mallory hyfire VI problem
 

Took out msd 6a and installed #685 mallory box. Now tach (3905 autometer) bounces and doesnt read properly. 2 calls to mallory tech with little help. One said had to have their coil and tach adapter(what a surprise), other said shouldnt need them. One tech said to hook to negative side of coil directly (instead of tach output on box) but autometer says not to. coil is 8202 msd blaster 2. distributor is stock gm breaker point. Any ideas or suggestions appreciated. Thanks, Ron

Re: mallory hyfire VI problem
 

Don't think that coil is compatible with that box.
Chip

Re: mallory hyfire VI problem
 

Thanks, guys. Primary ohms resistance is .7 on msd coil and .6 on "recommended" Mallory coil, so I don't think that is the issue. Will check cap as suggested and try another set of wires also. Tach worked fine with MSD last week. Is the Mallory that much more "powerful" than the MSD? Also, per Mallory instructions "do not ground to engine block, ground to frame or chassis". MSD says ground to negative terminal of battery or engine block. Thanks, Ron.

Re: mallory hyfire VI problem
 

He's right, coil is not right for the box. Get mallory's coil, and all will be fine. We have ran one for seven years.

Re: mallory hyfire VI problem
 

I fought this problem with the same box. Mallory insisted there was something in the car causing it. After I made them send me a replacement, the problem went away.

Re: mallory hyfire VI problem
 

Thanks, guys for suggestions. Tried all, and then some, no difference. It is going back to Mallory. FYI, Mallory tech line is a joke. Sam at centuryperformance is the person to go to on Mallory tech problems. Ron.

Re: mallory hyfire VI problem
 

I had a similar problem. We have Hyfire 6 boxes in both our cars. I bought one in 2006 at Maple Grove and had zero problems with it in 5 years. We had our Crane box go bad in the other car and replaced it with a Hyfire 6. Third time was a charm. I had to send back two boxes that were bad. It may be possible that Mallory had a bad run of boxes. The last one they sent me works fine. It was needless to say a long season dealing with bad electronics.

Ryan