924srr27l

It would be interesting to see some power / torque figures from this?, I think different cams have also been fitted.


My Engine builder Races a 3.0 968 N/A which currently is producing 330bhp !


R

Ish_944

I think numbers will be available once the kit will be marketed. I reckon you can already get one if you contact him but it's not yet in the webshop.

Raceboy

Lol, that was my intention: to point out that most old school engine builders know basically nothing about modern engine management systems and always tell you that stock is better. Because they don't know how to tune it.
There's still big number of people who think that Motronic is the best system ever created and it should be worshipped. If it is such a good system, why Bosch developed more advanced systems then
Nothin else to add. You stick with your 205 hp, and I'll stick with my 500+ hp 924.

924srr27l

For your Information Racerboy, the Mapper tunes Modern Road & Race cars, working with many sophisticated modern Programmable ECU's etc...


500hp+ is a fair figure for an N/A Amazing........!


Whoooooosh......


R

Raceboy

I think you should learn to read first. Funny how mnay times I have to correct spelling mistakes for native english speakers (ie. brake vs break, their vs there, Raceboy vs Racerboy etc).

I am happy for your mapper but your statements are just as valid as someone saying he has been in space or something. He can tune but obviously does not know how to tune or something if he says that standalones cannot be mapped as good as 30+ year old AFM system. Duh.

924srr27l

I can read your rudeness perfectly, you can run along now...

924srr27l

I must if missed this post.......




"The MAF and MAP setups are so much superior in PART-THROTTLE, CRUISING power to the AFM it's hard to believe"
How and Why are they superior ?
You've seen the two graphs right which show the Superior bhp and Tirque my car has compared to Augments Map system ?


Part throttle is very crisp and pulls lik a Train with my AFM set up...


I bet you don't have 190 ft lb's @ 2800 rpm ?


"You keep going back to your belief that the AFM is superior...I have said that it can flow pretty darn well as long as you are at FULL THROTTLE and at high rpm, when the flapper door is wide open"
That's Not exactly my line Nope...as I've explained how many times, my engineers explained the AFm and all stock system live mapped would be the best solution for road / street use...


I always said I want low and mid range torque, good throttle response and driveability (Torque) low down at the expense of a Top Line Figure..


But in the end I got the lot !


I've done over 600 miles so far, and I've not gone Full throttle Yet!


There's like no need or reason to go anywhere near this!


It's like riding a big 1300cc Japanese Motorcycle, the torque is so full
from tickover, I'm changing gear at 3000rpm and using hardly any more than just over half throttle...so your "Illusion" that my AFM has to be at Full Throttle to flow well is well .....really not the case and then some!






"But at less than ~4500rpm and at part throttle the flap is mostly closed, meaning your 2.7L engine is breathing through only a sliver of air pathway rather than the full 50x50mm square bore. Naturally this will cause choking at PART THROTTLE low/medium RPM operation"


Your having a Giraffe ! Below 4500Rpm ??? Try below 2500rpm and she pulls like a train..below 4500 she going to the moon and after this it's in Orbit... !


Natural Choking ?... Your Joking !


I am also "a tuning novice compared" to the experts....


And this is how it will stay for me, I have a vested interest in many avenues of a car but on some subjects and complicated components, it's best to stick with the people that know what they are doing through success and years of experience....


R

924srr27l

I was hoping to add up the total cost of their entire system as fitted to the 911& Porsche world's Editor's Car, but everything is not on the webshop like the AFM delete pipe & Filter box etc.....?


He also had a Full rebuild including Steel Liners, so we must be well over £5000 total fitted, installed, mapped etc...?


This is obviously a lot compared to buying a chip off Ebay !


His car was not 163bhp before but did go from 144 to 175, so a 31bhp gain but my engine is only 228cc more but 30bhp more than this and most importantly all on Stock 924S2.5 Bosch equipment....


That's gotta make some people consider about spending this large amount on aftermarket ECU / wasted Spark, Injectors, Camshft & AFM & Distributor Delete etc...etc...



R

V2Rocket

It is superior because I have been daily-driving this setup for over 3 years now. I drove with the stock DME/AFM for 8 years before that and the difference in all around cruising power, passing power, and WOT blast is night and day.

The AFM is VERY GOOD but the MAF/MAP is just better!
The AFM lets the car run very smooth but the MAF/MAP runs smoother!

No, I have about 165 ftlbs at 3000rpm because I have a low-compression 2.5L with the mildest of 944 cams, with a mild tune, running mild petrol.


This is not some figure I made up, Giraffe or not...that is a factual figure based on testing of AFMs (earliest by BMW folks) and the design criteria set forth by BOSCH when they invented the damn thing!

Think about how the AFM works...it has a spring-loaded flapper door running on a potentiometer track, to measure airflow based on the "vacuum signal" coming via the throttle plate. Low throttle position = low airflow means the door is sitting mostly CLOSED. Higher throttle, more airflow, more AFM flapper opening. At a certain point there is sufficient airflow to defeat the spring entirely and the flapper whacks wide open, but at that point the AFM is NO LONGER MEASURING ANY INCOMING AIRFLOW AT ALL, instead the DME is taking a wild guess as to air-fuel ratio based on pre-programmed information (displacement of engine vs RPM)

No amount of DME tuning will get over that physical fact! You can adjust the internal spring somewhat to richen/lean the mixture out, but not very much.

You want to stick with people with years of experience, but then when people who aren't your personal acquaintances come through with YEARS of their own experience you disregard them entirely? User Raceboy builds aftermarket ECU's for Porsches and other marques (recently a Ferrari!) to eliminate the obsolete AFM-based system and unlock real performance. Even the most mild of tunes produces incredible results purely because the engine CAN NOW BREATHE...

I don't know what it is with you and some of the other UK-based Porsche owners out there...but you sure are a stubborn bunch!

924srr27l

[QUOTE]
It is superior because I have been daily-driving this setup for over 3 years now. I drove with the stock DME/AFM for 8 years before that and the difference in all around cruising power, passing power, and WOT blast is night and day.
oh..... do you have before and after graphs? or do they not really illustrate this night and day passing power?


If only you were in the UK, you could of had your stock ECU & AFM system live mapped....!




I've thought about how the AFM works from your description....


Low throttle position - low airflow
Higher throttle - more airflow


This sounds very good, like a variable inlet system?


But the descriptions about having to defeat a spring, and wild guessing , not to mention no facility to NO LONGER MEASURE ANY INCOMING AIRFOW AT ALL sounds just terrible ! I'm surprised this engine even runs !


MY engine must have some sort of Special flapper system and some really good guessing calculations as it's pretty Kool!


how the AFM works...it has a spring-loaded flapper door running on a potentiometer track, to measure airflow based on the "vacuum signal" coming via the throttle plate. Low throttle position = low airflow means the door is sitting mostly CLOSED. Higher throttle, more airflow, more AFM flapper opening. At a certain point there is sufficient airflow to defeat the spring entirely and the flapper whacks wide open, but at that point the AFM is NO LONGER MEASURING ANY INCOMING AIRFLOW AT ALL, instead the DME is taking a wild guess as to air-fuel ratio based on pre-programmed information (displacement of engine vs RPM)






I don't know what it is with you and some of the other UK-based Porsche owners out there...but you sure are a stubborn bunch!


Anyone that wants to be a successful race driver or a F1 ENGINEER? You need to come the UK we're very good.....



British F1 drivers have kicked butt Racing in the USA, vive versa has never worked too well, Haas is having a go at F1 with a car that's part Ferrari designed by people from the UK !


R

V2Rocket

Here you go.
Red is mild-tune MAF on mild-petrol (91AKI) + 2* advanced stock camshaft...Blue is stock DME/AFM.
These figures are measured at the wheels.
This is on a dyno so of course is done at WOT. But I assure you, the gains are just as great at part throttle.
I have not yet dyno'd my MAP setup, but intend to do so back-to-back with/without an AFM installed in the intake tract (installed but not plugged in) to measure the real restriction it poses...that should make us both happy

Quote:

I've thought about how the AFM works from your description....
Low throttle position - low airflow
Higher throttle - more airflow
This sounds very good, like a variable inlet system?

No, not even close.
Think about drinking through a straw, but pinching the straw between your fingers vs letting it sit "fully" open...you won't get as much beverage through the straw for the same given "suction" with the pinch!

Quote:

But the descriptions about having to defeat a spring, and wild guessing , not to mention no facility to NO LONGER MEASURE ANY INCOMING AIRFOW AT ALL sounds just terrible ! I'm surprised this engine even runs !
MY engine must have some sort of Special flapper system and some really good guessing calculations as it's pretty Kool!

The DME still *works* by guessing the AFR. But it is not very accurate guessing - that is probably a lot of the reason your "on dyno Live tuning" worked out so well - the DME defaults RICH RICH RICH at high RPM past the "flapper door wide open" point so that it runs safer than risking going lean with high timing advance at 6k rpm...

But if you watch a stock 944 (at least US spec) on the dyno floor it, you can see puffs of black smoke coming out the tail pipe when it hits this default-rich zone!

Quote:

Anyone that wants to be a successful race driver or a F1 ENGINEER? You need to come the UK we're very good.....

DOn't know...don't watch F1. I like LeMans better, where the cars look like cars and there aren't any politics to placate a 300-year old Elton John-lookalike (Bernie)

jhowell371

Air flow is air flow, the barn door at part throttle does restrict some of the air flow, so what, it's part throttle operation. Down stream the throttle valve controls how much air flows into the engine. The throttle valve doesn't care if's it a AFM or a MAF upstream. JMHO (personally I miss carburetors)

Raceboy

[QUOTE=924srr27l;13548781]Yeah, and tell us more about the great British injection systems? Or road cars for that matter lol? Apart from Aston Martin, Rolls-Royce and Range Rover, all of them are a joke.

Gee, get a grip man. Clearly you don't have any idea how to tune any system, you just blabber what others say and you don't even have the capacity to filter what is true and what is BS.
Get over your british arrogance and perhaps you will learn somethign useful in the future.

924srr27l

Yes I agree....but the word restrict is better called "controlled"


Many Race applications are often better (Quicker Laptimes) when a Smaller Inlet and / or Carburettor is fitted, I've experienced this myself on 125cc 6 Speed Shifter karts when the rules changed fro a 40mm to a 32mm Carburettor.


The Karts speed down the straight and the Dyno Power was significantly less ! But the throttle was crisper out the turns especially the slower hairpins... and the overall laptime was quicker. The engines were producing 44 & 35bhp..


With this in mind this is why I didn't go for a bored out throttle body or a large bore exhaust, as my untrained mind was thinking about velocity speeds which are faster with a smaller bore exhaust and as far as the inlet goes a controlled bore and subsequently the amount of air is in the opinion of the tuner what gives these engines the low down torque and for sure his many hours and changes making a new Chip have provided great results.


The Toyota 4A- GE 1600cc (Ford BDA Copy) MR2 16v Engine had a Flap in the inlet system which was closed until approx. 4000rpm this aided low down torque, then when opened the 16v could rev harder and take in more air....


I had a 2002 BMW 2.0 Turbo Diesel that had 4 Flaps in the inlet system to do exactly the same again.


It would seem that any Flap in a system some people think is a Restriction, which if you are / were Racing then maybe it is for constant WOT (Although in the above 3 cases their flaps would be fully open) but the word Restrictive is unfair as they are quite clearly a technical system designed specifically to do a job and they all work really well..


When we start discussing Tuning, and in the case of Porsche's 4 cylinder 2.5/2.7/3.0 Engines this device gets too much stick in my opinion, there are literally thousands of them out there in the world not only still working fine but also still providing people with lots of fun as these engines pull well. Not to mention my application which in combo with some other mods works so well there's no reason whatsoever to change it..


Which should also prompt other members / owners to think twice before going with a small minority who think it's a piece of Junk!





R

924srr27l

Ok, so about a 7% bhp / torque gain
You could get this and more from a live mapping session


I see the original curve is quite spikey, and the other one smoother i'm not sure why this is? could your AFM be worn or something?


This large engine does send pulses back down the inlet which incidentally push and close the AFM flap which is a good thing.


A very common scenario is when people change exhausts and / or take off airboxes and use cones etc..the extra induction & Exhaust noises "Feel" and sound like the car is quicker...! But it's really not.


I've done this in my youth many many times and of course sworn blind at the time it's so much faster...especially on motorbikes.


I would imagine no AFM as well as a cone or not would sound different on the throttle application, I this this plays a big part in comments the throttle is better etc..


The drinking straw thing is a good analogy...but your thoughts are the dead opposite.. , the smaller the faster and easier...the bigger bore the slower and harder...


Hence a flap being controlled by suction will only open as much as the pressure wants, dictated by the throttle butterfly, a variable inlet system in effect great for low and mid range throttle....


Again the classic scenario where someone takes off an air box and sticks on the Afm a massive Cone filter which now has a huge surface area for air to enter...this reduces power.


Look at all the really expensive fully enclosed Air induction Kits for the modern performance cars, the size of the actual inlet is small not large..


Too big is slow and too much volume...Low volume and faster speed is better pick up & response at low RPM and throttle applications..just like the carburettor scenario..


Big Carbs more top end power, smaller more throttle response..


Big is not always best..and often abused with tuning too much...


My Engine now fully mapped is not RICH RICH RICH at all or is there any black smoke..the burn has been perfected from 1000 to 6450rpm


It takes hours of time , expertise and costs but it's well worth it.




R