Gain extra benefits by becoming a Supporting Member Click here find out how!
Classic Performance Products Classic Parts
Ciadella InteriorsAmerican Auto Wire Classic Industries
Chevs of the 40sDanchuk Catalog
Hellwig Products IncPerformance Rod & CustomEcklers AutoMotive
Octane LightingNu-Relics Power Windows
Impala Bob's Bob's Chevy Trucks Bob's Chevelle Parts Bob's Classic Chevy

Username Post: Which spark plugs should I use?        (Topic#343421)
Valued Contributor
Posts: 3773
Age: 55
Loc: Anna Texas
Reg: 01-02-02
03-19-17 05:16 PM - Post#2682274    

Hello folks,

Highlander here, I have an old '66 C20 that I've been slowly restoring since 1994 and I'm wanting to tune the engine so I can get it registered and back on the road again.

I have a 5.7L SBC out of a 89ish Suburban or truck - not sure which. It has 193 center bolt "swirl port" heads. It used to be a TBI engine, but I converted it to a carburetor. I have the Summit 600cfm 4bbl unit. I am using a Mallory breaker less ignition distributer (non-HEI). It also has a set of Holley headers (if that's important)

It's bolted to a 700r4 o.d. transmission that turns a single Eaton 4:10 diff.

If someone could let me know the right plugs to install, and the proper gap that would work best with the configuration I'm using, I would really appreciate it.


-The Hilander.
A crystal red 2015 Impala Limited LTZ 3.6L sunroof
"Rattle can primer red" 1966 C20 Custom Camper 5.7L, 700 4R trans 410 diff. front disc, p/s
Project Pics


Valued Contributor
Posts: 4048
Loc: Sweden
Reg: 08-23-07
03-21-17 03:11 PM - Post#2682634    
    In response to hilandr451

Hi, Ac Delco R45TS, std gap .035".

You didn't say if you did anything to compression or cam... so I'm going to assume the std either 8.8:1 197hp or 9.3:1 210hp tbi 350 - then for sure the Ac Delco R45 TS, std gap .035". That's what the shop manual states for pretty much every low compression, low performance v8 after 1971 I ever had (of course most were lo-perf). mp;fea...


Icon Legend Permissions Topic Options
Report Post

Quote Post

Quick Reply

Print Topic

Email Topic

FusionBB™ Version 2.1
©2003-2006 InteractivePHP, Inc.
Execution time: 0.332 seconds.   Total Queries: 17   Zlib Compression is on.
All times are (GMT -0800) Pacific. Current time is 09:04 PM