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Compression test


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Good morning, I"m a newbie and sorry if this has been addressed before..(im sure it has) I have a Compression test on 7/3 and was wanting to know the questions i should ask the shop while im there? Also im going to have them do spark plugs and coil packs and was wanting to know the most tried and true Plugs/wires/coil packs? Thank you so much in advance!
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A leak down test is typical along with a compression check.

 

We have no wires and no need to replace the coils unless you're having misfires.

 

I run NGK 2309s one step colder but if I remember correctly 6418s are the stock heat range. Good idea to replace the plugs at the same time, buy them in advance and have the shop install them.

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No real questions, they should know what they are doing.

 

One step colder plugs are normally cheaper and work fine. I have used them since 60,000 miles in my wagon.

 

Agree coil packs should be fine. Still have the ones that came on the car.

 

What town do you live in ?

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Again, I've had one broken clip since 60,000 miles. a zip tie will fix it. You may be able to see it in one of the pictures in my click here link in my sig.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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i herd the clips on the coil packs break easily and im sure @155,000 mine are pretty brittle...Thats the only reason i really want to do them...Are the coils usually good for the life of the car?

Unfortunately, the clips that break aren't on the coils, they're on the harness. No biggie, zip ties hold fine.

 

Why are you getting a compression test?

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Unfortunately, the clips that break aren't on the coils, they're on the harness. No biggie, zip ties hold fine.

 

Why are you getting a compression test?

It's a new car (to me anyway) and just going threw the list of things to check before I put any mods on...Besides the exhaust that just I had to get...

 

Sent from my 0PJA2 using Tapatalk

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Do not use one step colder plugs unless you are tuned for them. Use the stock heat range NGK 7913 SILFR6A. Compression and leak down tests should be run together. Compression should be 140+ across the board with less than 10% leakdown.
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Coil packs usually last for many years. If one begins to go out, you will begin to get misfires that will throw a CEL. No real benefit to replacing them with another version that claims to improve performance or has a pretty girl in the advertising. :lol:

 

Colder plugs just get fouled up sooner unless you actually need them. I guess all the cool kids have them for some reason.

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Coil packs usually last for many years. If one begins to go out, you will begin to get misfires that will throw a CEL. No real benefit to replacing them with another version that claims to improve performance or has a pretty girl in the advertising. :lol:

 

Colder plugs just get fouled up sooner unless you actually need them. I guess all the cool kids have them for some reason.

 

All the cool kids buy colder plugs because they are less money. Or is that all the cheap kids...;)

 

I thought I read somewhere the OP is getting a tune...? Or am I confusing him with another...

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Do not use one step colder plugs unless you are tuned for them. Use the stock heat range NGK 7913 SILFR6A. Compression and leak down tests should be run together. Compression should be 140+ across the board with less than 10% leakdown.

Thanks gex! Now at least I know what to expect for results.... Is stage 2 tuned enough for colder plugs?

 

Sent from my 0PJA2 using Tapatalk

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The reason I ask is that I had my car in recently for a compression test and while they were in there they changed the plugs just as a preventative thing. They mentioned though that the plugs that were in there (came installed on the car) were not the correct plugs. My logic was that since I've been etuned by TA, on the wrong plugs, then theoretically with the right plugs, the tune is now not right.

 

All that being said though, I'm about to install a couple other parts and get retuned anyway.

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Guy's, I have been running one step colder plugs since, 60,000 miles, which was before Mike (TA) had tuned my car. Talk with your tuner.

 

They make the tuners job a little easier to tune with. I have not seen any ill effects from them in well over 180,000 miles with them.

 

FWIW, I put the Perrin panel air filter in at 2000 miles, went Cobb AP stage 1 at 8000 miles.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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If the spark plugs you have are actually causing a problem, then colder plugs would make sense. People saying "my car runs smoother" or "I feel more power" are usually experiencing the placebo effect, like the "hot coils" and other automotive sugar pills. But by all means, do what you like.
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If the spark plugs you have are actually causing a problem, then colder plugs would make sense. People saying "my car runs smoother" or "I feel more power" are usually experiencing the placebo effect, like the "hot coils" and other automotive sugar pills. But by all means, do what you like.

 

 

Have to agree, the plugs won't make any difference that you'll feel.

 

Unless like the last time, I waited until I got a CEL for a misfire before I had the plugs replaced. They had over 80,000 miles on them. A new set of one step colder, made a big difference then. ;)

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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...Unless like the last time, I waited until I got a CEL for a misfire before I had the plugs replaced. They had over 80,000 miles on them. A new set of one step colder, made a big difference then. ;)
I did my first set around 55K miles, just because they were about due and was surprised they still looked pretty good. Probably could have waited. The idle seemed to improve a bit.
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I did my first set around 55K miles, just because they were about due and was surprised they still looked pretty good. Probably could have waited. The idle seemed to improve a bit.

 

I'm sure was from the placebo effect...LOL ;)

 

Both my cars change idle speeds depending on a number of different things it seems.

 

The wagon has started to get a low idle sometimes when in line leaving work in the parking lot on a hot day with the AC on MAX, and I'm going between 1st gear, moving a car length, push in the clutch back into neutral, then repeat to move 15 feet... over and over again for about 500 feet. If I rev the engine after a few times of that idle comes back up.

 

Hey the cars 13 y/o...

 

The Spec B will have a high idle when I push in the clutch and coast the last 1/2 mile to the off ramp from the highway. It returns to a normal idle at the stop light.

 

The wagon will always go to 850-900rpm where Mike set it when I coast for long ways. Which I do a lot.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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They foul up easier.

 

From RallySportDirect a large aftermarket Subaru supplier.

 

Q:All i have is a catback . can i still use this even though my car is stock?

 

A: We do not recommend running these plugs for your application. A general rule of thumb is about every 100-150whp over stock, go one step colder. It would be best to talk with your tuner to see what works best with your setup.

 

 

FWIW my built motor car with a dom1.5xt-r turbo runs one step colder plugs. My stage 2 ots tuned car runs stock heat range SILFR6A plugs.

 

But like I said. Do whatever you want. It's your car.

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