HKS S/C modification
 

Hi everyone

I wanted to start this new Thread because i'm about starting a new project with consist on modifying the HKS S/C for 86/ BRZ

Currently my car makes up to 202 WHP with the F-con computer provided by HKS , and to be honest i don't see much difference running with it or without it


I got the idea after i came across this video on youtube

[ame="http://www.youtube.com/watch?v=lwIilncWpG8"]http://www.youtube.com/watch?v=lwIilncWpG8[/ame]

basically i have HKS S/C installed on my BRZ , but the way the guys from HKS installed the S/C on their car is quiet different to the regular one (check below for both setups)

Regular setup :
http://image.motortrend.com/f/featur...r-engine-3.jpg

HKS Setup :
http://www.vividracing.com/catalog/w...2001-AT008.jpg

So basically the differences are:
-The position of the supercharger it self which is flipped 90 deg to the right , also
-The size on the pipes they using are a way bigger then the regular setup
- Bigger Inter cooler
- Air intake position is Under the Front bumper

So I believe the HKS setup will produce more Power and torque and better engine response than the Regular setup.

First Because they using larger pipes which means that more Air is pumped into the engine , which is proven by HKS themselves (Check this link Below) to increase the S/C using a different pipes sizes.
http://www.hks-power.co.jp/en/produc...g/rt_img01.gif

http://www.hks-power.co.jp/en/produc...estrictor.html

Second is the way the air goes from the Air intake to the to the engine is shorter

So i think doing the same think on my car will definitely give more HP and TQ
but i will need to Tune my ECU for the new setup , which is not an issue as I already have the OFT and just waiting for the guys from Vishnu tuning to send me the particular tune for my car

I Will appreciate any advises or feedback from you guys , on how to setup and the size of the pipes i will need to get it done

do you allready have the HKS SC kit? otherwise i'd go with the craftwerks..

Well i already have the Kit installed for almost two month now !

its very possible the HKS setup is a prototype, and the one available commercially is optimized for mass production. If you already plan to get rid of their computer, just go with a different computer and get a custom tune. I'm sure that will yield a lot more power than trying to mimic the original setup.

That's exactly what i'm doing right now.

I've got the OFT and just waiting for the tune file , after that I will do a few Dyno sessions to see the difference between the OFT tune and the F con
attached are the results I've got so far using the F con , which is very limited for tuning

I've heard that using the same supercharger , removing the retraction plan that come with the s/c will yield up to 400 Hp , but for this i will need to upgrade my injectors and the fuel pomp as well

The setup on the HKS car I believe the compressor position is right on where the air conditioning unit is.. So I guess you would have to sacrifice the A/C if you want this setup.

Yes you're right , but i can't sacrifice the A/C as i live in a hot area , which means you can't drive with out A/C most of the time.

so basically what i want to do is change the pipes size , and the Air intake position which goes under the front bumper

The graph is not reflecting changes in pipe sizes, it is showing the results with different size inlet restrictors.

Restrictors are a way to limit boost, while keeping a small pulley size to maintain decent mid-range torque.

sooo....even though there is a restrictor...and that is the limiting factor, and you know this and posted graphs about it, you still want to not do any of what your post was about, except change piping sizes...which you admittedly know aren't going to make more power, because there is a restrictor (not to mention a throttle body)

what is this thread about?

EDIT: hahaha didn't realize the OP didn't see that the chart was of restrictor sizes

I don't get this, sending a tune is different from actually tuning your car. Who is going to tune your car?

Well what's the point of changing the inlet size if you are using small pipes to pump air to the compressor
So changing the pipes will involve the intake inlet size as well

As for the restrictor plat it does limit the the boost , but in order to remove that you will need to upgrade a lot of parts on your engine

The size of the pulley size does effect directly the compressor boost and the engine out put , and the one comes with the HKS S/C is pretty big

I'm considering to change the pulley as well

The thread is about the modifying the original setup for the s/c , and the reason I posted this here is getting people to give me their opinions and advises , as I'm not an expert , and I'm looking for some help if you don't mind that , and I think that the whole idea why people creating forums

As for restrictor chart it shows that changing the size will change the the s/c out put , so if you are looking for a small increase of hp and tq you can change the size , and if you want go higher then you just remove the restrictor

Well then lets straighten out a couple things.

1. changing your piping diameter WILL NOT net you any additional power, your throttle body is already smaller than the tube Diameter

2. Shortening the length of piping in the system will increase the response (or decrease lag if you prefer) of the system, Increasing the diameter will actually do the opposite, hurting response.

3. Restrictors in the intake side of a compressor will limit the max flow through the compressor and provide a constant HP curve with a decreasing TQ curve once max flow is reached (HKS's graph is BS but it almost shows this trend) see how the curves match closely until they diverge, that shows the varying choke flow of each restrictor.

Pulley size changes in conjunction with restrictors will only change the "spool up" of the supercharger, since ultimate flow is limited by the restrictor.

Make sure you know what the multiplication ratios are and what the max SC RPM limit is before you go changing too much on the pulley size,

Right so if I understand you would recommend to shorten the piping length with out changing the pipes size

As for replacing the pulley will need some calculation in order to find the right size

Here are some information in relation to the compressor

Max rpm 110,000 rpm
Max pressure. 2.5
Max flu ratio 22 m3/m
Power rage.200～400 ps,
Drive unit ratio 9.444

Attached is the equation on how to calculate the ratio

What are your thoughts for the pulley size ,

with the regular pulley the extra power torque comes really late after 4800 rpm

So in order to use the extra power you get from the supercharger you always need to push the car hard for higher rpm
Would be better is can get that power a little bit early