computer} is installed beneath the front seat. According to the PMAG, soft-drinks and coffee spilled on front seats finds its way into the ECM, resulting in sporadic {or permanent} driveability problems that are particularly difficult to diagnose…unless the spill is identified. Complete ECM replacement is considerably more expensive than the drink that may have caused the problem. Exercise caution because it’s not an infrequent problem.



Identifying Cylinder Mis-fire on Racing Engines
Especially on engines equipped with headers, a couple of methods are handy to remember. With the engine idling, “dab” the headers with a wet rag, just beyond the header flange. If the moisture doesn’t disappear immediately, the mis-fire is found. Also, small holes {about 1/8-inch o.d.} drilled near the header flange allows you to see combustion flame, through the hole, if the cylinder is properly firing….ala Smokey Yunick of days gone by. You can also hook a timing light to each individual plug wire {one at a time} to see if firing voltage is present. Or, you could do all three!



Camshaft Break-in
The importance of this cannot be over-emphasized! Before starting a freshly-cammed engine, make certain initial ignition spark timing is correct by whatever method you wish. One such approach is to “starter-bump” the engine until crank damper timing marks align to the initial timing setting desired {a few degrees BTDC}. Position the distributor housing to align the rotor tip with the #1 spark plug wire terminal. Fill the cooling system. Make sure the induction system {carburetor, TBI, fuel pressure, etc.} is set for starting the engine. Once the engine fires, quickly adjust engine speed to about 2000 rpm {or whatever is recommended by the cam manufacturer} and continue running the engine for a minimum of 15 minutes. During this time, don’t allow the engine to idle. This procedure is recommended for any type valve lifter or camshaft location.



Plug Wires
Don't bundle spark plug wires together with tie straps. This can cause misfire because of leaking voltage between wires. On Chevy V-8 engines, when #5 fires , leaking voltage can cause #7 to fire 90 degrees too early resulting in damaged parts.



Warm Up Engine
Always warm up engine before racing to a miniumum of 160 degrees oil temp. Cool oil will show high pressure but won't be flowing through bearings. Results are damaged bearings and valve springs.



Jetting Alcohol Engines
When jetting alcohol engines, start with what you know is rich. You'll hear a miss or misfire in upper RPM range, or you'll feel engine leveling off. At this point, reduce jetting by trial and error until motor is crisp. Jetting by engine temp alone is very dangerous because if you have efficient cooling system, you can burn motor or send it into detonation while water temp shows cold.


Adjustable Timing Lights
When setting timing with adjustable timing lights, be sure if you're setting at 34 degrees on the back of the timing light that you are using TDC on the damper. We've had customers that have used 34 degrees on timing light and damper--results are burnt pistons and/or blown up motors. Always check timing after a motor is warm at the highest RPM your motor will see.



Adjusting Valves with Perma-Locks
When adjusting valves with perma-lock adjusters, after reaching desired valve lash, loosen adjuster 1/4 turn, tighten allen set screw, force lock adjuster tight (within reason) to desired lash. This will prevent lash adjuster from coming loose.


Valves with Stud Girdles
When adjusting valves with stud girdles, after tightening stud girdles you must recheck valve lash.

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