BB spark plug question
Thread Starter
Burning Brakes
Joined: Feb 2009
Posts: 958
Likes: 192
From: Downingtown Pa.
BB spark plug question
I have one of the 2002 built ZL-1's in my Mongoose GS. Pulled a few plugs after a drive to see how the Hilborn efi is doing. Engine has NGK V power 7 in it. Number on bottom boss is R5671A-7 . Looking in my ZL-1 info it lists two different A/C plugs for this motor on two different Chevy sheets. One is a R43LTS the other a R43XLS. Any idea what the difference is between a LTS and a XLS series plug. Plugs don't look that bad but I have to admit I'm a old A/C man. Been a long time since I have been fooling around with plugs and the internet runs me around in circles trying to determine the difference !!------------- Ken
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
II`ll try, basically what I wrote below
I have one of the 2002 built ZL-1's in my Mongoose GS. Pulled a few plugs after a drive to see how the Hilborn efi is doing. Engine has NGK V power 7 in it. Number on bottom boss is R5671A-7 . Looking in my ZL-1 info it lists two different A/C plugs for this motor on two different Chevy sheets. One is a R43LTS the other a R43XLS. Any idea what the difference is between a LTS and a XLS series plug. Plugs don't look that bad but I have to admit I'm a old A/C man. Been a long time since I have been fooling around with plugs and the internet runs me around in circles trying to determine the difference !!------------- Ken
R45XLS ....R resister, 43 heat range, gasketed X 3/4 reach, S extended tip....396/427, also fits Hemi`s
whats a mongoose?
Thread Starter
Burning Brakes
Joined: Feb 2009
Posts: 958
Likes: 192
From: Downingtown Pa.
Thanks alot !!! Interesting that GM on one page says use a gasketed plug and on another a tapered seat plug !!! Whats in it now has the gasket. I did finally remember what some of the plug id means. The 4 in 43 is for the 14 mm threads, 3 is the heat range. Been a long time since I dealt with this stuff.
Mongoose is Mongoose Motorsports . They build the GS replica's . ----------- Ken
Mongoose is Mongoose Motorsports . They build the GS replica's . ----------- Ken
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
Thanks alot !!! Interesting that GM on one page says use a gasketed plug and on another a tapered seat plug !!! Whats in it now has the gasket. I did finally remember what some of the plug id means. The 4 in 43 is for the 14 mm threads, 3 is the heat range. Been a long time since I dealt with this stuff.
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Thread Starter
Burning Brakes
Joined: Feb 2009
Posts: 958
Likes: 192
From: Downingtown Pa.
Just pull a plug and check the seat in the head - if it's flat it takes a gasketed plug, if it's tapered it takes a "T" ("peanut") plug. 43 is too cold for normal operation - that's a race plug; for normal operation, 45 is a better heat range. R45XLS plugs work great in gasketed 427's.
Burning Brakes
Joined: Nov 2006
Posts: 844
Likes: 5
From: Pasadena TX