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Discussion Starter · #21 ·
Well, it still hates 87 when the AC's on (yup, I expected as much, just wanted to test it). Initial throttle bog/tip-in from a stoplight is now instantaneous - no huge lag like before, but it starts jerking a little between 1800-2500 RPM when the turbo picks up.

However, with the last tank of premium in hot weather, it was smooth sailing throughout the entire RPM range.

Blk88verde, what are your impressions?
 

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Being on 93 premium (since I am tuned) - all good, zero lag/hesitation with A/C on. I have been away for a few days and took wife's CR-V, so I have not had a chance to further test with more load in the car etc. But like I said on initial impression, these plugs are an excellent improvement over a known route that has previously caused lag/hesitation with A/C on (highest setting) with the stock plugs. As you noted improvement through entire rpm range - my car pulls stronger and smoother up thru 5000 rpms over stock plugs. When I get back home I will be able to further evaluate and report back in.
 

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Probably put 150 miles on the new plugs this week end. Still running real good. Zero hesitation /lag w/AC running. Seems to hold speed on long hills better in top gear than with the iridium's. Temps in low to mid 80s and humidity 80 to 90 %.
 

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Discussion Starter · #24 · (Edited)
Probably put 150 miles on the new plugs this week end. Still running real good. Zero hesitation /lag w/AC running. Seems to hold speed on long hills better in top gear than with the iridium's. Temps in low to mid 80s and humidity 80 to 90 %.
Awesome...mods, can we move this to the 1.4 tech section? I think this is a worthy "upgrade" for power delivery with the 1.4 turbo.
 

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I will be doing a 500+ mile road trip starting on Wednesday evening and returning Sunday evening - I will provide another update following my return.
 

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Well, it still hates 87 when the AC's on (yup, I expected as much, just wanted to test it). Initial throttle bog/tip-in from a stoplight is now instantaneous - no huge lag like before, but it starts jerking a little between 1800-2500 RPM when the turbo picks up.

However, with the last tank of premium in hot weather, it was smooth sailing throughout the entire RPM range.
I had to use AC on my way back to Ottawa yesterday. It wasn't too hot (mid-70's) but it was probably clost to 100% humidity a lot of the way. We drove through some pretty crazy downpours.

Anyway, with the AC on and 91 in the tank, even accelerating easily I noticed some "uneven" acceleration starting somewhere around 1700 RPM. Maybe the high humidity had something to do with it (probably did), but I was surprised to feel it none the less. I wonder if the engine mapping changes as soon as the AC is engaged? I've been driving with the same 91 V-Power gas for the last few tanks and felt nothing in the way of hesitation.

For the record I'm not tuned and I have my gaps set to .038" and my plug resistors removed and replaced with all-thread to lower the ignition circuit resistance.

I may just order a set of those coppers and try them out... for $10 it can't hurt.
 

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Discussion Starter · #28 ·
I had to use AC on my way back to Ottawa yesterday. It wasn't too hot (mid-70's) but it was probably clost to 100% humidity a lot of the way. We drove through some pretty crazy downpours.

Anyway, with the AC on and 91 in the tank, even accelerating easily I noticed some "uneven" acceleration starting somewhere around 1700 RPM. Maybe the high humidity had something to do with it (probably did), but I was surprised to feel it none the less. I wonder if the engine mapping changes as soon as the AC is engaged? I've been driving with the same 91 V-Power gas for the last few tanks and felt nothing in the way of hesitation.

For the record I'm not tuned and I have my gaps set to .038" and my plug resistors removed and replaced with all-thread to lower the ignition circuit resistance.

I may just order a set of those coppers and try them out... for $10 it can't hurt.
Even without AC, I felt that jumping at low RPMs at times. Iridiums were @ .032, haven't removed the resistors. I now feel it on 87 oct., but nothing on 89 and above.

My guess would be that the engine just runs with a lot more load on it at low RPMs with the AC running, meaning it's running into more knock @ low RPM. The compressor sure does affect how hard the engine seems to have to run at idle.
 

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The compressor sure does affect how hard the engine seems to have to run at idle.
Agreed 100%... I can barely tell the engine is running at idle, but with the AC on it's definitely working a LOT harder, there's some very obvious tactile feedback coming through the driver's seat, and this was with the fan at setting 1. The car seems very efficient cruising with the fan on setting 1. The fuel economy impact was less than I expected.
 

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So you put in these? Going to pick up a set then. Probably why I get hesitation all the time.

NGK 4644 BKR7E Nickel Spark Plug
SKU: #BKR7E
ITEM: # NGK4644
BRAND: NGK
 

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My old ep civic came with iridiums stock. I swapped them for coppers cuz they were cheaper. The car drove fine but i lost 20whp on the dyno and they fouled out after a few weeks. If anything just swap to 1 heat range cooler iridium than stock. This is what srt4 and terminator cobra owners do, even on a completely stock car.
 

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Discussion Starter · #34 · (Edited)
My old ep civic came with iridiums stock. I swapped them for coppers cuz they were cheaper. The car drove fine but i lost 20whp on the dyno and they fouled out after a few weeks
You were clearly running the wrong gap/heat range for that application. I've run them on a Honda D-series with no problem at all.

Titan, I wouldn't expect more than a 25-30,000 mile lifespan. Thats a year or two of driving for me, which I am fine with. Gap on the low side - the gap will widen with time.



Sent from AutoGuide.com App
 

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If anything just swap to 1 heat range cooler iridium than stock. This is what srt4 and terminator cobra owners do, even on a completely stock car.
Based on this:

http://www.cruzetalk.com/forum/34-1-4l-turbo/9634-ngk-plugs.html#post138469

GM may have already gone one heat range colder in early 2012. Maybe another step in that direction is in order? I've been wondering about this for some time... it's about the only thing that makes sense as to why a plug would cause knock.
 

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Discussion Starter · #36 ·

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Interesting...mine were a 7 though.
Yeah, I've got the 7's in mine as well. Interesting note on the OEM plug:

[NGK-Iridium-IFR7X7G] - - It's Free! : NGK Spark Plugs Store!, NGK Spark Plugs We Sale, Spark Plug For Racing car, Automobile, Motorcycles, ATVS, Scooters, Marine Engine, Agricultural Equipment

Notice how it specifies a "Copper Core Ground Electrode"? I wonder if that, combined with the colder 7 heat range, are intended to keep the plug from being a point of ignition? The original IFR6Z7G has the same "G" designation depicting this feature (I assume anyway since it doesn't show up anymore).

If a colder "8" heat range IS worth something on this motor, this plug is available with a starting gap of .044":

[NGK-BKR8E-11] - - It's Free! : NGK Spark Plugs Store!, NGK Spark Plugs We Sale, Spark Plug For Racing car, Automobile, Motorcycles, ATVS, Scooters, Marine Engine, Agricultural Equipment

Maybe for the guys running tuned? If .044" is too large it could always be closed up a bit. The stock plugs spec at +/-.008", so those could be closed down to .036" if the spec is the same?
 

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You were clearly running the wrong gap/heat range for that application. I've run them on a Honda B-series with no problem at all.

Titan, I wouldn't expect more than a 25-30,000 mile lifespan. Thats a year or two of driving for me, which I am fine with. Gap on the low side - the gap will widen with time.



Sent from AutoGuide.com App

K series is way different than b series. B series come with coppers and k series come with iridium cuz of cop ignition. The coppers will never burn as stong and consistant as the plugs were intended on this car under stress.
 

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Yup, that's them!
Ok so I'm definitely in as well. Sounds like a great idea. On my non-tuned Eco what gap do you think I should run on these BKR7E plugs?
 

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Ok so I'm definitely in as well. Sounds like a great idea. On my non-tuned Eco what gap do you think I should run on these BKR7E plugs?
You could probably set them to .032" and check them periodically, say every six months or so? They are old school plugs and the gap will widen with time. You could run them at .035" like most are doing with the stock iridiums but you'll have to keep a closer eye on them WRT wear.
 
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