Recommendations for a filter to get the tach working.

[MAC71Cheyenne]

Yes, no, not needed, needed, ??? Older posts and searches are like a blindfolded drunk driver.
71 C10 wV8. New Summit HEI dist and ignition box. Tach doesn't work properly, runs negative..or positive but never hits 1000 rpm. Disconnected the wire to the cap, (no inline GM filter) so it does not burn up. Obviously I would like to have the dang thing functioning properly.
Thoughts and recommendations....

[Andy4639]

Originally Posted by MAC71Cheyenne

Yes, no, not needed, needed, ??? Older posts and searches are like a blindfolded drunk driver.
71 C10 wV8. New Summit HEI dist and ignition box. Tach doesn't work properly, runs negative..or positive but never hits 1000 rpm. Disconnected the wire to the cap, (no inline GM filter) so it does not burn up. Obviously I would like to have the dang thing functioning properly.
Thoughts and recommendations....

I have never run a ignition box so I can't really help you out. Only thing I can suggest is call summit and ask them about it.
This last tach I just installed in my 67 ramp truck I did use a 5amp fuse on the hot wire going to the fuse block though. No filter going to the coil though.

[MAC71Cheyenne]

Been following your progress..👍
Have to double check but I think I put in a fuse like you did, 3 amp. I'll call them Monday and see what they have to say. Tried going off the neg at the cap instead of the tach output but it made no difference. Disconnected it for now since I would be really unhappy to fry the board or tach, even with a fuse.
Thanks!

[MAC71Cheyenne]

After though...PO had swapped out intake and carb for Edelbrock units, headers, and MSD ignition tied into a modified stock dist. The ADD in me says to remove all that and go with a stock intake and exhaust manifolds with GM hei dist. He was more hot rodder n I prefer basic GM with the shields and heat risor without burning up plug wires....just haven't figured out the +n- of doing that...and the cost.

[Andy4639]

The tach goes to the tach connection not the - of the coil. The HEI caps are mark battery & tach. Mine is been running fine since the new one arrived with the 5 amp fuse.

[Dead Parrot]

2nd on the stock HEI having a Tach connector. If a call to Summit doesn't reveal a good tach connection on the MSD unit, easy solution might be replace distributor with a good OEM HEI unit. For a stock or near stock motor, they have plenty of juice.

If the intake is one of the Performer or Performer RPM versions, they are a nice upgrade over stock and rarely cause any compatibility issues.

Most folks block off the crossover ports on the intakes when doing the swap. If yours is a daily driver, might consider a new set of intake gaskets if you do a dizzy swap and leave the crossover ports open. A little heat in the intake usually helps a daily driver, especially for colder climates, but make sure you have a good insulating spacer for the carb. The intake likes the heat but the carb really doesn't.

Headers are a mixed bag for a daily driver. Ceramic coated ones avoid most of the burnt plug wire problems but cost more. I have read a few threads on this forum that say the vortec exhaust manifolds flow well for stock daily driver applications.

[MAC71Cheyenne]

Thanks for the info.
About time I convert the garage from house projects to truck projects again.