AC CR43TS or AC CR42TS ?

[6SENSE]

I know the archives say which ones to use if your running a certain ET, but I also know that most of that stuff was written with intercooled cars in mind. After all that we have learned about the differences with our hotair cars and the intercooled cars (what they react differently to) I was wondering what experiences you guys have had using the different (heat ranges of) plugs.
On a hotair when do you think you go with the 42's? After what mods? Which one do you guys prefer and have had experience with? Anyone have experience with both?
I have always used the 43's, but wasnt sure if the 42's would be a better choice with my mods.

Thanks guys, Justin

 

[Boost231]

hey

well i run AC-Cr42Ts in the summer and the AC-Cr43Ts in the winter. me and a friend both do this out here in arizona. if its cold run 43 if it gets hot out like summer time run 42

brent

 

[TType84]

go with the 42s

my car seemed to love them

i have ngk ur5's now..

think the 42s seemed to suppress knock a little more could be my imagination but the car knocked less with the 42s..

i think NGK UR6's would be equiv to 42s but im not sure

 

[crazygn]

good post , i think i'll try the 42's , because of running 23-25 psi it seems to die on the top end.

 

[6SENSE]

Thats what Im saying crazygn! Thats the type of boost that Im running too, and Topend/mph is what its all about as far as Im concerned. I can always work on the et, but I want to see that mph go up! I want to feel the car pulling strong all the way to the top of each gear, and if the 42's will help accomplish that then there going in! I had been wondering it, since weve got "hotter-air" flowing through our engines than our cold-air counterparts would it be a benefit to run the colder plugs, especially for those of us running higher boost.
Its the little things that often make the biggest difference with these cars, since its all about combination all the pieces need to complement each other inorder to get the best results.
Thanks for the replys guys, anyone else? More comments?

P.S. Are you guys gapping the 42's at .035 like we do the 43's?

 

[6SENSE]

Also, let me know if any of you think my thinking is off base with this (With the NA cars Ive often put in hotter plugs as an upgrade, but I know this is a totally different ballgame).
Im just looking for some of those "little things" that might help tie my combo together.

 

[WFO]

Originally posted by TType84

i think NGK UR6's would be equiv to 42s but im not sure

ngk ur5 is the same heat range as ac cr42ts.

ur4(or 45?) is the stock heat range.


later,sean

 

[6SENSE]

Im going to go exchange some new cr43's that I have sitting around for some 42's, and give them a try. Should I gap them at .035 ?

 

[turbo6x2]

I found the car runs better on the NGK UR5 with my combo. I don't get any stumble and they seemed to help the overall performance. Just my 2 cents for what it's worth.

 

[6SENSE]

Why is it that no one sells CR42TS's ? Ive tried four places and no luck so far (Auto Zone, Advanced Auto Parts, Napa, and a local All Pro parts store).
Since Ive been trying to tune for no KR lately, Ive got the boost down lower than usual (17psi w/FP at 43). Since I turned the boost down Ive been getting a bit of a stumble and an occasional backfire from the intake, but no KR. I think the car liked running lean, maybe its refusing to burn the gas now .

Maybe I will try those NGKUR5s. Who sells them? What gap? Ya think they might be good for my combo below?

 

[crazygn]

17psi and 43 psi fuel press i would think it would be a little on the rich side, but most intake backfires are from running lean.

let me know how the plugs work iam going to change mine when my headers getting here.

 

[6SENSE]

Well, I hate to do it, but I might have to.....turn the boost back up a little!

I will let you know on the plugs crazy, as soon as I find out where to get some ...... oh yeah, and what to gap em at.

 

[6SENSE]

Oh well, I guess I will have to........... turn the boost back up a little bit (and I was trying to be good).

I will let you know on those plugs crazy, as soon as I find out where to get them.... oh yeah, and what to gap them at.

 

[crazygn]

I gaped my 43's at .32 for the higher boost , i would guess about the same .32-.35

 

[6SENSE]

Hey, I wonder if I should just try a lower gap on the 43s Ive got? (Currently at .035).
What is the general reasoning used on deciding on the gap? Or is it just trial and error? Were you thinking that the higher boost was blowing them out? (Dont know if this is a dumb question or not, Im starting to get tired )

 

[crazygn]

could be making a weak spark at high boost, cutting the gap down some might help out. My slf i think iam going to find the 42's and gap them at 32-35 and see what happens

 

[WFO]

i run the ngk ur5's gapped from .030 to .032 depending on what boost i'll be running.the higher the boost/timing(cylinder pressure) the greater chance the spark will be blown out,hence the need for tighter gaps.

later,sean

 

[6SENSE]

Yeah, Im with you on that. If I can only find them. I guess the dealer might have them. Just seems kind of silly going to the dealer for spark plugs.
If those NGK UR5s are the equivalent I guess they are an option.

The whole deal is that I know there is something silly that is just out of tune with my car, dont know how big a difference the plugs will make, but anything I can do to move in the right direction is what Im looking for. 14.2@96 is just not cutting it with my mods! I need more topend, which SHOULD BE no problem with my intake and turbo.

 

[FJM568]

I've bought the NGK's at NAPA...I think also at O'Reilly's as well...I have also bought the CR43's at O'reilly's with no problem...They seemed to have them in stock...Not sure with the CR42's, haven't tried them out...

But I will say, that I do like the NGK's...I'm running the UR5's...

 

[turbo6x2]

Originally posted by WFO
i run the ngk ur5's gapped from .030 to .032 depending on what boost i'll be running.the higher the boost/timing(cylinder pressure) the greater chance the spark will be blown out,hence the need for tighter gaps.

later,sean

I believe we have ours gapped at .030 and that seemed to work the best.. for our set up anyway. We get ours at napa same with the ac delco you're looking for, did you ask the parts guy if he could order, they do around here. (cr43ts)