Spark Plug Recommendations

[ryan_thompson87]

Ive been wondering what I should be running for spark plugs, as I think thats whats causing my idle and driveabilitly problems. I think I need a higher heat range. The motors a 355 with about 9.6:1 compression, Vortec heads, GMPP TBI Vortec Intake, A Mild Cam, and headers. It idles like crap and surges abit going down the road. Sometimes there is a misfire also.

[pfk]

(I just noticed, you posted in the wrong section ;) )


What spark plugs are you running right now?

I completed a little experiment today concerning spark plugs in vortec heads and I found out after several ins and out of the plugs, do not use cr43ts plugs in vortec heads.

Even though I am still tracking down some issues with my truck, I have been very happy with its performance. While trying to find a reason for my datalogging errors, I started pulling plugs to see if any of them showed signs of misfiring. (I was using 41-932 plugs) while trying to squeeze around the headers, I managed to break one, and go figure, I am out of stock on those plugs. I figured what the hell, I'll try some cr43ts since I have some here. It idled fine and seemed to run fine until I took it out on the road. The truck no longer had any power (it drove almost like it did pre mods) I am just finshing them up now (putting the 932's back in) I more than likely wont go for a drive until tomorrow since I am trying to keep the engine from heating up, I'd like to keep trying to track down these errors

but as far as cr43ts's are concerned, I would say they are a bad choice in vortec heads. If you look at the 41-932 beside a cr43ts you will see that the 932 electrode will sit quite a bit farther into the combustion chamber. Another plus of these plugs is that the tip sticks out less than the cr43ts for those of us with annoying headers and limited space.

I also found out today that the 41-932's have changed up to 41-993. (these were the plugs that came in a 97 chev 5.7 vortec stock)

http://i188.photobucket.com/albums/z60/pfk_ca/July-4-2007-034.jpg

[ryan_thompson87]

Right now I'm running the cr43ts. I've been told to stick to delco plugs in the past so Ill try the 932s thanks. And Yea I know i put it here I figured it was TBI and lacking the performance it had lol

[Fast305]

I am running a different plug it is a R42LTS, just a copper tip long reach "VORTEC" style plug. It is like $1.29 each compared to the $5.99 of the Platinum plugs used by GM.

[93ChevyTBI]

I am running a different plug it is a R42LTS, just a copper tip long reach "VORTEC" style plug. It is like $1.29 each compared to the $5.99 of the Platinum plugs used by GM.
This is what I'm running as well. Power-wise I can't tell the difference but they do make it run a lot smoother.

[oldred95]

I just got done test driving after swapping out the CR43TS's for the correct R44LTS's and I can't say that it made a huge difference but the difference was there. Not so much in power, but in response and it did smooth things out some. One thing I did notice is I started getting spark knock at WOT which I hadn't been getting before but I haven't driven it when its this hot out either since I put the vortec heads on it.

[91chevZ71]

I am running a different plug it is a R42LTS, just a copper tip long reach "VORTEC" style plug. It is like $1.29 each compared to the $5.99 of the Platinum plugs used by GM.

I am gonna give those plugs a try...getting sick of spending almost 60 bucks when I change plugs

[oldred95]

I am gonna give those plugs a try...getting sick of spending almost 60 bucks when I change plugs
Yea no reason to ever pay that much for plugs. I got my R44LTS's for 2.09 a piece though. It was the going rate around town. Rockauto was like 1.78 not sure how or where Chris is getting them for 1.29 a plug.

[91chevZ71]

where did you the AC delco's for 2.09??

[Fast305]

Rockauto was like 1.78 not sure how or where Chris is getting them for 1.29 a plug.

From NAPA through the Nissan Dealership I work at.

[oldred95]

where did you the AC delco's for 2.09??
Napa, Oreilly's, Autozone

[91chevZ71]

I got raped at NAPA...5.39 per plug

[oldred95]

I got raped at NAPA...5.39 per plug
Thats napa for ya.

[pfk]

What are you guys running for gap on the LTS plugs?
I may change my platinums out tomorrow and figured I'd ask first.

[91chevZ71]

I gap mine at .060 (stock for the vortec trucks, I believe.)

although I have read some things saying to gap them at .045.
I have all that MSD crap so I can have a bigger gap than .045, I think.