Rogeyboy

iTrader: (2)

What about on over-run after nailing it for a prolonged time... I worry that my engine will get mega hot as the fuel cuts on over-run, esp after ive had my foot in for a while.

It is definately fun and daunting mapping my car myself

Chip

iTrader: (3)

If you have a fuel CUT on overrun, ie no fuel injected at all, what do you think is going to make it get hot?

Karlos G

iTrader: (4)

Yeah as above, the engine will just be pumping cold air through it on overun if you fuel cut.... Helps to cool it down mate!

Rogeyboy

iTrader: (2)

I dunno just worries me as the afr gauge goes mega lean... I hadnt thought of it like that. Im stuck in the thought of more fuel = cooler engine. I guess not so lol

Now i feel abit dumb lol

Karlos G

iTrader: (4)

lol! More fuel means a cooler burn yes.... But when your burning nothing and just pumping fresh air through can't get much cooler!

Rob_DOHC

iTrader: (4)

More fuel does mean a cooler combustion chamber. On larger powered cars with very high exhaust temps people deliberate don't cut fuel on the over run... You will be fine though.

To make something hotter you need to add more energy to the system, injecting no fuel means no combustion so no more energy is added, so no more heat is generated sweeeet.

Combine this with the fact that your engine isn't under load when on the over run, and is in fact just an air pump and things begin to look massively safe

Racelogic make traction control units, these limit power by cutting a full injector pulse from alternate injectors every cycle, people use these with 800 bhp supras and live to tell the tail.

The mega manual warns against using deacel fuel enrichment (different to fuel cut) on a turbo charged car, as you can still be making boost after slightly closing the throttle which could trip deacel fuel briefly... and force a lean spike at high boost... I have never had this happen and usually inject 90% of fuel on the over run before fuel cut.

The worst thing about fuel cut on the over run I found was a slight stumble when applying throttle in this state. But I think my new setup will cope with this better.

Rob,

Chip

iTrader: (3)

Decel enleanment you mean

Rogeyboy

iTrader: (2)

Yeah i get a slight stutter when re applying throttle, altho nothing noticable from a passengers pov... Something i'll look into
My decel cut, comes in after 2 secs and the afrs go nice and rich for the 2 sec window before the cut...

Rob_DOHC

iTrader: (4)

Yes lol, i stuck with enrichment as its under the same menu, and for the life of me cant remember what TS calls it.

Rob_DOHC

iTrader: (4)

AFR's going very rich when you lift off is something EAE will sort out, its all the fuel thats stuck on the inlet being sucked off when the throttle butter fly is closed, decel enleanment (thank you sir chip) will help a little, although i've never found it got rid of the rich segment just after closing the throttle... If you AFR's stay very rich for a long period after closing the throttle decel enleanment will help, if it just goes rich for a short period them EAE will be the correct fix.... However its far less annoying than a lean spike upon throttle opening

In an ideal world, your AFR's wouldn't change at all when opening closing the throttle, not even OEM's get this bit totally spot on, in fact my 328 goes pretty rich when the throttle is opened, i suspect to encourage a smooth transition from closed to open.

Rob,

Rogeyboy

iTrader: (2)

Have you fitted an AFR gauge to your 328i...? Cheeky
I'll start to have a look at EAE at some point maybe, im getting the hang of the rest for now lol.

Rob_DOHC

iTrader: (4)

I need to give you a txt in a min mate! I fitted the one from my escort temporarily because i wanted to see what kind of afr's oem cars run etc. Plus im thinking of making an ecu for the 328 as i fancy a small rotrex supercharger when one comes up at a good price on ebay

Rob,

Chip

iTrader: (3)

you'll be waiting a long time for that I suspect, rotrex always seem to fetch good money on ebay.
I'd like to get my hands on a couple on the cheap myself TBH!

Rob_DOHC

iTrader: (4)

I know! Or a vortech, tbh I would prefer an eaton/screw type but there really isn't much space

Chip

iTrader: (3)

The eaton screw types arent great for standard CR generally either.

Im trying to find room on my nova for one at the moment and struggling!

Rob_DOHC

iTrader: (4)

Haha, good man... compound using the turbo too or with a switch over valve? I generally just prefer the power delivery of an eaton to the the compressor type chargers even if it means running less boost to avoid det at lower rpm high load areas... but the rotrex blowers are so easy to find room for!

Theres a firm that make a new inlet for the bmw 6pot, with an eaton bolted to the side for good measure, its a steal at £4000



Nice castings though! But I can get the mounting brackets laser cut easily for the rotrex type



Think I can do the whole conversion for around £1000.... maybe lol

Sorry for going off topic Roger!

Rob,

Chip

iTrader: (3)

I'm going to compound charge with it, probably the turbo blowing into the supercharger, although I might go for the charger blowing into the turbo then have a switchover at a particular boost point, not really decided yet as need to get the damn thing mounted first and thats not proving trivial at all!

Might just end up sticking with only the turbo and spool it with nitrous instead!

Rogeyboy

iTrader: (2)

No worries guys... As long as its MS managed its kinda on topic lol.

Chip - How come the switch from ford to vauxhall?

Chip

iTrader: (3)

No switch mate, still got the ford, and had vauxhalls before I bought it.

You'll be pleased to here my XE corsa is on MS though although the nova I just mentioned isnt, its on a hacked about (ie free) version of the saab management.

TBH if I have switched to anything recently its more to the clios, we've got 3.5 of them at the moment.


I'm just a petrol head in general, not got any one particular make that I am into, just anything that is a good car irrelevant of the badge.

Rob_DOHC

iTrader: (4)

Dont think he switched dude, he still has a 3door as far as i know.... And im not sure how much vauxhall is left in the nova

Rob_DOHC

iTrader: (4)

Right from the horses mouth lol

Rogeyboy

iTrader: (2)

Oh ok, my bad lol.
Still got the ex cover car 3door, thats in your avatar?