Which plugs?
Thread Starter
Intermediate
Joined: Jul 2014
Posts: 29
Likes: 7
From: PA
Which plugs?
Hi all,
Ok, I have scoured the forum, but haven't found a lot of definitive info. I have a 1967 StringRay, but the engine is a 1968 427/400. I am looking at changing the plugs, but I'm not sure what to use. Currently, the car has Delco R44TS, but some of my searching suggests that these may not be the right ones. Can I run R44XLS or should I stick with the R44TS? Or do I consider a "43" series plug? Also, if I end up using a non-tapered plug, do I need to use the little metal gasket that comes with the plug? Sorry for all of the questions, but I just want to make sure I get this right! Just let me know if any other info is needed to answer my questions.
Thanks!
Ok, I have scoured the forum, but haven't found a lot of definitive info. I have a 1967 StringRay, but the engine is a 1968 427/400. I am looking at changing the plugs, but I'm not sure what to use. Currently, the car has Delco R44TS, but some of my searching suggests that these may not be the right ones. Can I run R44XLS or should I stick with the R44TS? Or do I consider a "43" series plug? Also, if I end up using a non-tapered plug, do I need to use the little metal gasket that comes with the plug? Sorry for all of the questions, but I just want to make sure I get this right! Just let me know if any other info is needed to answer my questions.
Thanks!
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
The stock plug 44TS should work fine. You can look up the cross over chart for other makes. For 20 years I've been hearing how champion plugs suck but I never had a problem. Accel, NGK and iridium plugs all work great but cost.
Crazy plugs like E3 I tried years ago and it wasn't worth it.
Crazy plugs like E3 I tried years ago and it wasn't worth it.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
ALL....... BB 396 and 427`s use a 3/4 reach plug....like .AC # R45XLS. The R45TS is a small block plug....any parts store should carry them. And while on the subject, .035 is the correct gap too...
Thread Starter
Intermediate
Joined: Jul 2014
Posts: 29
Likes: 7
From: PA
Thanks. So just to clarify, I should go with the XLS plug, correct? I am therefore assuming that the 44TS plugs were incorrect? Lastly, when installing new, non-tapered, plugs, do I need to use the metal gasket/washer on the plug? Thanks again!!
CF Community Team
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From: Cape Cod, Mass.
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with Wally, AC R45 XLS is what I use on my 68 427/390. It's the right plug for your 400 horse also.
Thread Starter
Intermediate
Joined: Jul 2014
Posts: 29
Likes: 7
From: PA
CF Community Team
Joined: Oct 2004
Posts: 19,355
Likes: 5,240
From: Cape Cod, Mass.
2025 C6 of the Year Finalist - Unmodified
2025 C8 Z06/7/E-Ray of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2021 C8 of the Year Finalist Unmodified
2020 Corvette of the Year Finalist (performance mods)
2019 C1 of Year Winner (performance mods)
2017 Corvette of the Year Finalist
2016 C2 of Year
2015 C3 of Year Finalist
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Race Director
Joined: Nov 2002
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From: Taylor Michigan
A few facts to help read plug information
R' is for resistor plugs
T' means used in tapered seat heads
S' is for extended electrode
Yes use the washer when installing the plug and head that requires them...and not all years are the same as the 454 engines do use a tattered seat plug correctly but not the 396/427`s