Small block shorty plugs

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Post Reply
mitch
Pro
Pro
Posts: 439
Joined: Fri May 11, 2012 8:38 am

Small block shorty plugs

Post by mitch » Thu Aug 31, 2017 10:17 am

Anyone have a spark plug recommendation for a small block chevy that is the shorty style. The car has AC delco cr43ts in it now and I am looking for something with more clearance for the headers
Thanks Mitch

pamotorman
Guru
Guru
Posts: 2295
Joined: Thu Mar 06, 2014 11:55 pm

Re: Small block shorty plugs

Post by pamotorman » Thu Aug 31, 2017 1:38 pm

a lot of lawn mower plugs are shorter the regular plugs

DCal
Pro
Pro
Posts: 452
Joined: Fri Aug 11, 2006 11:37 am
Location: mooresville nc

Re: Small block shorty plugs

Post by DCal » Thu Aug 31, 2017 3:08 pm

Acell used to sell a line of header friendly plugs but I can't remember any specific numbers.

mitch
Pro
Pro
Posts: 439
Joined: Fri May 11, 2012 8:38 am

Re: Small block shorty plugs

Post by mitch » Thu Aug 31, 2017 3:41 pm

I wound up using NGK 5673-7
thanks Mitch

Cutlassefi
Member
Member
Posts: 102
Joined: Mon Jul 22, 2013 9:17 am

Re: Small block shorty plugs

Post by Cutlassefi » Thu Aug 31, 2017 5:59 pm

FYI
https://www.holley.com/brands/accel/pro ... ark_plugs/
And it's Accel, not Acell. :D Just sayin.
Engine Builder, Accel, AEM, Comp, Erson, Holley, and Lunati Dealer

MikeB
New Member
New Member
Posts: 27
Joined: Wed Mar 22, 2017 10:44 am
Location: North Texas

Re: Small block shorty plugs

Post by MikeB » Wed Sep 06, 2017 9:52 am

I've used NGK and Bosch "ISO" style plugs to clear header tubes on several engines. Here's a comparison to a standard plug:

Image

Zmechanic
Pro
Pro
Posts: 282
Joined: Wed Oct 24, 2012 9:33 am
Location: Austin, TX

Re: Small block shorty plugs

Post by Zmechanic » Wed Sep 06, 2017 10:37 am

The autolite AR13x and AR13 series are just as short as the Accel "shorty" plugs, too. For whatever reason, they only seem to have AR13, which is a cold projected tip, or AR13x, which are various heat ranges of non projected tip.

User avatar
MadBill
Guru
Guru
Posts: 12620
Joined: Tue Nov 15, 2005 10:41 am
Location: The Great White North

Re: Small block shorty plugs

Post by MadBill » Wed Sep 06, 2017 10:46 pm

You know, I always ASSumed that shorty plugs had shorter insulators, leading (all else equal) to increased chance of spark tracking, but for this pair, the shorty has a slightly longer insulator! Why can't all common plugs be similarly shrunk? (I bet F1 plugs look like model aircraft glow plugs)
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.

HotRodRay
New Member
New Member
Posts: 23
Joined: Wed Aug 16, 2017 12:29 am

Re: Small block shorty plugs

Post by HotRodRay » Tue Sep 12, 2017 1:58 pm

MadBill wrote:You know, I always ASSumed that shorty plugs had shorter insulators, leading (all else equal) to increased chance of spark tracking, but for this pair, the shorty has a slightly longer insulator! Why can't all common plugs be similarly shrunk? (I bet F1 plugs look like model aircraft glow plugs)
Dialectric grease greatly reduces spark tracking.

Post Reply