100 studder at high rpm, when warm???

[Eric_P]

My '56 BN2, once warm, gets this studdering, miss-like, hesitation at highway speeds. I can back off the trottle and it'll run normal when speeds get down around 50-55 but any faster it starts again. The first time it happens I was SURE I was out of gas. That wasn't the case. I was suspicious it was a fuel delivery problem but I'm starting to wonder about ignition and the distributor. It only happens when the car warms up good (I can run 70mph for a short while when I first start the car up).

Any experiences suggestions? I'm not sure which direction to go first.

Thanks in advance!

 

[Keoke]

I would first check the sparkplug gap and if correct reduce it about 0.001". Fwiw---Keoke

 

[nevets]

my guess is it's ignition related...yes check the plug gap (close by 0.001" - wow that's less than the thickness of a human hair), but also points, wires, etc.

 

[Ed_K]

That sounds a lot like a old coil that has gone bad.

 

[Eric_P]

Very good. Those things should be replaced and/or inspected anyway.

This problem made me look around a little. Anyone ever use the Mallory dist. that is available for these cars. Good? Worthwhile swap?

 

[Michael Oritt]

Eric--

I recently replaced the distributor in my wife's 3000 when I determined that the high-speed miss was related to shaft wobble. I used a Mallory Unlite. Go to the Century Performance website at:

https://www.centuryperformance.com/detail.asp?product_id=MAL-4767801

I also went for the Mallory coil and ignition wires--see attached photo.

 

[Eric_P]

I'm thinking for reliability (and since this will be a part-time race car) I might just go the Mallory route from the get go. The site doesn't specifically list the 100/4 though. How do I figure out which 4cyl model to use? What style trigger?

See list: https://www.centuryperformance.com/mallory/dizzymatrix8.asp

 

[Michael Oritt]

Eric--

It's the same as for the TR7. Go to:

https://www.centuryperformance.com/detail.asp?product_id=MAL-4571301

You can get Mallory distributors in either vacuum or non-vacuum advance and with either optical or magnetic trigger--Unilite or Maglite) or of course dual points. I have the Unilite w/vacuum advance on my 100--see the attached photo which shows a bit of the unit.

 

[anthony7777]

gents, while we are on the subject of ignition,several months ago someone here posted a part # for a napa generic set of replacement plug wires made with copper wire not the fiberglass/silicon jobs for a.h. 3000, my local napa dist. tells me they dont sell this set, and i cant locate the info on the search feature, anyone know the correct part # thanks, a7777. /ubbthreads/images/graemlins/savewave.gif

 

[Eric_P]

What am I doing wrong, I can't open photo attachments!?! Says "error"

 

[Eric_P]

Pros and Cons of vac vs. non-vac advance? Optical trigger?

 

[Ed_K]

That was me. I'll check my notebook and then edit this post in a few minutes...
... Napa 700173 stranded wire 7mm 6cyl semi-custom made by Belden.
.... I did a search and found that they still have them ! Notice the price !
https://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=430&PartNum=700173
/ubbthreads/images/graemlins/cheers.gif

 

[Ed_K]

IMHO The rotating magnets that trigger a hall effect transistor is the best design because there are a few less points of failure than the various optical sensor
types.

 

[Keoke]

WOT!,U mean Napa does not sell ignition wire sets that are composed of stranded copper wire??. Since you need only one fitted end any "V8" 7mm set can be used just cut to fit and you are good to go. OTOH, if you really want a good set of wires go to a performance shop and buy Mallory wires for an American V8 too.Enough wire using this method to do two Healeys.--Keoke- /ubbthreads/images/graemlins/driving.gif

 

[Ed_K]

Bout the same price as dem doggy collars !
/ubbthreads/images/graemlins/jester.gif

 

[anthony7777]

ed k, thanks, the napa store is close to my house but the guys that work there cant read the parts book and the place is allways a nut house. /ubbthreads/images/graemlins/crazyeyes.gif and yes keoke they said they dont handle stranded wire sets anymore for 8 or 6 cyl. great place to shop ha! /ubbthreads/images/graemlins/nonod.gif

 

[Keoke]

[ QUOTE ]
ed k, thanks, the napa store is close to my house but the guys that work there cant read the parts book and the place is allways a nut house. /ubbthreads/images/graemlins/crazyeyes.gif and yes keoke they said they dont handle stranded wire sets anymore for 8 or 6 cyl. great place to shop ha! /ubbthreads/images/graemlins/nonod.gif

[/ QUOTE ]

Well then Anthony, you need to go an have a talk with my friend "Virginia" down the road a piece.----Keoke-- /ubbthreads/images/graemlins/laugh.gif

 

[anthony7777]

keoke, i did exactly that on thursday,i labeled my local "napa" store as being a nut house /ubbthreads/images/graemlins/crazyeyes.gif, but there are no words in the english language to describe the bedlam at "virginias" place right now, oh shg. would be so-so proud, due "partly" to the move to thier new place,after 45 min. thier spools of the yellow "bumble bee" wire or the terminal ends could not be located, been waiting more then a month for a new # 2 carb. choke cable, i went back to the "nut house" yesterday with the number ed k. was kind enought to give me, and they found the wire set i needed, they now believe ed k. can walk on water too.thanks again ed k. see attch. /ubbthreads/images/graemlins/savewave.gif