Is that the case with a 2.3L?

 

No, in any case.

I have 2.0 stock engine with HKS 274/278 and HKS 7460, and 2.3 (ultimate rotating assembly, built Buschur head/intake/TB), with S2 and BBK-B.
On E85 mild tune 2.0 makes 395whp at 28psi and in track tune 2.3 at 28 psi makes 425whp.
Mustang, same dyno.
There is more: the 2.0 has JIC with 2.5" neck down at the CAT, and it runs a CAT!!!! And Tomei downpipe (70mm OD 65mm ID).
The 2.3 is full 3" with straight pipe.. And the downpipe is customized MAP with full 3"...bla bla.


HKS VS BBK-B = +40whp as a rule of thumb, on E85.
And of course timing has a lot of effect on power, but also can lead to issues...so they are both mildly tuned, with the 2.3 perhaps being milder than 2.0 by a hair. Its track tune.


To finish off, based on my experience, in the top end its the turbo that makes most difference, and cams have mild effect - unless you are at 700whp GT42 turbo or something.

Clearly, I gained ~30whp and that can frankly be totally attributed to the BBK-B.
The displacement, +300ccm, makes seems like no particular difference at top end. It does make a difference at the bottom, it spools the -B like 2.0 spools a 2.3 and puts by default torque +40wt or so above 2.0 below 3000rpm.

So, yes, I am skeptical of the benefits of S2 over HKS in real world, and I can tell you from experience that on an Evo 8 (no mivec) making S2 idle decently is a little challenging, and the off idle behavior is nowhere near as "smooth" as HKS cams. Its racy, it reminds me of the old-schoo hot rods that are a bit temperamental.

So I would love to see back to back comparison to see if me going back to HKS cams would hinder my output.

I am also skeptical of effects of the 2.5" neck downs at the cat typical of JDM exhausts: on the same 2.3 I had Apexi Noir which is necked down...and frankly my butt dyno cannot tell the difference!
Wonder if any can be measured. Maybe at 500-600whp on Mustang, maybe, but at 425whp to me it feels the same.

 

Managed to get some track time with the bbk

 

What laptimes do you run on thunderbolt?

 

My best time was 1:32

 

looking good Sam. didn't know you got new turbo. were you running 400+ whp on KHC dyno is very strong. was that the HP you were running at TB?

 

I went with the BBK early last year after the flapper on my HKS warped. I haven't really driven the car much since and this was my first track event in over a year. I just don't have the time and the car doesn't have proper safety equipment to be pushed close to 10/10th.

I'm still @ full weight 3,450 w/driver and no cage. I was running the lower boost map, around 24psi and 245 nittos. It was cold in the morning 30f and warmed up to 50f later on. This event was a last minute decision, signed up the night before.

The car has a lot more power than I have ***** lol. I'm throwing a lot of time in turns 2, 3, 5, 6 and especially the last turn before the main straight, but it's OK, going home with the car still in one piece is is also rewarding.

 

^ I know someone with an autopower roll bar for sale if you want to step up your safety.

 

autopower rear cage sitting at the shop

Thanks for running BBK-

cb

 

So dyno curves aside, as its evident even in the Dynojet Vs Mustang dyno curves you posted, the load and even how the dyno operates affect readings.

How do you feel the car pulls on at 2000-3000rpm on BBK-B versus HKS?
Do you miss low end torque with -B over HKS?

On the dyno there is a huge difference in low end torque: is that evident on the street?

I would not turn boost higher than 22-23psi on track.
Most experienced tuners of track-race cars will advise to stay down at 21psi, up to 23psi perhaps, but no higher.
25 minutes of full throttle is hard on the motor.

 

my stock turbo doesn't even pull all that great from 2k-3k in nay gear except 1st or 2nd. Why are we even concerned with power down there? Downshift...

 

Because not all places in the world are completely flat for miles in all directions like Las Vegas.

 

Thanks, I will think about it. But in the back of my mind, at this point, I might as well go with a full cage, no?


The BBK needs to be above 3krpm for anything useful to happened, the HKS 2700-2800rpm (from what I remember). Mid-range, both feel about the same. While the HKS feels OK at top rpm, the BBK feels stronger and more consistent. For example, on track, the HKS would pull fine the first couple of laps, but it seemed to lose steam near the end of a long straight, where the BBK doesn't.

 

What's that supposed to mean? And vegas isn't flat. the section of freeway I take to work every day has a 1/2 mile long 6-7% grade. Several other spots in the valley are somewhat hilly.


Regardless of that, downshift.

 

In my case HKS has nice drive and torque already at 2,000rpm, making 4psi down low.
It quickly spools to about 8psi by 2500rpm, so you can say part throttle torque is awesome and better than stock.

My concern is that -B on 2.0 lags far more than HKS.

On the other hand -B on 2.3 is amazing:
Strong Drive from 2000(5 psi), ramps to 10psi by 2500rpm even at part throttle if enough load.
So it's like driving LSx V8.
But on 2.0...I guess unlikely.