bad plugs?

[Only4U]

i have the ole bosch platinum +4's. i've been told by several people they suck bigtime, but i don't know enough about the matter to be certain, and changing plugs is no easy chore. anyway, i was wondering if maybe the 10* of knock i was getting on 87 octane was due to these plugs. and now that i am running 93 octane and getting 3* of knock, if the plugs are also doing that. also i'm wondering if these plugs are hurting my performance at all or if they just aren't doing much good to them? thx a lot.

[Pathogen]

I've used pretty much any plug available to the general public, but liked my NGK's on my 3.4 the best.

If ya want bang for you're buck, think about checking Walmart and going with Champions. They're cheap and trustworthy.

Don't forget to set your gap (I'm thinkin' .035)

[Only4U]

it's actually .060

but are the bosch's sucky plugs and causing my knock? or are they just mediocre plugs that i probably shouldn't change unless it's up to my heart's content?

[GregWS6&Z28]

when i had my 3.4, I had no problems with the Bosch 4+'s. They come gapped to the correct specs

[Pathogen]

<blockquote>quote:</font><hr>Originally posted by Only4U:
it's actually .060

but are the bosch's sucky plugs and causing my knock? or are they just mediocre plugs that i probably shouldn't change unless it's up to my heart's content?<hr></blockquote>

yep - just looked that up . . . where the heck did .035 come in? lol

[Only4U]

<blockquote>quote:</font><hr>Originally posted by Pathogen:


yep - just looked that up . . . where the heck did .035 come in? lol<hr></blockquote>

haha, that's what the nitrous v6 f-body runner's gap their plugs at ;)

[Blazzin Joe]

<blockquote>quote:</font><hr>Originally posted by Only4U:
i have the ole bosch platinum +4's. i've been told by several people they suck bigtime, but i don't know enough about the matter to be certain, and changing plugs is no easy chore. anyway, i was wondering if maybe the 10* of knock i was getting on 87 octane was due to these plugs. and now that i am running 93 octane and getting 3* of knock, if the plugs are also doing that. also i'm wondering if these plugs are hurting my performance at all or if they just aren't doing much good to them? thx a lot.<hr></blockquote>

Your using platinum plugs with 87 octane fuel.. that could be your whole problem, try upgrading the fuel you use to 89 or 93 and that may help you problem...

[ravenp]

<blockquote>quote:</font><hr>Originally posted by Blazzin Joe:


Your using platinum plugs with 87 octane fuel.. that could be your whole problem<hr></blockquote>


How do you mean ?

[Blazzin Joe]

<blockquote>quote:</font><hr>Originally posted by ravenp:



How do you mean ?<hr></blockquote>


Higher octane fuels have more "chemicals" that slow the burn rate a bit, this may solve your problem. Switching to higher grade fuel, that is.

[ravenp]

Okay, sorry. That part I know, but I was curious as to how that relates specifically to 'platinum' plugs?

I was under the understanding it's best for performance to run on a lower octane fuel...

[Blazzin Joe]

<blockquote>quote:</font><hr>Originally posted by ravenp:
Okay, sorry. That part I know, but I was curious as to how that relates specifically to 'platinum' plugs?

I was under the understanding it's best for performance to run on a lower octane fuel...<hr></blockquote>


That goes with out saying, the faster the fuel can burn with out causing knock the better, but if you are getting knock it may be necessary to upgrade to higher grade of fuel..

His knock could becoming from his engine being to hot and his cooling system needs to be flushed / cleaned. There could be any number of reasons, but fuel would be one of the first things i would try to attempt to fix.

[ravenp]

Cool, thanks for the explanation.

So ideally if you can solve the knock without going with a higher octane, that would be better.

But it could cause the knock to stop which would be a good start, and perhaps help find the real problem right? THere's no reason a properly tuned N/A 3800 shouldn't be able to run optimumly(is that even a word?) [img]smile.gif[/img] ... on 87.

I had some knock on 87 that dispeared going to 89. I then did a few tuning things including adjusting my throttle position sensor and cleaning the injectors, and now it appears to be gone with 87 back in the car.

I might have gotten lucky.

[ January 16, 2003: Message edited by: ravenp ]</p>

[Blazzin Joe]

<blockquote>quote:</font><hr>Originally posted by ravenp:
Cool, thanks for the explanation.

So ideally if you can solve the knock without going with a higher octane, that would be better.

But it could cause the knock to stop which would be a good start, and perhaps help find the real problem right? THere's no reason a properly tuned N/A 3800 shouldn't be able to run optimumly(is that even a word?) [img]smile.gif[/img] ... on 87.

I had some knock on 87 that dispeared going to 89. I then did a few tuning things including adjusting my throttle position sensor and cleaning the injectors, and now it appears to be gone with 87 back in the car.

I might have gotten lucky.

[ January 16, 2003: Message edited by: ravenp ]<hr></blockquote>

To be honest, i wouldnt run any lower than 89 just for the reason that weather is uncontrolable and on the super hot days when your car is injesting hot air its easy for you to get some knock. But theoretically if the car was tuned right and had no power adders 87 should suffice.

[Only4U]

throttle position sensor? which sensor is that? and what did you do to it? i might should give that a shot to get rid of my knock...

[ravenp]

Well, like I said, I doubt it was related. It sure doesn't sound related, but after I did that and ran some injector cleaner and that 'guarenteed to pass emissions' stuff. Everything appeared fine.

The reason I adjusted the sensor is we discovered the reading was low using a voltmeter suggesting that I may not be getting WOT when I had the medal mashed. The readings with should have been close to 5 were only 4.36. I took the sensor off, bored out the drill holes so I could turn it a bit before refastening it.

Look in your manual for its' location. It's directly opposite the throttle cable where it joins up with the TB. Can't miss it [img]smile.gif[/img]

Again though, I'm not saying this will do any good... it was one of the things I did that day that's all.

[img]smile.gif[/img]