Bosch Platinum 4 Plugs
Racer
Joined: May 2001
Posts: 320
Likes: 0
From: TX
Re: Bosch Platinum 4 Plugs (tkrussell)
Buy the standard platinum or NGK plugs. I didn't notice any difference. The price difference is just not worth it. I think you would get more performance gains by changing plugs once a year which would cost the same as changing the +4's every 3 years.
Burning Brakes
Joined: Feb 2002
Posts: 1,232
Likes: 10
From: Montrose Colorado
Re: Bosch Platinum 4 Plugs (kkonen)
I run the +4's in the my 84 CF and 91 ZR-1 they seem to work fine. I'm not going to claim any great performance gains, but like I say they seem to work fine. 84 CF 91 ZR-1 #2039
Drifting
Joined: Jun 2001
Posts: 1,997
Likes: 1
From: Lake Ozark MO
Re: Bosch Platinum 4 Plugs (tkrussell)
No performance gain... the stock plugs worked great (on a '96)... but the +4's definitely don't perform any worse than the stockers. I've had the +4's in for about 10K and no complaints.
I'm with the above post on staying with the stock or (always good) NGK's.
No reason to waste good money.
I'm with the above post on staying with the stock or (always good) NGK's.
No reason to waste good money.
Melting Slicks
Joined: Apr 2002
Posts: 3,019
Likes: 0
From: down that one road next to that big tree
Re: Bosch Platinum 4 Plugs (Dan Parker '96)
i love bosch plugs but for what they cost you could replace normal platinum plugs at least twice. did i ever tell you what my oppinion on spark plugs was? well my favorite is one that's changed often :yesnod:
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Re: Bosch Platinum 4 Plugs (tkrussell)
My son installed the Bosch +4 in his 1993 Ford Probe and the engine hesitated badly and would not rev over 4000 rpm. After a day of trying different things, we dropped it off at a shop and when I said we installed the +4's, the mechanic said that was likely the problem. He installed cheap NGKs and it runs like a champ now.
Although this was not a Corvette, I will never use the +4s in my car.
Last year, I installed the OEM AC Delco and the engine runs great.
Although this was not a Corvette, I will never use the +4s in my car.
Last year, I installed the OEM AC Delco and the engine runs great.
Drifting
Joined: Aug 2001
Posts: 1,550
Likes: 27
From: Minneapolis MN
Re: Bosch Platinum 4 Plugs (Mez)
My son installed the Bosch +4 in his 1993 Ford Probe and the engine hesitated badly and would not rev over 4000 rpm. After a day of trying different things, we dropped it off at a shop and when I said we installed the +4's, the mechanic said that was likely the problem. He installed cheap NGKs and it runs like a champ now.
Although this was not a Corvette, I will never use the +4s in my car.
Although this was not a Corvette, I will never use the +4s in my car.
For some reason the Probe hates the +4s. I noticed much better performance with NGKs compared to the +4s in my old probe. For the Vette, stick with ACDelcos, don't was your $$ on Bosch. :U
Racer
Joined: Feb 2001
Posts: 292
Likes: 0
From: hialeah fl florida
Re: Bosch Platinum 4 Plugs (tkrussell)
I have them in my 92 and after 3000 miles no problems and mid range it feels smoth my idle was a litte better over ngk on the other hand i put them in my wife benz S500 and it made huge diff over stock bosh midrange power was huge also 3 more miles to the gallon
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Melting Slicks
Joined: Apr 2002
Posts: 3,019
Likes: 0
From: down that one road next to that big tree
Re: Bosch Platinum 4 Plugs (cesar)
i wonder if voltage is what's behind the problems here. i have a msd blaster 2 in my car & 6t box, i've ran the +4's and also the normals & just love em. however i wonder if the +4 takes more current to operate since it has 4 tabs? it's just a wild guess but why in the world would they work so well on higher output cars & just suck on cheap cars?
Le Mans Master
Joined: Apr 2000
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From: DrunkDefender
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Re: Bosch Platinum 4 Plugs (gtsyellow)
This comes up from time to time. I say the stock ac delcos are beter than any +4 plug out there. People replace old plugs with new +4s and its the fact that the plugs are new that makes the difference. I honestly believe the +4 are snake oil. The electricity is going to take the path of least resistance and will therefore only fire from 1 of the 4 electrodes at one time, the other 3 are just in the way. Stick with the stockers.
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Re: Bosch Platinum 4 Plugs (red90sixspeed)
This comes up from time to time. I say the stock ac delcos are beter than any +4 plug out there. People replace old plugs with new +4s and its the fact that the plugs are new that makes the difference. I honestly believe the +4 are snake oil. The electricity is going to take the path of least resistance and will therefore only fire from 1 of the 4 electrodes at one time, the other 3 are just in the way. Stick with the stockers.
For the Probe, I suspect the stock coil does not generate sufficient voltage for the gaps on the +4.
Thread Starter
Racer
Joined: Jun 2002
Posts: 428
Likes: 0
From: Dallas Tx
Re: Bosch Platinum 4 Plugs (Mez)
Thanks for all the feedback. Sounds like I should stick with my cut-back single electrode Platinums.
BTW, I agree on the Probe thoughts. Most Boschs come gapped a little wide (0.045). This is great for a spark, but requires a coil and wires that are in top notch shape or you get misfire under load from the increased voltage requirements.
BTW, I agree on the Probe thoughts. Most Boschs come gapped a little wide (0.045). This is great for a spark, but requires a coil and wires that are in top notch shape or you get misfire under load from the increased voltage requirements.