Stock plugs better?

[HemiLover]

...in my case YES! I'm no expert, don't have a dyno and cant attest to everyones experience but here was my problem and solution:

In the midst of doing several performance mods to my R/T (CAI, pipes, SC Flashpaq, 176 degree Tstat) I also changed the spark plugs because it was over 36K (bought it used) and was fairly sure it hadn't been done. So of course I bought expensive bosch platinum +2's because they MUST perform better, right? Well sometime during all these mods I began to develop a slight "knocking" under acceleration. It coincidentally started happening almost immediately after the t-stat change but it wasnt that. Then I thought it was the SC flash....nope.... bad gas? Got 104+ and only run 91...nope there either! Then I read a thread about how good the stock plugs perform on the 5.7 and the light bulb went off! I cruised down to pep boys and spend a little over 20 bucks for the OE Champions, popped'm in and the knock is GONE!!! No performance difference either....
Just thought I would share.... I was SICK of hearing the knock so today was a good day

[FloridaRT]

I told you so!!!!!!!!!!!!!!!

LOL

Bob

[Hemi31]

Sounds like the Bosch plugs have a hotter heat range than stock.

[HemiLover]

I told you so!!!!!!!!!!!!!!!

Yes you did! I just wish I would have seen your advise a month ago!

Sounds like the Bosch plugs have a hotter heat range than stock.

That appears to be the case.... in fact the hotter the motor got the worse it got....I have the 176 t-stat and at or near that temp no problem, but once things started creaping up to 200+ it would come a knockin!

The funny thing is that Autozone and Kragen did not carry the "stock" plugs, only the platinum Champions and Pep Boys had the stock plugs in stock, but they werent listed for the 5.7 in their computer - I asked for them by part number and they had them listed for marine applications?? It's almost like they are bait-and-switching people to buy the more expensive platinum plugs!

[AWDJohn]

Can you post the Pep Boys Stock number please?

[HemiLover]

The stock number at all the stores i went to (pep's, kragen, autozone) was 570. When they hand them to you look at the box and it should say RE14MCC4.
The platinums are 3570.

[AJ_Gil]

This is only a seat of the pants opinion but I've had the Bosch +2 plugs in for about 6 months and am really happy with them. The thing seems to pull a bit better. No Superchips, but I have updated flashes, 180 degree Tstat, CAI & Zoomers. I recently upgraded to the AFE Stage II CAI and I can punch it at 10mph and get a little tire spin.
A bunch of forum guys are going to Moroso next month so I'll see if the times bear this out. Sure feels healthy

[Carfinish]

This is only a seat of the pants opinion but I've had the Bosch +2 plugs in for about 6 months and am really happy with them. The thing seems to pull a bit better. No Superchips, but I have updated flashes, 180 degree Tstat, CAI & Zoomers. I recently upgraded to the AFE Stage II CAI and I can punch it at 10mph and get a little tire spin.
A bunch of forum guys are going to Moroso next month so I'll see if the times bear this out. Sure feels healthy

I just changed mine over to Bosch 2s as well and the car feels like it pulls harder on take off and through 3rd gear....I've only got about 200 highway miles and liking them so far...I'll have to see how she does when it is really hot out although it was in the 90's ouple days this weekend and she ran fine...no knocking and when the car idles she sounds a little healthier...look for my write up soon.

[HemiLover]

Maybe with mine it was a combination of the plugs, sc 91 tune, less than great california gas and hot engine temps (hot days). The stock plugs helped me, and I too liked the bosch's when I first put them in.
Man I wish I could chirp at 10mph....it must be the fuzzy dice