[HotRodF100]

I have a Mallory dual point and from the sounds of the engine, pinging on a hard pull, it or the timing isn't quite right. It's a 350 Chevy and I set the timing for 8 deg but I haven't checked total timing. The guy who built the motor said he just set it up just to get it running. I think that he meant that I have to tweak it. I'm from the old school, give me a feeler gauge, timing light, and a dwell meter and I'm right at home. I'm looking for some advice before I rip into it. Thanks!

[ February 16, 2002: Message edited by: HotRodF100 ]

[ February 16, 2002: Message edited by: HotRodF100 ]</p>

 

[Roy Newton- exprotech]

I think the first thing you need to do is to put a timing tape on the front engine pulley.You need to know what the total timing is and go from
there. ROY

[ February 16, 2002: Message edited by: Roy Newton- exprotech ]</p>

 

[dmorris1200]

just a quick reminder, checking timing should only be done after you checked dwell settings for both sets of points, I usually put a small piece of matchbook cover in one set of points (the same way you'd insert a feeler gauge)to dissable them. You can now check dwell for the other set of points. Then disable the set you just set with the piece of matchbook cover run the engine and check your dwell for the second set. I'm not sure about your specific application but my individual points are set to approx. 26 deg. each, and with both points firing dwell is approx. 33 deg. After your sure both points are set to specs than you can go into setting up the timing. Also if the motors pinging check to make sure she's not running lean (high combustion temps), faulty EGR system, carb tuning, etc. good luck.

 

[HotRodF100]

Maybe more details would help. The motor is a 350 out of a '77 Monte Carlo. It's pretty much stock and was rebuilt 3300 miles ago. When I bought the truck, the timing was beyond the marks. When I started it hot, I could tell that it was too high by the way that it turned over. I dropped it back to 8 degrees but I noticed a noticable drop in power from the engine. When the engine is cold and I pull out of the garage it sounds like it has a slight knock. If I pull off the vacuum advance, it doesn't knock. Once it warms up and with the vacuum advance hooked up, there is no knock. Sometimes I notice a ping on a hard pull up a hill but it's real hard to hear because of the headers and flow mufflers, it may be pinging other times and I can't hear it. These old '53 F-100s weren't known for their quiet ride. The Mallory cap doesn't have an adjustment door like i'm used to in the old days. I guess its poke and hope until you get it right, adjust, put it together, run it, check it, do it again. So if I understand this right, you adjust each set of points like the other one isn't there (because the other is disabled), each set of points get adjusted the same, and your settings are only as good as the worst point adjustment that you have? So basically it's like a single point distributor with 2 sets of points running in parallel??

 

[dmorris1200]

your getting the jist of it. It's time consuming but you must get both points set correctly, and every time you change the dwell you just changed your base timing. That's why dwell gets set first. Not to familiar with the 77 Monty but if that motor was set up originally with an EGR system and you eliminate it you must re-tune the carb if still using original carb. Could be many things, can only guess at things without seeing car. Good-luck again.

 

[HotRodF100]

There's no EGR and it has a Edelbrock 550 CFM square bore carb on it. All in all it runs pretty good other than the pinging. This is one of those GM warehoused blocks that was cast in 1974 but not used until 1977. You know how it is with us rodders/tinkerers, you always want to get a little more out of it no matter what it is, and since it only get driven once in a while we have the time to mess with it. I appreciate the help, I also found a website called centuryperformance.com that spells out the setup of the Mallory distributor. It runs now, hope it does when I "fix it"!

 

[Henry Highrise]

Looks like you have got it figured out. We used those Mallory dual points all the time when I was in High School, thats been 39 years ago. I had not thought about them in years untill I read your post. Some of the Chrysler vehicles came stock with dual point distributers about that time.

 

[Jooooooe]

I had a Mallory dual point years ago and I remember that it came with a dwell key for setting the dwell. It's been so long I can't remember the details, but it simplified the operation. It was a plastic stick that had step notches in it and each notch indicated a higher or lower setting.

 

[gearhead]

Do you know what the heads are from? for example, if it has 305 heads on a 350, you will get a big jump in compression and you will need to run higher octane gas. What have you been using for gas? Personnally, I would ditch the dual point, as you are finding out they are something of a hassle and you don't really need it on a basically stock engine. A stock single point or factory HEI would be a much better/simpler way to go. If you want the look of the smaller point dist., Pertronix makes a good drop-in HEI setup for the factory poit dist. for about $80.

 

[Jooooooe]

How many times does it have to be said, 305 heads do not work on anything but 305's and all other small block heads do not work on 305's.

 

[gearhead]

So Joe, just what exactly are you refering to in that they won't work? Saying something does or doesn't work without giving a reason doesn't help anybody. Yes, you can't put large valve 350 heads on a 305 because they will hit the block because of the small bore of the 305, but 305 heads will physically work on a 350, I have seen it done. I'm talking "classic" heads, not center bolt stuff.

 

[dmorris1200]

Hey HotRodF100, just wondering how the distributor situation is coming along. Have you found the fix yet?