The problem with that is that most industry standard cars HP numbers are based on dynojet numbers. Reliable or not, its the chosen model.

 

Cosworth,
What you have is sort of where it all began. The RS Tuning program that goes past 1.0 is pushing over 540ps with K24's, a 5bar FPR, exhaust and air filter. I would guess you are running a solid 550ps+.

ps is close enough to hp. Just a tad more conservative.

 

I have a K24 setup from AWE. I've never dyo'd my car, but AWE shows the following on a Mustang Dyno: Baseline of 355HP for a stock car and 503HP for a car a car with the K24 setup on 93 Octane.

I considered 24/18s but will likely never put race gas in my car so I felt the incremental increase in performance on pump would not be worth it.

 

reading some forums i've the idea that there are oppesed opinions about 5 Bar Fpr essentiality from US Tuners vs European Tuners...I mean , the only one that use 5 Bar in Europe is Fvd with K24/26...All the other like RUF , 9FF , Rs -tuning etc. don't use it at least for applications in order of 550 - 600 Hp.
Please consider that when my tuner (from Rs-tuning company) estimate to me K24/26 conversion for sustained 1.2 Bar , he never speak to me about the necessary of 5 Bar..
Sure European tuners has the tendency to stay more conservative that US tuners about boost levels and Hp unless you don't go for radical and most expensive mods so i think that when more fuel is really needed Europeans directly goes for upgraded injectors and/or fuel pump.
I don't know what is the right way to go but sure if RUF and Rs Tuning says you can boost 1.2 bar on K26's without 5 Bar ,i think that my 1.1 - 1.2 on straight K24s with most reason should be ok with A/F ratio and injectors duty cycle.

If i'm really at 550 BHP i'm very happy

 

as far i've seen on some tuner sites flashed k24 including 5 bar and free flow exhaust good for about 530 hp, others saying 550 hp. I didn't dyno my car yet but is night and day

 

from what i know if you are using race gas all the time then that would be fine. if you are on pump gas, yes your car will run and run fine until you blow your engine... more gas, injectors, 5 bar = safety. i went with injectors not only for safety, but the response is insane..... very quick car on 1.1 bar pump gas... note: i will only run 1.3-4 with my race file, thats race gas... i don't think your close to 550 hp.. 480-500 most likely!!! thats moving

 

I use only European pump 100 octan fuel like SHELL V-Power 100 and i hope this is enough..i don't know how much US octan correspond Europe 100...occasionally i also use pump Europe 95 that shoul correspond to your US 91...but sure when use it i don't drive the car harder ...maybe i use it only for long highway trip to go to the beach with girlfriend

 

If you are present when the tuner does your flash file, you will see they all have to work on keeping the AFR to hold steady with stock injectors and stock FPR (if you want safe AFR rather than max power), given you have moved your rpm limiter to 7100-ish. If you're at stock rev limiter I believe the injectors are still able to keep up decent.

However, the injector duty cycle at full rpm at only 1.0 bar with K16 (not even K24) is already above 95% with stock FPR at 7000rpm and up there the injectors usually lose precision. With 5bar FPR you get the injectors into a slightly more linear range where they could also give a touch margin.

5bar FPR is a dirt cheap way to get more margin for safety. It's not ideal bc it's not as accurate of a solution as adding better injectors, but they do add margin. It's not very hard to install either.

 

Comment on dyno numbers:
Dynojets for talking actual power levels is like using slow watches to measure laptimes...
Sure I can do a 6-minute lap at the Nurburgring Nordschleife anytime with a stock 996TT, just give me a "Dynojet stopwatch"!

(they should start selling that but I'll take a percentage per sold item)

 

Actual power numbers are a myth imo because no one except manufacturers really know engine HP and that changes once you mod the car. A good dynojet number can tell you just as much about your car as a good mustang dyno. As mentioned on a daily basis dynos should primarily be used for baseline and deltas anyways because actual power can be argued forever.

 

So i risk to run out of fuel when pushing my car at WOT to 7k rpms ?..even using 100 Ron Shell V-power ?
So how can RUF and Rs-tuning use Hybrid K24/26 boosting 1.2 mantein a decent A/F ratio with stock injectors and stock FPR ?
I don't belive that a Tuner like RUF make run his cars lean with risk of broken engine..

 

I don't know, maybe they run 98-100% duty cycle and leaner AFR and feel happy doing that. You should ask them. I do roadracing and live a long time between 5500-7100 rpm, often 35-40 deg C in summer track days and need a AFR to keep engine cool on 1.1-1.2 bar boost. If I did the odd power run maybe I would be ok with leaner AFR and maybe that's what they do. I added a 5bar FPR and my tuner had no problem to make the ECU hold the AFR to revlimiter.

 

Absolutely!!

Can not be said any better than this.
Not sure why people don't understand this.

 

Hi,Just to add here.....I know FVD use to do alot of K24/26 turbo upgrades and they always had a 5bar included in there tuning map/ kit for them......

 

Yes John you're right .. if you take a look at one of mine previous posts in this topic , i also said that FVD (sure in my knowledge) is the only one in Europe that use 5 Bar for K24/26 conversion..But RUF and Rs-tuning don't use it.
In any case if the tuned MAP works accordly with Knock sensor , does not the ECU retard timing to prevent any engine damage if A/F ratio become too lean ?