DZ Spark Plugs?
 

Who's using what spark plugs for 69DZ. Want to put a fresh set in. Thanks.

Re: DZ Spark Plugs?
 

Rob,
I have AC R44 plugs in one car and AC 43's in the other. I just pulled them and I would recommend the AC R44...they appear to burn better. The AC R44 car has headers and is 'driven'. The AC 43 car is a 'trailer queen'.

Re: DZ Spark Plugs?
 

I had 44s on my car before I pulled the motor. Pretty happy with them. I will be using them again. I used my car quite a bit last summer to. https://www.yenko.net/ubbthreads/imag...ins/3gears.gif

Re: DZ Spark Plugs?
 

44's. https://www.yenko.net/ubbthreads/imag...ins/3gears.gif https://www.yenko.net/ubbthreads/imag...ns/burnout.gif

Re: DZ Spark Plugs?
 

Thanks for the info. Just got back from Lee Auto parts in Crystal Lake. They do not list AC R44's. They had R43's and R45's. Where do I find 44's? Thanks

Re: DZ Spark Plugs?
 

NAPA-Carquest-Auto Zone-Murrays all carry the AC R44 over here.

Re: DZ Spark Plugs?
 

Thanks. Lee's counter person look at me like I was nuts.

Re: DZ Spark Plugs?
 

[ QUOTE ]
Thanks for the info. Just got back from Lee Auto parts in Crystal Lake. They do not list AC R44's. They had R43's and R45's. Where do I find 44's? Thanks

[/ QUOTE ]45's wouldn't hurt you either. JMO

Re: DZ Spark Plugs?
 

[ QUOTE ]
44's. https://www.yenko.net/ubbthreads/imag...ins/3gears.gif https://www.yenko.net/ubbthreads/imag...ns/burnout.gif

[/ QUOTE ]

Re: DZ Spark Plugs?
 

The 43's in a trailer queen may foul easier...the hotter 44 or 45 would be better in that one...

Re: DZ Spark Plugs?
 

I just pulled out the Original Factory AC 4 green ring R43T's yesterday in my trailer queen,and installed NGK UR5's,per Robs advise.
HOLY CRAP! https://www.yenko.net/ubbthreads/imag...emlins/eek.gif It feels like I added 10 more Horse Power with a much better start up & a responsive throttle as never before.
You should see how Fouled my old R43T's look.
Thanks Rob & Marlin
Lifes too short to stare at your Car.. https://www.yenko.net/ubbthreads/imag...ns/burnout.gif

Re: DZ Spark Plugs?
 

I've been trying to tell you folks...I think more people would be surprised if they'd just give 'em a try...you AC folks just don't know what you're missing!

BTW: what did you end up paying for the NGKs up your way?

Re: DZ Spark Plugs?
 

I couldn't get R43 or 44 for that matter...I put a set of some kind of platinum Bosch plugs in it and it seems to run pretty good. What number NGK for these LT1's Rob ?

Re: DZ Spark Plugs?
 

Yeah I'll go for a change. What is the 44 equivalent?

Re: DZ Spark Plugs?
 

I called all the local Auto parts stores here,most said they would have to order the NGK #UR5,& are $2.80-3.25 a plug.
I found ONE local NAPA store that had 8 on the shelf for $1.76 each,so I drove over to pick them fast as opposed to waiting a few days & paying more to the others.
I have no idea why this one store had my plugs in stock,and for so much less?
Neither did the store clerk.
(By the way Rob,NGK Technical hotline does not show my 1970 396/291 head application,they kept saying I should use the 840 head application & gave me the NGK equivalent number.I told them to update their records as the 1970 L78 is a 291,not 840 head. https://www.yenko.net/ubbthreads/imag...ns/Charley.gif )

Re: DZ Spark Plugs?
 

I use R45's for the street and cruising, but re-install R43's for SCR racing - remember the spark plug delivery to the meet-n-greet in the parking lot by the local Chevy dealer?

I have fouled several sets of R43's, (not my NOS set of 4 thin lined ones though), and found that the hotter R45 worked much better. I will give the NGK's a try though, as the R45's will foul occasionally too, especially after idling in line at a cruise or a show.

Re: DZ Spark Plugs?
 

NGK's https://www.yenko.net/ubbthreads/imag...iggthumpup.gif trick is to find them for a couple bucks a plug..we used to get them from Al's for about what Rick picked his up for then Chucks bought them out...now there back up to 5 to 8 bucks a plug...we need to find a online place to get them priced fairly...throttle response with them is usually real good.

Re: DZ Spark Plugs?
 

NGK appears to have a million different indentifiers for their plugs. How the heck did you decode UR5 for your L78. My car decodes to B6S for an R44. With the middle number being the heat range 5-6-7. 6 being middle. replacement. https://www.yenko.net/ubbthreads/imag...lins/dunno.gif https://www.yenko.net/ubbthreads/imag...s/confused.gif

Re: DZ Spark Plugs?
 

Rob had mentioned these... web page

Re: DZ Spark Plugs?
 

Are NGK that much better than the Autolites? Whats the # for the 69 Z's? Thanks, Sam

Re: DZ Spark Plugs?
 

Sam --Rob did performance comparison tests on the dyno and he said he saw the difference with the NGK's performance.I've got an electronic ignition so I can open the gap or file back the ground rod a bit and my unit will fire pretty hot.----- I've got no complains with AC, BUT dynos don't lie, Rob said it performed super. I did however find that the AC 44 or 45 did keep a "STREET TUNE" longer than the NGK IN MY CASE-- also AC 43 is a little too cold if your not gonna blow out the carbon now and again....----------I would guess Rob would be able to give you a number for your Z............ https://www.yenko.net/ubbthreads/imag...lins/beers.gif

Re: DZ Spark Plugs?
 

Thanks Joe. I am thinking about using some of my NOS AC 44's for the street. (AC's look better) I have been using Autolites with good results. Maybe the NGK's are even better??!! Need to get the right heat range for the NGK. Thanks!

Re: DZ Spark Plugs?
 

Here is what NGK shows for the '69 Z28: CLICK HERE

I'm personally not up on the small block NGK plugs, but our dyno guy should be...

Re: DZ Spark Plugs?
 

Yeah they do look better--guess it's a sentimental thing........ https://www.yenko.net/ubbthreads/imag...mlins/grin.gif

Re: DZ Spark Plugs?
 

Thanks Rob! Sam

Re: DZ Spark Plugs?
 

[ QUOTE ]
Thanks Rob! Sam

[/ QUOTE ]

I second that thanks! https://www.yenko.net/ubbthreads/imag...lins/beers.gif

Re: DZ Spark Plugs?
 

Marlin/ Frank...what jets are you running front and rear ?

Re: DZ Spark Plugs?
 

NGK https://www.yenko.net/ubbthreads/imag...iggthumpup.gif

Re: DZ Spark Plugs?
 

www.rockauto.com/ 3332/XR5 NGK $1.61 each, comes in 4 pack.

Re: DZ Spark Plugs?
 

[ QUOTE ]
www.rockauto.com/ 3332/XR5 NGK $1.61 each, comes in 4 pack.

[/ QUOTE ]

never heard of them..John you order from them on a reg basis???

Re: DZ Spark Plugs?
 

Never have purchased from Rock Auto. I was researching to see if the XR5 plugs used gaskets or tapered seats to seal when I found them. Since I'm an auto parts sales rep, I'm gonna see if I can get them through my warehouse sources. Just thought you guys might want a good price before I find if I can get them myself.

Re: DZ Spark Plugs?
 

https://www.yenko.net/ubbthreads/imag...iggthumpup.gif

Re: DZ Spark Plugs?
 

John, you're an old small block guy...do those XR5's look right?

Re: DZ Spark Plugs?
 

Yah Rob, the XR5's are a 3/8 reach gasketed plug with a 13/16 hex. A-ok for a 69 Z28. The UR5's are a .460 reach with a tapered seat and a 5/8 hex for the later stuff.

Any time there is free horse power to be had my eyes and ears really perk up! https://www.yenko.net/ubbthreads/imag...ns/burnout.gif

Re: DZ Spark Plugs?
 

did you guys find a online chart to cross over plugs from existing brands???? I need some to for the new motor...

Bud.

Re: DZ Spark Plugs?
 

[ QUOTE ]
Marlin/ Frank...what jets are you running front and rear ?

[/ QUOTE ]

For the street or for racing?

Re: DZ Spark Plugs?
 

both !!!

Re: DZ Spark Plugs?
 

I don't recall.
https://www.yenko.net/ubbthreads/imag...mlins/grin.gif