944 petrol? leaded or unleaded

[silverback mike]

Leaded or unleaded, that is the question....

D reg 944, I can't for the life of me remember what I ran my last one on.

The inside of the filler cap is showing 96 ron...I have a horrible feeling they won't run on unleaded.....Or....is optimax unleaded 96 ron?

Or.....If I put unleaded in, what will happen?

Any ideas...I unfortunately don't have an owners manual to look it up.

TIA Mike.

[interloper]

These engines dont have an issue with unleaded as such but require super unleaded due to the ignition timing.

[silverback mike]

Thank you.

[2alexcoo]

The handbook for my 968 specifies 98 octane fuel, but states it will run on 95 with a loss of power.

Because of this I've always used Optimax, but on the last fillup all I could get was 95 octane Texaco unleaded. To be perfectly honest I can't feel any difference

[AJLintern]

Is that something that specifically applies to the Lux? My S2 runs fine on normal 95ron unleaded

[diver944]

Yes Andy, our S2s are happy on 95RON and were designed for it. They have a knock sensor which will increase advance until the point of knock then retard it a little for safety. 98RON 'should' allow it a tiny performance increase but it really won't be noticeable.

[softinthehead]

the issue of leaded vs unleaded only applies to later models such as the S2 which have a catalytic converter and as such must have unleaded. The earlier models, lux 2.5, 2.7 etc dont have a cat so you can put in whatever you like. This is a separate issue from the RON value of the fuel you put in.
I was told on a previous thread of mine that the 2.5/2.7 doesnt have a knock sensor so it dont matter whether or not you put optimax in or not, it wont make much difference. the S2 however does have said sensor so will benefit from optimax etc. this is regurgitated knowledge so may be b***ocks but its what the combined wisdom of PH led me to understand

[silverback mike]

softinthehead said:

the issue of leaded vs unleaded only applies to later models such as the S2 which have a catalytic converter and as such must have unleaded. The earlier models, lux 2.5, 2.7 etc dont have a cat so you can put in whatever you like. This is a separate issue from the RON value of the fuel you put in. I was told on a previous thread of mine that the 2.5/2.7 doesnt have a knock sensor so it dont matter whether or not you put optimax in or not, it wont make much difference. the S2 however does have said sensor so will benefit from optimax etc. this is regurgitated knowledge so may be b***ocks but its what the combined wisdom of PH led me to understand

Good stuff. I shall throw unleaded in it and see what happens. Thanks to all.

[iguana]

The lead is not really an issue on pork of the last 20 yrs but octane rating is & early 944 should only be run on SL or optimax.

Offical pork info is-

944

82-85= 98oct
86-87= 98oct or 95oct with DME adjusted
88 on (inc 944T, S, S2) 95oct

My 944lux,S2,Turbo have always had 97 or 98 oct optimax in tho when i fueled 'em.

FYI- Super = 97oct, Optimax = 98oct

Leaded is hard to get & only sold at a very very very few small garages nowdays.

[silverback mike]

Thanks Iguana, optimax it is then.

[silverback mike]

iguana.
What's a DME mate?

[matsleight]

This should explain it
www.clarks-garage.com/pdf-manual/fuel-05.pdf
This site used to be good, but looks blank to me at moment - maybe the owwner is updating?
http://frwilk.com/944dme/

[silverback mike]

tks matt

[SianB]

I've been running my 1986 924S on Ultimate with a Redex lead additive, from what I'm reading it sounds as though the additive isn't necessary - am I wasting money or is it worth continuing?
Sian

[silverback mike]

Hi sian.
Well, in theory your engine is exactly the same as mine, it runs perfectly well on unleaded.

[iguana]

silverback mike said:

Hi sian. Well, in theory your engine is exactly the same as mine, it runs perfectly well on unleaded.

No quite true as early 924S is not the exact same engine as 944= lower compression ratio than the 944 & thus 95 octane is fine & dandy.


Sian- yes you dont need lead substitute.

[silverback mike]

iguana said:

silverback mike said: Hi sian. Well, in theory your engine is exactly the same as mine, it runs perfectly well on unleaded. No quite true as early 924S is not the exact same engine as 944= lower compression ratio than the 944 & thus 95 octane is fine & dandy. Sian- yes you dont need lead substitute.

I stand corrected by someone with better knowledge than I.
Nice one Ig......

Ps how do I make my 944 a bit faster...it has a decent filter, sports exhaust....but still feels a bit pedestrian....or do i need a turbo?

[randlemarcus]

Most of the bits about 944 modding I have read seem to indicate that its cheaper, and probably kinder to start with forced induction, rather than supercharge a D reg Lux.
On private roads, my 944 Turbo (250) without any mods, seems to have enough performance to scare the sh1t out of my sister in law

[iguana]

silverback mike said:

Ps how do I make my 944 a bit faster...it has a decent filter, sports exhaust....but still feels a bit pedestrian....or do i need a turbo?

Well as fun as they are, im afraid 2.5Luxs are indeed a bit pedestrian! nowt cheap is gunna have much effect tho, cheapest mod really is to get an S2 or a Turbo.

In the meantime stick the old girl on a rolling road & see whats shes got.

[iguana]

randlemarcus said:

Most of the bits about 944 modding I have read seem to indicate that its cheaper, and probably kinder to start with forced induction, rather than supercharge a D reg Lux.

? bit confused here, as forced induction = not normally aspirated, i.e the air is forced in, thus a turbo or supercharger.