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DO NOT use bosch 4+ plat plugs!!!!!!!!!!!!!!


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okay people, i have verified the wether or not to use the bosch 4+ plugs. i read a few " i dont like them" and "they didnt work in my other car so i dont use them in my subie" threads but never a 1st hand expererience. the car im refering to is a stock drivetrain '86er GL wagon 4X, with a factory subie carb on it so there arent any other "improvements" to get confused with. ive had the plugs in the car for about a month and a half but havent done any long distance driving. short trips or doin a little wheelin, i did sense a lttle hesitation on some RPMs but notheing drastic. i simply thought the carb was out of tune since the motor and carb came from a donor "85 from idaho that had been sitting since '97. my fiance and i shipped out to idaho this last weekend and on the way over, at about moses lake, the high end power seemed like it wasnt there anymore. throttle: spotty. no acceleration from 3- 4000 RPMs. slowed down to the shoulder, revved it a couple times, let it cool off for literaly 2 minutes, then she ran and idled fine. perplexing. from then on, every 10 miles or so it would do the same thing. let it cool down, she ran fine. so i pulled into spokane, picked op some NGK V-powers from schucks, threw them in and drove the rest of the way to Rathdrum ID. NO PROBLEMS TO SPEAK OF. BTW, the 4+ plugs looked kind of deiseled so i would say that was the problem. drove home on sunday, didnt drop below 75 MPH the whole way home. most of the time i was passing at 80. the entire RPM range seemes like it ran with less stress and ran cleaner. take it from me, bosch 4+ plugs SUCK!! im gonna see if i can send them back to bosch to get some $ back since they were expensive. hope this helps someone choosing??

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Another problem with the bosch plugs is that they like to cease up, so when you go to remove the plugs you end up removing some of the cylinder head with them. Ain't life grand

Well, all you'd have to do is re-tap, bore and stroke new spark plug holes. Then the displacement of the spark plug would increase so a bigger Bosch spark plug could be used. We all know a bigger spark equals more power from a more complete combustion. :brow::rolleyes:

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Hate to be the fly in the ointment here guys but I've used the platinum fours and they worked great. Better idle, better off the line . The motor is still running strong, no problems. I've heard a lot of people here put them down, and I'm not offering any hard proof or trying to be a PITA, just offering a dissenting view. Matt.

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"Most" any plug works fine if it is used correctly. Some engines are designed to run hotter and the Bosch plugs are designed to run hot. Suby engines generally run cooler thus needing a cooler plug; otherwise you can get misfires and hesitation. NGK's run cooler and are less prone to seize up. Though when dealing with an aluminum block I would always use anti-seize lubricant on the threads.

 

-Mike

 

 

Hate to be the fly in the ointment here guys but I've used the platinum fours and they worked great. Better idle, better off the line . The motor is still running strong, no problems. I've heard a lot of people here put them down, and I'm not offering any hard proof or trying to be a PITA, just offering a dissenting view. Matt.
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One good reason not to use Bosch is that the German metric thread pattern has a different pitch. Perhaps that's why they appear to "seize up". The amount of distance for the electricity to jump is therefore greater than it is supposed to be (or is it less? I'm soooo confused! :-\ :confused: )

 

NGK is the best for Subarus. NipponDenso is also good and usually a bit less expensive.

 

Emily

http://www.ccrengines.com

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I had Bosch Platinums (just regular platinums, not the fancy ones) in my turbo wagon for a while. Didn't really notice any performance difference between them and ngk's, delco's or any other cheap brand.

 

The only thing was that I had to re-gap the platinum plugs sooner, as the electrode seemed to disappear a little faster than a standard plug.

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I had Bosch Platinums (just regular platinums, not the fancy ones) in my turbo wagon for a while. Didn't really notice any performance difference between them and ngk's, delco's or any other cheap brand.

 

The only thing was that I had to re-gap the platinum plugs sooner, as the electrode seemed to disappear a little faster than a standard plug.

hmm... your not supposed to gap the platinum plugs.

 

electrode disapear? like due to being the wrong heat rage for the car? a bit too hot

NGK and Delco are not "cheap" brands they both make good quality plugs.

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hmm... your not supposed to gap the platinum plugs.

 

electrode disapear? like due to being the wrong heat rage for the car? a bit too hot

NGK and Delco are not "cheap" brands they both make good quality plugs.

 

Regapping the platinum plugs kept them running a lot longer than if I hadn't done it. At the recommendation of my parts guy, I went one range cooler with the platimums, and the electrode wear wasn't too quick. I just didn't notice any improvement in performance over 'standard' plugs.

 

As for "cheap", I was talking about the price compared to platinum or irridium plugs, at least for how much I pay for them. I use ngks on my cars.

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Hate to be the fly in the ointment here guys but I've used the platinum fours and they worked great. Better idle, better off the line . The motor is still running strong, no problems. I've heard a lot of people here put them down, and I'm not offering any hard proof or trying to be a PITA, just offering a dissenting view. Matt.

how long have you had the car on the road at one time? mine only started really acting up after the motor got nice and hot. if you havent had some long distance driving done in the car (4-8 hours at one time) then i would say you havent seen the problem yet........

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Well, I drove it from Denver to Iowa and back a number of times, then I gave it to a kid who has been driving it ever since. He's taken it to Nebraska at least three times that I know of and drives it to school every day. I know for a fact that those same plugs are still in it. I keep after him to change them but it's a miracle when I can get him to change the oil, let alone anything else. Matt.

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Regapping the platinum plugs kept them running a lot longer than if I hadn't done it. At the recommendation of my parts guy, I went one range cooler with the platimums, and the electrode wear wasn't too quick. I just didn't notice any improvement in performance over 'standard' plugs.

 

As for "cheap", I was talking about the price compared to platinum or irridium plugs, at least for how much I pay for them. I use ngks on my cars.

the reason you dont gap platium plugs is the gap tool usually damages the tiny little platnum tip. at least thats what the Bosh rep. told us back when I used to work in parts.

 

the problem with regaping is it does not take into consideration the wear on the internal resistor. usualy if the tip is worn to the point where the it needs to be regaped the resistor is worn the same.

 

I understand you did not mean cheap like crappy but I just wanted to clarify for others reading this thread that although they cost less they are probably the best plug to use in our situation.

 

your parts guy was wise in cautioning you to go colder with a bosh plat plug. he must have known about bosh generalizing the needed heat ranges for specific motors.

yep I use NGK too.;)

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I use Bosch Platniums. The ones that are 1.99 a piece. I've had no problems with them, and I've put 10,000 miles on them. Several 400 mile trips. I've got them running in the Brat that I sold to my roommate and he hasnt had any problems with them either. The heat range thing is nice to know about. I think I'm gonna go get a set of colder plugs.

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