MrGone

iTrader: (30)

Here is some spark plug info for VG's and VE's

Here is a chart from NGK's site showing you what the plug numbers and letters mean:
http://ngk.com/images/NGKsparkplugNum.gif

FSM pages stating the proper plug/heatranges for our cars
VG:
http://digitalbeta.net/images/FSM/VG%20Plugs.JPG
VE:
http://digitalbeta.net/images/FSM/VE%20Plugs.JPG

Things to know
The VG's stock heatrange is 5, the same as the VE. (not 6 like alot of people think)
VE's come with Platinum plugs stock, VG's come with Copper plugs stock
I prefer the V-power copper plugs from NGK for both engines. You will get the best performance, cheaper at the expense of shorter plug life (15k vs 60K)

The standard copper electrode NGK plugs are BKR5ES-11's
The V-power copper electrode NGK plugs are BKR5E-11's

Heat Ranges:
Read up here before you decide to run a hotter, or more commonly a colder plug:
http://ngk.com/charglossary.asp?kw=Heat+range

For NGK plugs, a larger heat range number means a colder plug. For Example:
BKR4E-11 = 1 step hotter than stock
BKR5E-11 = stock heatrange
BKR6E-11 = 1 step colder than stock


Spark Plug indexing:
This practice is making the grounds face the same direction in each cylinder. Generally you want to point the ground towards the intake valve(s) which helps prevent blowout and also (in theory) keep the flame in the direction of the exhaust valves instead of the intake valves. Of course there might be 1 or 2 people making enough power that they notice effect from this. (those people, if they are even reading this are only reading to try and pick me for mistakes )

Thats all I can think of for now

internetautomar

iTrader: (30)

that is not NGK's website, it is owned by a place called monarch distributing.
NGK's website is www.ngksparkplugs.com

Their tech page http://www.ngksparkplugs.com/techinf...000&country=US

yes NGK gave their "ok" to monarch having the site though

AH11980

Hey everyone
quick question , i own a 1991 maxima, with 134000 miles on it , and i was wondering if its a good idea to slap in the BOSCH Platinum4 in it. I just want the best for my baby. Thanks in advance this is a great site

P.S Ill post some pics soon of my Maxi

mtcookson

iTrader: (2)

bosch plugs tend to not work the greatest on most import engines. stick with NGK for these cars.

blackandwhite

iTrader: (3)

Well...the plats for the VE cost 4~4.5 times what the coppers cost, and last 4 times as long....the coppers may save A LITTLE money in the long run, but the plats save labor....even if it's your own.

Cliff Clavin

iTrader: (11)

I think with cars this old and usually over 100k miles on the engine, it is to your advantage to change or check the plugs a lot more often than if the car and engine were new. There is no advantage in labor if you are going to check (remove) the plugs every 10-20k miles. I don't think on any car with over 100k miles I would just throw in a set of platinum plugs and ignore them for 60k miles.

If the car was brand new, I would stick with platinum, but being my car is so old (just like the rest of the 3rd gen owners), I just put in coppers and replace them when I check it.

AH11980

Cool thanks for the input. I was wondering what to choose.Plus NGK are cheaper than BOSCH

Thanks a bunch

TempMaxMan

Torque Specs for the plugs, please. Rethreading would suck, of course.

TempMaxMan

I hate bumping, but I really do need the torque specs ASAP. Please, post them up and post your source for the specs ASAP.

89blackse

iTrader: (2)

30-40 guesstamate pounds. I know for my VG i guess got them hand tight and then turned them till they were firm and solid but not thread stripping tight.

Source: My Dad/lazyness

TempMaxMan

No way! At least I HIGHLY doubt it and would be surprised. 30-40 ft lbs is A LOT AS IN TOO MUCH for spark plugs IMO. Thanks for the effort though.

I think about 5 ft lbs is estimated to be what is done when you screw something so it is flush/flat with the object it is penetrating and then you turn it 1/4 turn. But, this is totally a guess and there is plenty of room for misinterpretation and error. It's best to use a torque wrench.

The maximum I've seen spark plug torque specs to be is about 20 ft lbs. I suppose most are within +/- 5 ft lbs of 20 ft lbs. But, just a lb or two off and you could need to re thread, which can be described as one of the worst jobs ever.

I was especially concerned about the VE30DE engine specs when I saw this thread about re threading the head: http://forums.maxima.org/showthread....=1#post4114549

I really want the OEM specs. I'll call NISSAN tomorrow if I have to.

89blackse

iTrader: (2)

Just a joke yo. Being sarcastic. But yeah I would call Nissan if no one chimes in with better information.

TempMaxMan

Suuuuuuuuuuuuuurrrre.

But, like I said in my above edit. Thanks for the effort.

Greeny

iTrader: (43)

10-12 ft/lbs...

Note: if you strip your heads...I ain't my fault...

I just do the "thats feels good to me" method..

89blackse

iTrader: (2)

I think the biggest scare should be crossthreading. I like to turn them anti-clockwise till they 'click' then start turning clockwise and 99% of the time you get them in the right way.
Then do the MrGreen method...

Cliff Clavin

iTrader: (11)

Ask Jeff92SE

Greeny

iTrader: (43)

Fixed.....

TimberJon

iTrader: (2)

I use the NGK Iridium IXs. I buy them imported. Gap them once at .045 and torque them to 19.6 ft. lbs. I own a VE, and NGK says the recommended ft. lbs should be anywhere from 18.0 - 21.6 ft. lbs.

If you torque them to 18, you will notice a difference in mileage than 19, and so on. The distance the spark hovers within the chamber from the thread point is critical. Also, it doesnt matter if you have a V on the reciever, or two recievers, or four. Its all about the power of the spark, not if there are two or more of em. You can test the power of the spark by unplugging one of your electrical plugs from your engine and plugging it into your new plug and watching the spark. The brighter the better. Use a welding mask to actually SEE the shape and structure of the spark, and play around with the gap. Fix it to where the structure is not too thin and not too thick, and doesnt disperse at the reciever too much.

elusivemax93

i put in bosch platinum 4's yesterday and torque recommendation for those are 21 lb/ft

TempMaxMan

Thanks for the replies.

The way you word it sound like you're only concerned with the plug thread stripping.

The thing to be most concerned about is stripping the threads in the head.

I was amazed to find Torque Specs and Gap Specs in the user manual.

Lists the torque spec range as 14-22 ft lbs. I'm thinking I'll go with 20 right now unless somebody or myself convinces me otherwise.

You mentioned mileage difference due to torque specs. Makes sense, though I imagine the difference to be small. What to you think is best for best fuel economy/mpg? Think 20 ft lbs is good?

Lists gap at .039 - .043 inches or 1 - 1.1 mm.

Specs are for both VG and VE engines.
I'm working on a VG30E.

elusivemax93

im just stating the torque specs on the bosch box. i didnt have a torque wrench so i only torqued them down to as good as i could by hand

TempMaxMan

That's cool. Just reminding you and any other person reading that it's more important to be concerned with the torque specs for the head that the plug is going in to.

BTW/JFYI; I just picked up some Champion copper plugs from Advance Auto for $1.7x .
Gap is listed at 0.044 , about right on the large side according to the manual for the car at .043.
No torque specs listed for the plug.

TimberJon

iTrader: (2)

Absolutely correct on the head threads. Dont screw those up. Punn intended.

For our thread size, the gap should be .044 or +/- .001.
Like I said, I used about 19.6 foots and gained an extra 20-30 miles per tank. I used to have it at 21, thinking that Id torque it really close to the maximum recommendation and It wont come loose over time and will be very secure and sealed..

When you think about it technically. The combustion of the bang works better inside the engine when the spark goes off closer to the outside wall, than towards the center of the chamber. So the closer to the wall your spark is, the better the bang. Its all about timing and the differences are so minute that damnit, we just cant tell.. But my miles per tank tells a little story..

RULE OF THUMB FOR TORQUEING!! (spelling?)

Tighten the bastard til it is as hand-tight as your naked hands can get it, without the ratchet, just the extension and socket. Then apply enough force with your ratchet/socket combo to turn 1 revolution. Try for 2/3 a turn or 3/4 first. You want to turn it lightly until it resists a moderate emount of pressure. DO NOT immediately place your hand at the very end of the handle and spin it around a few times. Works fine for lug nuts, not your plugs. That is usually to-spec torque without having a torque wrench handy.

Oh, and when you remove your plugs, do it while your engine is cold please. And use a nylon or brass bristle brush and comb the threads down in the head if you can. Might have to use a pair of needle noses to hold the bristle brush. Important to try to clean up any loose deposits of old anti-seize or grit. Ever been in wood shop? Teach tells you to sand with the grain? Brush with the threads, not against them. Clean the brush off for each thread port. Theres usually leaves and pine needles and crap down near the plug ports, try to vacuum all that crap out before you even take the plugs out. You dont want ANYTHING falling in there.

Jeff92se

iTrader: (82)

Oh you two are funny. f-u-n-n-y!

It screwed in FINE. Just decided to blow out on day on the freeway! aieeeee!

rmdl51

iTrader: (4)

Hey there! I was one of the bosch plat +4 users till now that im reading this thread, so want to change my spark plug to NGK but I dont know which ones, I already check the site but it comes with 6 options, standard, G power, G power platinum, Laser iridium, OE laser iridium and Iridium IX, is this last one the very best? I'm not sure, I jus want the best for my Maxima. Thank you!

TempMaxMan

Ha!

Are you talking about when you had to rethread the head?
Seem like you are. In that case .... wowzers ... that sucks and is quite interesting. Do you know how many ft lbs you had the plugs torqued in at the time?

TempMaxMan

Platinums are what manufacturers usually use. They fire okay, and last extremely long (maybe 60k miles). They are usually 4-5 $ a plug.

Coppers are what I like to use. They fire well and last about 10-15k miles, which is a good time to check up on plugs and wires and everything else anyways. They are also very cheap at 1-2 $ a plug.

Iridiums are considered to be the best firing plugs. I don't know what the longevity is supposed to be like. They usually cost around 8-10 $ a plug.

I just got Champion Coppers for about $1.78 a plug. I'll probably gap them at .044 and torque them down to 20 ft lbs.



***Thanks for the reply, TimberJon

internetautomar

iTrader: (30)

you have a 1990 which is a VG30E, the factory put in plain old coppers
http://www.internetautosupply.com/ca...roducts_id=369
1.80 a pop right there

Jeff92se

iTrader: (82)

Yup. I don't know what the torque values were. I know I gave them a good torquing. You can't go overboard anyway. As the head and threads are aluminum.

I still have the special tools if anyone would like them.

Chris Gregg

iTrader: (59)

I checked out NGK's site and they have the VG plug listed as heat range of 6. This is versus the VE listed range of 5. So, maybe I'm confused, are you saying that stock VG's came with 5's or just should have 5's? Then why does NGK recommend a one step colder plug (6)? Please clarify.

NGK also recommends a heat range of 6 for VG30ET as well. Which I thought was interesting. I'm actually running 8's right now and knew it was too cold. I've got some 7's I'm going to throw in and see the difference.

internetautomar

iTrader: (30)

from the 94 FSM

TempMaxMan

I got this Champion Copper Plus part#: rc12yc

Stock #: 71

http://www.championsparkplugs.com/mo...AAIA=&pid=8491

Part of me thinks I should have gone with the NGK and confirmed heat range. I was in a rush though and don't think I even saw any NGKs.
The old plugs I pulled were NGK BKR5ES.

The Champions I got seem to be doing well. Good power.
I don't know what the heat range is for the plug though and I am very curious.
Gapped them to .044 .

I got them for about 1.78 a plug at Advance Auto.

internetautomar

iTrader: (30)

Champinon's generic import plug.
they sell it for 75% of the imports out there.

TempMaxMan

It'd be great if somebody knew the heat range for it. Do you?

internetautomar

iTrader: (30)

the 12 is the heat range.

TempMaxMan

Holy crap. Are you telling me that "heat range" numbers are standard/universal AND that heat range numbers are "colder" the higher the number is AND that the stock plugs used for the maxima are a fairly "hot" heat range rating of 5 and the FSM says you can even go as hot as a 4?

Please reply asap. If this 12 rating is accurate and on the same scale as heat ratings shown on the NGK plugs and listed in the FSM then I am getting new spark plugs and it'd be nice to pick them up this evening.

How do you know for sure that the 12 in the prt number is the heat rating and that this is on the same scale as the numbers on the NGKs?

TempMaxMan

You think I'd have any problems going with the #4 heat range with a VG30?
Seems the FSM lists a 5 as standard for the VG AND VE yet the VE lists a 4 as okay to run "hot" but does not list the same "hot option" for the VG. Seems to me that they are similar enough engines to be able to accept the same plugs in stock form.

internetautomar

iTrader: (30)

there is no "universal" heat range, all the companies do it a little different
just for example
91 max
ACdelco is a #1 heat range
Motorcraft a #2
NGK a #6
Denso is a #2 or 20
Autolite is a # 03
Bosch is a #7

as you can see there is no real logic persee to the heat range versus # across brands. you can only compare them within brands

internetautomar

iTrader: (30)

why would you want to run a hotter plug?
are you fouling out?

TempMaxMan

I see. And if you knew the comparison of NGK to these Champions then I'm sure you'd have listed it.

Logic would say that IF BOTH Champion and Advance have their stuff together then the Champion heat range of 12 would at least be the equivalent to NGK's 5 ... since they listed this as a good plug for the Maxima with the VG30. But, companies aren't always as correct as they should be.

Firstly, it seems logical to me that on a mostly very well running stock engine setup ... that maximum octane from gas and maximum heat range on a plug ... while still in the efficiency range for the engine ... is best for best performance. It should help for the best burn. Best burn should = best performance.

I am getting an intermittent miss. Some times it sound like there is 1 cylinder not firing at all, sometimes there is no miss and clearly all are firing ... and sometimes it's a mix of both ... with faint intermittent/off beat missing.

I am also seeing some sort of fluid drip from near the throttle body. The exact location that the fluid is leaking from is not yet identified, but it seems to be on a lower hose from the TB to the IACV-AAC. I currently don't imagine it being anything other than fuel. It drips more after high revs.

I'm thinking and injector is bad and or fuel is not being burnt due to cold plugs. I have not yet had a chance to pull the wires on the plugs with the engine running while it is also consistantly missing.

The engine is putting out enough power to spin tires a bit from a dead stop out of 1st gear selected with a VG30 and auto combo. But, it's obviously not running as well as it should be.

I'm thinking it would be worth it to just eat some humble pie and go get some NGKs. Seems like it'd be best to go with 4s and not 5s. Your thoughts?