CSL airbox vs throttle response/low rpm torque

[Gt4]

I know everyone here loves their CSL airbox cause it looks so good in the engine bay and THAT sound at high RPM.

I don’t have a lot of experience with M3 with CSL airbox. I have a Karbonius CSL airbox for 1.5 years now and still not installed…

I had a Geoff Steel CSL intake in the past on a track car with TTFS tune and honestly didn’t liked it. Also had a lightweight flywheel and other mods on that car. It feels slow to me (torqueless at low RPM) and always tought it was the tune…

Last week, I was working on a car with a Turner CSL airbox. Went for a road test. Car feels like there is no throttle response, sucks especially when you are use to a certain amount of pressure on gaz pedal to rev match on downshift. I never drive on Sport mode. Tried it on Sport mode and it was still bad.

Anyway, not sure I like the CSL airbox modification after driving that car.

My question is: is this something normal with all CSL airbox that doesn’t have a motorized flap or is it due to a bad tune?

[ZiMMie]

Let me guess the car was running an alpha N based tune?

A proper CSL Map based tune does not have this effect. it contrary the opposite very direct.

[Slideways]

9 times out of 10, it is a poorly calibrated tune. What tune was on the car that had the Turner box?

Having compared a TTFS tune with the stock CSL tune, there were some very questionable modifications to say the least.

The main goal of the airbox is reduce the restriction at the mid and top end. The low end should stay the same due to the velocity stacks being identical between the stock and CSL airbox. Turner might be a little different due to the trumpet design, but it won't be by much.

[Gt4]

Let me guess the car was running an alpha N based tune?

A proper CSL Map based tune does not have this effect. it contrary the opposite very direct.

My TTFS tune was a CSL tune with TTFS modified air rail.

The car last week has an Alpha-N tune.

Good to know that it’s probably tune related. I will install mine soon and plan to do remote dyno tune with HTE!

[Gt4]

9 times out of 10, it is a poorly calibrated tune. What tune was on the car that had the Turner box?

Having compared a TTFS tune with the stock CSL tune, there were some very questionable modifications to say the least.

The main goal of the airbox is reduce the restriction at the mid and top end. The low end should stay the same due to the velocity stacks being identical between the stock and CSL airbox. Turner might be a little different due to the trumpet design, but it won't be by much.

The car with the Turner airbox has a local guy random Alpha-N tune… haha

[Slideways]

The car with the Turner airbox has a local guy random Alpha-N tune… haha

Even with a pre-calibrated tune (not even dyno) from HTE or PCS, it should be a completely different experience.

[lemoose]

When spending nearly of $3k on the total cost of this mod, i cant understand why anyone wouldnt just suck up the extra 10-20% added cost to do it properly with a MAP- especially with all the stories like this.

[SQ13]

Let me guess the car was running an alpha N based tune?

A proper CSL Map based tune does not have this effect. it contrary the opposite very direct.

The Alpha-N tune on my silver car works just fine. Blue car, not so much - hesitation when rev matching under ~3k RPMs. Both HTE tuned.

[stephen]

My HTE alpha N tune bogs on rev match downshifts unless you heel toe. Hasn't bothered me enough to fix but I would like to do a MAP sensor conversion. Good to know that should fix it.

[Sprp85]

Tried both HTE and PCS off the shelf tunes for stock US Spec vehicle + Karb box with MAP configuration.

PCS knocked it out of the park for me, in terms of stock-MAF like experience. Smooth everywhere, no wonkyness at all.

[Tbonem3]

My throttle response is great, evolve alpha n tune from 2017. Car is an explosive beast.

[Tbonem3]

When spending nearly of $3k on the total cost of this mod, i cant understand why anyone wouldnt just suck up the extra 10-20% added cost to do it properly with a MAP- especially with all the stories like this.

Didn't need to.

[usdmej]

My question is: is this something normal with all CSL airbox that doesn’t have a motorized flap or is it due to a bad tune?

around 5 years ago it was very commonplace, the old M3F had a huge thread about it with issues ranging from just poor throttle response/hesitation to the "bucking bronco" effect

it seems like with time, ECU tuning has resolved a lot of people's issues, but there are still probably a lot of people driving around with subpar driveability thinking it's a good enough tradeoff for the airbox sound

[tlow98]

My throttle response is great, evolve alpha n tune from 2017. Car is an explosive beast.

fwiw, my experience was the opposite with evolve + alpha N. Boggy, and mostly just felt slow to respond all over. CSL tune and map sensor improved it, but then I had a low rpm bucking/stutter.

this was back in 2014 tho. Sounds like tunes have come a long way since the.

[chapmans]

I have an evolve airbox, PCS tune, light flywheel, 288 cams and my engine blipping and low speed throttle is still way worse than my 987 Boxster S. It's always baffled me why it isn't better