Are Ac Delco R45TSX factory plugs in an 87 350? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

weider1717 · 03-12-2016, 10:15 PM

That is what I pulled out of mine making sure before I put the wrong plug in I want in exactly what it came with new.

Thanks

**bhc41051** · 03-13-2016, 12:20 AM

R43TS, CR43TS, 41-817 (platinum) or 1 (Rapidfire). I looked on eBay for a set of NOS ACNITER II plugs for my 75.

rich weyand · 03-13-2016, 02:00 AM

Current GM 350 crate engine spec says R45TS is recommended plug.

weider1717 · 03-13-2016, 04:02 AM

Thanks I couldn't find anything on it and these look so old I bet they're original to the truck it has 69k miles on it.

weider1717 · 03-13-2016, 05:41 AM

I found paperwork where the plugs were replaced in 1996 with the R45TSX that I pulled out.

Anyone care to give their op on these plugs? From my research the X for extended gap was used more in like 1975 years of smog stuff got big and are not for this truck but not 100%.

Thinking I need R45TS and not R45TSX

anyone?

Pontiac1976 · 03-13-2016, 06:06 AM

R45TS what it was out of the factory. It's been some time since I have did a older plug change. But If I remember one a hotter plug one is a colder plug. If go to auto store that have them on a rack you will see the one has the electro sticking out more( hotter plug ),
one electro is in side the thread part of the plug a ( colder plug ) when you doing a tune up in you plugs to brown or to milky white you would put in plug get the electro closer or away from the piston to get a better burning plug. when using header run hotter so some time you need a colder running plug. This is also depends on carb or EFI setting & checking plugs.

Blessed66 · 03-13-2016, 10:31 AM

Run with the R45TS. It will be just fine.

**bhc41051** · 03-13-2016, 10:38 AM

From the parts book. Not sure if production or replacement.

Front Range · 03-13-2016, 11:42 AM

This might help.

Delco Spark Plug Decoder

Spark Plug Cross Reference

weider1717 · 03-13-2016, 12:29 PM

Thanks! Looks like the book calls for R43TS for an 87 350 tbi. Thats what I'll run with unless someone says otherwise.

Did read the 45 burns hotter and stays cleaner

Blessed66 · 03-13-2016, 01:36 PM

Quote:

Originally Posted by weider1717

Thanks! Looks like the book calls for R43TS for an 87 350 tbi. Thats what I'll run with unless someone says otherwise.

Did read the 45 burns hotter and stays cleaner

Emphasis, mine. For a mostly stock application, I'll suggest hotter plugs. If it's a monstrously built engine, more often than not, I never had to make a suggestion, the customer had his or her ideal plug choice, already.

Jake Wade · 03-13-2016, 05:26 PM

The Vin K (TBI) engines of that era (87-95) came with CR43TS. NGK UR5 is a good alternative.

weider1717 · 03-13-2016, 06:30 PM

Quote:

Originally Posted by Jake Wade

The Vin K (TBI) engines of that era (87-95) came with CR43TS. NGK UR5 is a good alternative.

I finally found my manual and it shows the CR for the 7.4 and the R43TS for the 5.7

I think the only difference is the CR is commercial though

Blessed66 · 03-13-2016, 07:11 PM

Quote:

Originally Posted by weider1717

I finally found my manual and it shows the CR for the 7.4 and the R43TS for the 5.7

I think the only difference is the CR is commercial though

Just remember, when it comes to manuals, that fuel has changed a lot since 1987. I'm not saying you can't run R43TS, I'd go to the 45, though. Just my .02...

weider1717 · 03-16-2016, 08:35 PM

Quote:

Originally Posted by Blessed66

Just remember, when it comes to manuals, that fuel has changed a lot since 1987. I'm not saying you can't run R43TS, I'd go to the 45, though. Just my .02...

I got 45's in just curious whats the 45's do thats a positive over the 43's with todays gas? thanks

rich weyand · 03-16-2016, 08:50 PM

The heat at which the plug runs goes up with the number for ACDelco plugs.

A 45 will be less prone to fouling than a 43.

03-12-2016, 10:15 PM	#1
weider1717 Registered User Join Date: Apr 2011 Location: greenville sc Posts: 558	Are Ac Delco R45TSX factory plugs in an 87 350? That is what I pulled out of mine making sure before I put the wrong plug in I want in exactly what it came with new. Thanks Last edited by weider1717; 03-12-2016 at 10:25 PM.

03-13-2016, 12:20 AM	#2
bhc41051 Senior Member Join Date: Apr 2012 Location: Otway OH Posts: 788	Re: Are Ac Delco R45TSX factory plugs in an 87 350? R43TS, CR43TS, 41-817 (platinum) or 1 (Rapidfire). I looked on eBay for a set of NOS ACNITER II plugs for my 75.

03-13-2016, 02:00 AM	#3
rich weyand Registered User Join Date: Apr 2014 Location: Bloomington Indiana Posts: 1,041	Re: Are Ac Delco R45TSX factory plugs in an 87 350? Current GM 350 crate engine spec says R45TS is recommended plug. __________________ Rich Weyand 1978 K10 RCSB DD.

03-13-2016, 04:02 AM	#4
weider1717 Registered User Join Date: Apr 2011 Location: greenville sc Posts: 558	Re: Are Ac Delco R45TSX factory plugs in an 87 350? Thanks I couldn't find anything on it and these look so old I bet they're original to the truck it has 69k miles on it.

03-13-2016, 05:41 AM	#5
weider1717 Registered User Join Date: Apr 2011 Location: greenville sc Posts: 558	Re: Are Ac Delco R45TSX factory plugs in an 87 350? I found paperwork where the plugs were replaced in 1996 with the R45TSX that I pulled out. Anyone care to give their op on these plugs? From my research the X for extended gap was used more in like 1975 years of smog stuff got big and are not for this truck but not 100%. Thinking I need R45TS and not R45TSX anyone? Last edited by weider1717; 03-13-2016 at 05:48 AM.

03-13-2016, 06:06 AM	#6
Pontiac1976 Registered User Join Date: Oct 2015 Location: Ottawa, Ontario, Canada Posts: 769	Re: Are Ac Delco R45TSX factory plugs in an 87 350? R45TS what it was out of the factory. It's been some time since I have did a older plug change. But If I remember one a hotter plug one is a colder plug. If go to auto store that have them on a rack you will see the one has the electro sticking out more( hotter plug ), one electro is in side the thread part of the plug a ( colder plug ) when you doing a tune up in you plugs to brown or to milky white you would put in plug get the electro closer or away from the piston to get a better burning plug. when using header run hotter so some time you need a colder running plug. This is also depends on carb or EFI setting & checking plugs. __________________ 1977 REG cab Long Bed with a 1984 Front Clip, 82 305 .60 over 9.0.1 flat top pistons, 4bbl, TH350, w/84 SS-intake & cam , w/ 1977 big block rad, 1975 gear box, 1984 master w/ metric fittings top & SAE fitting @ portion block, 1975 3.42 gear open diff. Duel 77-87 Factory air cleaner, duel inlet from rad support . Down sized 9' to new 8' Steel flat bed Was a 77 454 w/308 gear. Taken out 550 lbs. up front with motor clip change.

03-13-2016, 10:31 AM	#7
Blessed66 Registered User Join Date: Oct 2012 Location: Tyler, Texas Posts: 217	Re: Are Ac Delco R45TSX factory plugs in an 87 350? Run with the R45TS. It will be just fine. __________________ Current Projects: 1984 GMC, LWB Fleetside, 305/350 - Currently Doing TBI Conversion 1966 GMC, SWB Stepside, 350/200-4R - Currently waiting patiently.

03-13-2016, 10:38 AM	#8
bhc41051 Senior Member Join Date: Apr 2012 Location: Otway OH Posts: 788	Re: Are Ac Delco R45TSX factory plugs in an 87 350? From the parts book. Not sure if production or replacement. Attached Images

03-13-2016, 11:42 AM	#9
Front Range Registered User Join Date: Jun 2014 Location: Longmont, Colorado Posts: 252	Re: Are Ac Delco R45TSX factory plugs in an 87 350? This might help. Delco Spark Plug Decoder Spark Plug Cross Reference __________________ Folks that throw dirt on you aren't always trying to hurt you, and folks that pull you out of a jam aren't always trying to help you.

03-13-2016, 12:29 PM	#10
weider1717 Registered User Join Date: Apr 2011 Location: greenville sc Posts: 558	Re: Are Ac Delco R45TSX factory plugs in an 87 350? Thanks! Looks like the book calls for R43TS for an 87 350 tbi. Thats what I'll run with unless someone says otherwise. Did read the 45 burns hotter and stays cleaner

03-13-2016, 05:26 PM	#12
Jake Wade Registered User Join Date: Aug 2005 Location: Louisiana Posts: 711	Re: Are Ac Delco R45TSX factory plugs in an 87 350? The Vin K (TBI) engines of that era (87-95) came with CR43TS. NGK UR5 is a good alternative.

03-16-2016, 08:50 PM	#16
rich weyand Registered User Join Date: Apr 2014 Location: Bloomington Indiana Posts: 1,041	Re: Are Ac Delco R45TSX factory plugs in an 87 350? The heat at which the plug runs goes up with the number for ACDelco plugs. A 45 will be less prone to fouling than a 43. __________________ Rich Weyand 1978 K10 RCSB DD.



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