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Flash, keep us posted as your kit develops. A lot of folks (me included) would like 300 or so at the crank without massive mods to include intercoolers and what not.

I see one of two outcomes for this:



1) My wife castrates me with a dull, rusty butterknife

2) My wife re-enacts the "The Burning Bed"



Nothing good will come of this potential development... MARK MY WORDS PEOPLE!



<img src="/forum/images/smilies/968/laugh.gif" class="smilie" alt="" />

[quote name='flash' post='58509' date='Aug 28 2008, 09:02 AM']one thing to remember, this is not something that will ever be "cheap" - the hardwre and plumbing to make this work right will take some time, and won't be simple



if you are the type to buy used parts because you either can't or don't want to spend the money on new ones, this is NOT for you - there will be no shortcuts[/quote]





[quote name='biotechee' post='58543' date='Aug 28 2008, 12:09 PM']I see one of two outcomes for this:



1) My wife castrates me with a dull, rusty butterknife

2) My wife re-enacts the "The Burning Bed"



Nothing good will come of this potential development... MARK MY WORDS PEOPLE!



<img src="/forum/images/smilies/968/laugh.gif" class="smilie" alt="" />[/quote]





Thinking back to my last 2 service visits at IMA, I think the SC will be cheap in comparison. It's thing like that kills a marriage.

[quote name='flash' post='58497' date='Aug 28 2008, 10:17 AM']we are looking to do about 270 at the wheels - that's it - any more than that and you start having a lot of issues with suspension, chassis, etc[/quote]



Doesn't the full spate of enhancements you can potentially do to a normally aspirated engine - air box mod, RS Barn Stage 3 chip, RS Barn headers & cat back, and possibly RS Barn cams and their stealth ITB program <img src="/forum/images/smilies/968/biggrin.gif" class="smilie" alt="" /> have the capability of bringing the rear wheel HP close to this level? Does this mean suspension mods would be needed for a set-up like this?

while it might be able to be close, streetability becomes an issue when you get up that high in normal aspiration - suspension mods need to be done in stock trim, let alone with any power mods - the more power, the more brakes and suspension

Hi



I emailed SFS reference info about running problems etc, they now say the driveablity is sorted see there reply below



The early kits that used a custom DME chip were sort of hit and miss as far as idleing and drivability.Now that we switched to the Super-AFC fuel controller a few years ago.the diel and drivability is outstanding.



What everyones take on this, has anyone fitted the kit with this new system



Cheers



Simon

[quote name='ordy' post='58727' date='Sep 1 2008, 04:18 AM']Hi



I emailed SFS reference info about running problems etc, they now say the driveablity is sorted see there reply below



The early kits that used a custom DME chip were sort of hit and miss as far as idleing and drivability.Now that we switched to the Super-AFC fuel controller a few years ago.the diel and drivability is outstanding.



What everyones take on this, has anyone fitted the kit with this new system



Cheers



Simon[/quote]

do the new s-afc's allow for timing control? Back when I was into doing turbo hondas, a lot of people used s-afc's for tuning... with very bad results. It allows for low resolution fuel map manipulation, but no timing control... something that is very very very bad for forced induction.





That said, I've been out of the loop for a while, and haven't checked out any of the safc products in some time. This may have changed by now.

Hi



I dont know how it works, i think i will wait and see what flash comes up with as there SFS bhp does not seem worth the risk, there kit is rated 310bhp, dont know if thats at the wheels or flywheel.



There is to many maybes with the kit.



Cheers



Simon

The SFR kit is rated at the wheels.

The APEXi Neo is a Piggy Back system that's hocked up in the stock wiring loom of a car. It usually takes rpm over the ignition signal, load over trottle position and some other values if needed / wanted. It gives the user the possibility to change the AFM-signal - which is taken over the PB - as a function of rpm and load up to about +/- 50%. Doing so the ECU will in- or decrease the amount of fuel being injected as it "thinks" more or less air mass is being aspirated. In some cars this will indirectly also change the timing as the ECU is running in lower or higher areas in the ignition maps due to the changed AFM-signal. This is because "load" is in some vehicles consisting of air mass flowing and trottle position.

If an ECU workes like this lowering the AFM-singal will usually lead to more ignition advance and altering the AFM-signal will lead to less ignition advance.



I made some testing with my 968 during the last few weeks using the vitesseracing PB ( http://www.vitesseracing.com/html/piggyback.html ) which is basicly a Perfectpower SMT6 unit. This unit is much more sofisticated than a APEXi even though it basicly works the same. The unit also uses an ignition ampifier that allowes to alter and retard ignition timing.

I my special case I use a 3-Bar-MAP-Sensor (0-5V) as "load" for the PB which in my eyes seems to be perfect when changing to a Supercharger; the changes made to the fueling (over AFM-Signal) is then a function of rpm and manifold pressure...



As I had to tune the car on the big injectors (as a preparation for the SFR SC instal) I realiced that changing the AFM signal would not affect the timing (messured with the Bosch hammer) at least not in the areas I changed the values which was from about 4.85V to 4.50V.



As my mechanic will start to implant the SC tomorrow I will probably be able to report some more first hand experiances soon; concerning power / drivability and whatever.

If we dont get to the point by using the Vitesse unit we will reprogram the ECU...

Kunz,

Good info.

Please keep the progress of tuning updated.



Thanks!

this seems to point out that, since you are playing with something where you don't know the outcome, that the "kit" is either still not "complete" or you have chosen to go another route - i'm curious - which was it?

I always like to get out the max; efficency, power, flexebility ... and - as some might guess - I like to do things on my own.

I cry tears of frustration thinking I can't instal the SC on my own (due to a lack of time) after all I have done myself now to the car...

And still I am sure that there are not many things that can't be done better...



After some experiances with different models of APEXi fuel computer on my long-gone Mazda and on my 968 (conversion to E85 in last summer) I am sure if some of the parts are selected and sized properly (in this case the injectors) the SFR-Kit could work more or less like a "plug'n'play". Remember, the APEXi is preprogrammed to let the car run pretty rich at WOT. So most probably after installing everything the car would run nicly with no issues.



But I have no idea if it is all close to that "max" I want to reach. I dont know how much room there is left concerning knocking / ignition. And last summer I still had some issues to get the correct rpm-reading from the ignition signal with the APEXi. Maybe this could have been solved by placing some resistors, anyway, it still didnt satisfy my personal needs.



So i have chosen to take a unit with more possebilities like the VitesseRacing PB. It gives me access to fueling and ignition... and I can do that on my own with the laptop on my knees, on the run or at home in the livingroom. I can brain-out some new idea during the night, program while the family is still asleep in the morning and test on the way to work. Driving home I test the next version.

Something very essential for tuning is the possibility of logging. The VRPB can do that. So I just drive on different load levels across the revs and then analyse everything while parking somewhere.

I find it a bit unfortunat to always keep an eye for example on the AFR at WOT...



Still the VRPB has it's limitations: As long as the engine runs in closed loop (and this is the case up to very high loads) there is no chance to change fueling because the ECU will make the car run at 14.7 AFR. So even using big injectors, the ECU will correct in a wide range the fueling to 14.7. But these corrrections are then also taken for the WOT / open loop which is not what you really want. What you can do with the VRPB in this area is to set the corrections of the AFM-signal such that the ECU itself doesnt have to correct to get to 14.7...

Easily said, but you try a bit I tell you!



For me the SFR Kit is a great basis to start from; I dont have to produce all the brackets, piping and whatever more which would be a BIG thing to to. This is enough for me, I can do the rest...

High compression motor + horribly thermally inefficient pump + no intercooler + no ignition control = recipe for disaster...



this is what makes me really nervous about these set ups without knowing more about what's being done to keep fueling, egt's, and ignition in check.





why are people so eager to do set ups without intercoolers?

Hi Saxman



The SFR-kit uses an IC, if needed I will install a Waterinjection to supress detonation...

[quote name='Kunz' post='58810' date='Sep 2 2008, 01:12 PM']Hi Saxman



The SFR-kit uses an IC, if needed I will install a Waterinjection to supress detonation...[/quote]

was somewhat half discussing yours and half discussing the kit the flash was talking about on the previous page.



Honestly, I think water injection is a bad idea... not that it doesn't work, but that I wouldn't want to have the safety of my motor relying on a consumable. Just takes that one leaky hose or time to forget to check it and you're shopping for a new block.



It really shouldn't be needed on a modest set up with a good intercooler and proper tuning. This is a situation where the adiabatic efficiency of superchargers really shows its evil side, and why I'm very much partial to turbos.

intercoolers are NOT necessary at low boost levels on a centrifugal supercharger - they add much less heat than a turbo - as long as you keep it down to 5lbs or so, it's absolutely fine - 6-7 is "OK" but anything from 8 on up and it is a MUST - in fact, at lower boost levels, and intercooler actually REDUCES the efficiency of the supercharger - that is one of the main reasons i do not plan to do anything over 5 lbs



as a rule:



a roots type makes 18.5 degrees of intake increase per pound of boost

a screw type makes 14.6 degrees of intake temp increase per pound of boost

a centrifugal unit makes only 13.6 degrees of intake temp increase per pound

a turbo will make about 25 degrees of intake temp increase per pound (can be more, depending on unit)



as we measured a 30 degree drop by merely moving the intake point, a little quick math and you will find that a centrifugal unit, with the intake point moved to the grill, results in only 38 degrees of intake temp increase net - not enough to worry about



yes, a turbo is MUCH more efficient, and can make a LOT more power - however, at low boost levels, a centrifugal supercharger is the easiest and least expensive way to get power



it really all comes down to the goal

where are you getting these numbers from? superchargers typically show MUCH higher temp increases than turbos... thats part of the reason turbos are so much better. I would love to see evidence to the contrary

lol - known this stuff for years, but try google - i found it pretty quickly, but it's all over the place - there is even math to figure it out if you are so inclined



the heat of superchargers is only generated from the compression of the intake air



the hear of a turbocharger starts off with air that is well over 300 degrees hotter and then compresses that



pretty basic stuff

Are gases getting mixed up here? A turbo doesn't compress gas that is over 300 degrees hotter (which I take to be a reference to exhaust gas); the turbo is driven by that hot gas so that it can compress the much cooler intake gas (air).