Title: | Musclecars |
Notice: | Noter Registration - Note 5 |
Moderator: | KDX200::COOPER |
Created: | Mon Mar 11 1991 |
Last Modified: | Mon Jun 02 1997 |
Last Successful Update: | Fri Jun 06 1997 |
Number of topics: | 182 |
Total number of notes: | 5467 |
I have a 1985 GMC Cabalero (ElCamino) that had a 4.3 V6 in it. I installed a 305 IROC engine and connected the factory tach. wire to the new distributor. The tach is reading too high. Is there something I can do externally to the tach wiring to correct the calibration? Add an in-line resistor? The wire on the firewall for the tach has what appears to be a condensor in line with it. Is there a different one maybe for a V8 that I can change to correct the problem? John
T.R | Title | User | Personal Name | Date | Lines |
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155.1 | not a resistor..... | CSC32::J_KALINOWSKI | Forget NAM?....NEVER! | Tue Jan 31 1995 10:29 | 6 |
You need to modify the amount of *pulses* going to the tach.... you had 6, now you got 8. See? All GM tachs have settable jumpers to match what engine you have. -john | |||||
155.2 | How are you at tack removal ? | TROOA::SCHERF | Tue Jan 31 1995 10:33 | 10 | |
MOST OF THE GM TACH'S I'VE SEEN MUST BE REMOVED TO FIX THIS. ON THE BACK, THE PRINTED CIRCUIT BOARD HAS A SMALL FUSE OR DIODE SOLDIERED ACROSS TO POINTS. YOU SHOULD SEE SEVERAL POSITIONS MARKED 4,6,8. YOU NEED TO MOVE THIS TO THE 8 POSITION. THE TACK WORKS ON THE ASUMPTION THAT THE HEI DISTRIBUTOR WIL PRODUCE X AMOUNT OF PULSES in revolution ie 6 for the 4.3. you are now producing 8 in one revolusion so it thinks the motor is turning a higher rpm than it truly is. Jeff Scherf | |||||
155.3 | HOTLNE::MALESKY | Tue Jan 31 1995 11:08 | 6 | ||
.1,.2 Thanks. I'll remove it this weekend and see what the pc board reveals... John |