Custom tune on M4 w/ 20k miles... change spark plugs?

[Steve B.]

My local custom tuner is recommending spark plug and coil pack change (my car has 20k miles, its a 2015, before tuning. I only plan to keep the car as long as it takes for the new M3 to come out. Can I get away without this additional ~$600 job?

[wsccsw13]

Recommend interval is every 25k miles; their life expectancy is markedly shortened by a tune.

[r0wr]

I would just wait until you need to change them. I recently changed my spark plugs after running a tune as the OEM ones crapped out after about 15k hard driven miles. I recommend upgrading to NGKs.

[FriedPiston]

No point in going custom tune if you're going to question your tuner's recommendations. The car has plenty of power in stock form, you can try to learn how to drive her fast as is.

Consider getting a catback exhaust to trick the brain into thinking you're going fast like you have some sort of custom tune.

[Steve B.]

Originally Posted by nars3000

No point in going custom tune if you're going to question your tuner's recommendations. The car has plenty of power in stock form, you can try to learn how to drive her fast as is.

Consider getting a catback exhaust to trick the brain into thinking you're going fast like you have some sort of custom tune.

I have a 911 Turbo to go fast. The M4 is my quick, precise DD. Thanks for rec though, makes sense as this isn't the first M4 he has done.

For the record, he told me to replace plugs and coils at 30k, but I figured its a "while im there" type of job.

[FriedPiston]

Originally Posted by Steve B.

I have a 911 Turbo to go fast. The M4 is my quick, precise DD. Thanks for rec though, makes sense as this isn't the first M4 he has done.

For the record, he told me to replace plugs and coils at 30k, but I figured its a "while im there" type of job.

Cool! Is it a 996 or 997? and how fast exactly? 600whp Cobb tuned fast, or upgraded turbos with PI fast?

NGK 97506 fapped to 0.018" is a must for 500+ whp on the S55. Coil packs don't need to be replaced until they actually start misfiring. They are likely 100% fine with only 20k miles on them.

If you have access to full E85 and have an active BM3 license, the secret to going fast (without paying for a custom tune) is by loading BMS' free full E85 BEF on stock boost. This will put you roughly at 520-530 whp between 18-20 lbs of factory boost.

The same free E85 BEF can also transform your daily driver M4 easily into a 10-second car when equipped with a properly configured JB4 unit.

Best of luck!

P.S. pun intended on the spark plug gap.

[Steve B.]

Originally Posted by nars3000

Cool! Is it a 996 or 997? and how fast exactly? 600whp Cobb tuned fast, or upgraded turbos with PI fast?

NGK 97506 fapped to 0.018" is a must for 500+ whp on the S55. Coil packs don't need to be replaced until they actually start misfiring. They are likely 100% fine with only 20k miles on them.

If you have access to full E85 and have an active BM3 license, the secret to going fast (without paying for a custom tune) is by loading BMS' free full E85 BEF on stock boost. This will put you roughly at 520-530 whp between 18-20 lbs of factory boost.

The same free E85 BEF can also transform your daily driver M4 easily into a 10-second car when equipped with a properly configured JB4 unit.

Best of luck!

P.S. pun intended on the spark plug gap.

Its a 996TT. Its far from stock, GT2 bumper, HREs, Bilstein Coilovers, custom interior, etc... but as for power I just did a Speedtech X-pipe with 200 cell cats and a Softronic tune. Now has 500hp/533tq... more than enough for me. I run out of road really quick.

Thanks for the pointers...