Spark plugs and gap for 041 heads, mallory ignition

[eduardocastrejon]

Hi,

Please help me with this

2110cc 041 cb ported heads dual idf, nitrous, 125 cam, 9.1 cr

I want to know what are the best spark plugs and gap for my application, I live in a hot place

Ignition is mexican electronic distributor, mallory 685 box, mallory 440 coil, taylor 409 cables

I don't have access to many options of spark plugs, at this moment I'm using bosch super w8dc.
I bought at cb heads some plugs but they sent me ngk  dp8ea9 but this plugs are 12mm  3/4 long and I need 14mm 1/2

1.- what spark plugs ?
2.- what gap ? street aplication

3.- do i need to use another type of spark plugs and gap for nitrous ?

thanks in advance

[Ohio Tom (DdK)]

for plugs, you'll get lots of recommendations.
NGK's seem to be main stream choice.
They all seem to work fine. bosch, NGK, Autolite, (just not champions).

For the last few years I have been using Autolite plugs.
for my 3/4 reach plugs I like the 5502's.
I like them because they use 5/8" socket which clears my welded manafolds and trimmed out cyl tins.
That's the only real reason. And they are in-stock at my local autoparts store. Cheap too.
I use them on my 12.6/1 N/A race motor gapped about .045".
For my street turbo motor, I gap them at .024".
Any more and I run into crossfire issues under boost. (not the plugs fault).
To me, the brand sparkplug doesn't make that much differnce as long as the threads are "rolled" and not "cut".

[eduardocastrejon]

thanks

then .024 for my na street motor an ocasionally nitrous shot will work ?

[Ohio Tom (DdK)]

Yeah, that should be fine.

[bowen71]

I installed a MSD 6A box with a Bosch blue coil and when I read the plug gap reccomendations on MSD and it goes by C/R. The lower the C/R the higher the gap.  I gapped mine like it said which is at .050 what do you all reccomend?

2110
8.2:1 C/R
42x37.5
1.4:1 Rockers
K8 Cam
1 5/8 Sidewinder
Dual 44 IDF's