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Discussion Starter · #1 ·
I saw this posted on another forum and thought that it might be helpful to post it here. This may be "sticky" material.

This is taken from Nitroustech.com and I've seen the same thing on many many forums. Figured we could have this here for everyone to use.

**Note: Heat ranges are determined by NGK standards. Not all plug manufacturers follow the same guidelines.

***Note: List is intended for reference only. Please consult with head mfg. and ignition mfg. for proper gap.

****Note: NGK IX and Denso plugs are Iridium.

LT1
Thread – 14mm
Reach - .708”
Socket – 5/8 hex
Seat - Taper
Stock Heat Range: 5
Gap: .050
Plug: NGK TR55 (stock number 3951); NGK TR55IX (stock number 7164); Autolite 764; Champion RS14YC6 (stock number 13); Denso IT-16 (stock number 5325)

Nitrous (one step colder)
Heat range: 6
Gap: .035 - .038
Plug: NGK TR6 (stock number 4177); NGK TR6IX (stock number 3689); Autolite 103; Denso IT-20 (stock number 5326)

Nitrous (two steps colder)
Heat Range: 7
Gap: Consult
Plug: NGK BR7EF (stock number 3346); NGK TR7IX (stock number 3690); Autolite AR94; Denso IT22 (stock number 5327)


LT1 w/ AFR heads
Thread – 14mm
Reach – 3/4”
Socket – 5/8 hex
Seat – Gasket
Stock – MFG Recommendations
Heat Range: 9
Gap: Consult ignition mfg.
Plug: NGK 5672A-9 (stock number 7405); Autolite AR3910; Champion C59YC (stock number 792); Denso IQ27 (stock number 5315); Denso IQ01-27 (stock number 5708)(diagonal platinum ground); Denso IQ02-27 (stock number 5711)(horizontal platinum ground)

Nitrous (one step colder)
Heat Range: 10
Gap: Consult ignition mfg.
Plug: NGK 5672A-10 (stock number 7942); Autolite AR50; Denso IQ31 (stock number 5323)

Nitrous (two steps colder)
Heat Range: 11
Gap: Consult ignition mfg.
Plug: Denso IQ34 (stock number 5324)


LT1 w/ Trick Flow & Edelbrock Heads
Thread – 14mm
Reach – 3/4”
Socket – 5/8 hex
Seat – Gasket

Stock – MFG Recommendations: approx under 9:1 compression
Heat Range: 4
Gap: Consult ignition mfg.
Plug: NGK FR4 (stock number 5155); NGK BKR5EIX (stock number 6341); Autolite 3926; Champion RC12YC (stock number 71); Denso IK16 (stock number 5303)

MFG Recommendations: approx 10.5:1 compression
Heat Range: 5
Gap: Consult ignition mfg.
Plug: NGK FR5 (stock number 7373); Autolite AR3924 (Racing Plug); Autolite 3924; Champion RC9YC (stock number 2075); Denso K20PR-U (stock number 3145); Denso IK20 (stock number 5304)

MFG Recommendations: approx 11:1 compression
Heat Range: 8
Gap: Consult ignition mfg.
Plug: NGK R5672A-8 (stock number 7173); Autolite AR3911; Champion C63YC (stock number 796); Denso IQ24 (stock number 5314)

MFG Recommendations: approx 12:1 compression
Heat Range: 9
Gap: Consult ignition mfg.
Plug: NGK R5672A-9 (stock number 7405); Autolite AR3910; Champion C61YC (stock number 785); Denso IQ27 (stock number 5315)

MFG Recommendations: approx 13:1 compression
Heat Range: 9 - 10
Gap: Consult ignition mfg.
Plug: NGK R5671A-9 (stock number 5238); Autolite AR3933; Champion C59CX (stock number 296); Denso IK27 (stock number 5312)

MFG Recommendations: approx 14:1 compression
Heat Range: 10
Gap: Consult ignition mfg.
Plug: NGK R5671A-10 (stock number 5820); Autolite AR3932; Champion C57CX (stock number 295); Denso IK-31 (stock number 5321)

**NOTE: Use chart for static compression and adjust heat range for nitrous use accordingly.
__________________
1996 DCM SS, ISSCA #1170
2005 Dodge Magnum RT

SSled now with ERE#4: 385 stroker with LE3 cam and LE-ported Trick Flow heads.
12.383 @ 109.2 mph, 4350 lbs. race weight at SSHS6
SSHS8 Bracket C Champion

I drive a hybrid - it burns both gas and rubber.

Putnam Park front straight:
 

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I reposted this once about a month ago and jonrobbins I think put it down into a readable post.
But with BK pretty much being the only active mod it got shuffled down the list.
Other than Paul, Bk and firewood in the wheel section, are any of the mods active? Might be time for some new ones!
I sent Hack a pm about helping out, but haven't heard anything back.
 

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Premium Member
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9,190 Posts
Discussion Starter · #4 ·
I reposted this once about a month ago and jonrobbins I think put it down into a readable post.
But with BK pretty much being the only active mod it got shuffled down the list.
Other than Paul, Bk and firewood in the wheel section, are any of the mods active? Might be time for some new ones!
I sent Hack a pm about helping out, but haven't heard anything back.
good stuff, thats the point of me posting to help rebuild the stickys, i saved alot of them but i noticed not too many got stickied. so if a mod sees this please delete or merge with Greens thanks
 
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