stevebh 0 Report post Posted October 12, 2006 Hey guys just bough a 1995 320i and just wondering what type of petrol you would reccommend? Either 91 or 95? Quote Share this post Link to post Share on other sites
stevebh 0 Report post Posted October 12, 2006 The owners manual recommends 95 or better but says you can run it on 91 but yoou are likely to have increased fuel consumption Cheers, talking about owners manuals you wouldnt know where to buy/download one, mine is entirely in Japaneese Quote Share this post Link to post Share on other sites
jpp 0 Report post Posted October 12, 2006 Mobil/Caltex are better than FlyBuy points... Quote Share this post Link to post Share on other sites
kerrynzl 3 Report post Posted October 12, 2006 Cheers, talking about owners manuals you wouldnt know where to buy/download one, mine is entirely in Japaneese In the Wanted to Buy Column under "Bentley Manual' I left a site for a E36 Bentley to download one last thing, Too high an Octane will Fowl Plugs slowly but: Too Low an Octane causes Detonation When in doubt, choose the Higher Number, it's safer Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted October 12, 2006 (edited) I have an E30 owners manual here if interested - whoops sorry misread Cheers Grant Edited October 12, 2006 by hotwire Quote Share this post Link to post Share on other sites
Yuen 16 Report post Posted October 12, 2006 Go for 95 at the very least. If you put 91 in you will notice less power, I did! Quote Share this post Link to post Share on other sites
TronSpec 0 Report post Posted October 12, 2006 Yeah man if you can afford it go with the higher octane. Better for the engine and hey you can allways replace plugs and sh*t. Quote Share this post Link to post Share on other sites
Carl 3 Report post Posted October 12, 2006 I run both for the hell of it and can't tell the f**king difference except for the cost of a full tank. If you can show me on a dyno that 91 performs worse then i'd agree but since 91 doesn't pink in my car then it's good to run. Quote Share this post Link to post Share on other sites
Docile 64 Report post Posted October 12, 2006 well first time i got the car i was running it on 91 for about 2 weeks... ive got an e36 btw then i tried the 95... and damn you can really feel the difference.. the engine responses better.. tried the BP 98 too, even better response but hecka more expensive Quote Share this post Link to post Share on other sites
MADBMA 0 Report post Posted October 12, 2006 (edited) since petrols dropped down a notch i been using 98 where ever i can find it but 95 or higher, i would never put 91 in her, what you put in is what you get out Edit: 94 E36 btw Edited October 12, 2006 by MADBMA Quote Share this post Link to post Share on other sites
jpp 0 Report post Posted October 12, 2006 Someone above said that a higher number also results in less fuel consumption? [taken out of context i know] Could someone please elaborate on this... how much ratio difference are we talking? [as i'm on a tight budget heh] Quote Share this post Link to post Share on other sites
Guest Andrew Report post Posted October 13, 2006 I run both for the hell of it and can't tell the f**king difference except for the cost of a full tank. If you can show me on a dyno that 91 performs worse then i'd agree but since 91 doesn't pink in my car then it's good to run. Every m20 i've chucked 91 into pinks like a mofo under any kind of load. Quote Share this post Link to post Share on other sites
Carl 3 Report post Posted October 13, 2006 Every m20 i've chucked 91 into pinks like a mofo under any kind of load.I've seen some do that, but not mine, my little nippon import runs happily on 91Tend to use 95 during the cold winter months though, the 95 seems to do extremely cold starts better Quote Share this post Link to post Share on other sites
bravo 35 Report post Posted October 13, 2006 Someone above said that a higher number also results in less fuel consumption? [taken out of context i know] Could someone please elaborate on this... how much ratio difference are we talking? [as i'm on a tight budget heh] i don't know the reason why it works, but if I work out the kms I get from a tank of 98 and the kms I get from a tank of 95 and divide by the cost I get the same $ per km as the 98 goes futher. on that basis you could run whatever you prefer as the cost per km is about the same even though the cost per litre is not. Quote Share this post Link to post Share on other sites
kerrynzl 3 Report post Posted October 13, 2006 Someone above said that a higher number also results in less fuel consumption? [taken out of context i know] Could someone please elaborate on this... how much ratio difference are we talking? [as i'm on a tight budget heh] Heres a basic explaination The Higher the octane the slower the burn time [Flame propagation], the higher the compression the faster the burn time [plus more heat] the more heat=more cylinder pressure [more torque] with high octane fuels you can have higher compression [M50B20's have 11:1 which is 'racing' compression ratio's of 20years ago] with high compression & high octane the Engine can take more ignition advance[which yields better flame propagation,& a complete burn when the piston is exactly at TDC][the point of maximum cylinder pressure] when you run low octane in the same engine it will usually detonate [pinking] under load, what the driver usually does is 'back off the throttle' this effectively lowers Cylinder pressure by restricting intake [a vacuum guage will show that] Incidentally the engine doesn't care about compression ratios [it's cylinder pressure that counts] ,a long duration Camshaft will lower cylinder pressure [cams & compression go together] BMW used a short duration cam for torque, then altered the advance for RPM's [VANOS] If your engine has a knock-sensor, you can run any fuel ,as the engine advances it self up to [just shy of] detonation,which is maximum cylinder pressure [approx 1800psi] An engine makes maximum power at detonation [it doesn't last long tho'] Quote Share this post Link to post Share on other sites
cainchapman 0 Report post Posted October 13, 2006 And in conjunction to Kerry's description. More torque, means that you can use less throttle position for the same motive power. The best of both worlds. You can have a little more economy (however, the fuel costs more, so not a monetary saving) and more kW, when you need them. Quote Share this post Link to post Share on other sites
Mikal 4 Report post Posted October 13, 2006 What should I be putting in my gutless e30 318i? I thaught a higher octane might blow my car up Quote Share this post Link to post Share on other sites
kerrynzl 3 Report post Posted October 13, 2006 What should I be putting in my gutless e30 318i? I thaught a higher octane might blow my car up The dead opposite mate! As I stated earlier TOO high an octane will only foul the plugs too low octane [for it's compression] is more 'likely to blow it up' My Race-car has 13:1 compression [which makes good power] It NEEDS high octane to survive! [avgas 100-112 octane] The reason the public was sold on low octane, was when lead was removed from fuels [we didn't have the technology to produce high octane unleaded 'cheaply'] Lead ruins a catylitic converter What should I be putting in my gutless e30 318i? I thaught a higher octane might blow my car up The dead opposite mate! As I stated earlier TOO high an octane will only foul the plugs too low octane [for it's compression] is more 'likely to blow it up' My Race-car has 13:1 compression [which makes good power] It NEEDS high octane to survive! [avgas 100-112 octane] The reason the public was sold on low octane, was when lead was removed from fuels [we didn't have the technology to produce high octane unleaded 'cheaply'] Lead ruins a catylitic converter Thanks for that Cain Quote Share this post Link to post Share on other sites
Mikal 4 Report post Posted October 14, 2006 (edited) kerrynzl Posted Yesterday, 09:26 PM The dead opposite mate! As I stated earlier TOO high an octane will only foul the plugs too low octane [for it's compression]is more 'likely to blow it up' I learn something new everyday on this site Edited October 14, 2006 by Mikal Quote Share this post Link to post Share on other sites
Mikal 4 Report post Posted October 17, 2006 Well i put $30 of 95 in today and drove to school and back (72km trip there and back) and I didn't notice a change. Quote Share this post Link to post Share on other sites
petone 0 Report post Posted October 17, 2006 Try it with a full tank of 95. I can tell the difference between 91 and 95, not so much with 98 and 95, might just be more placebo effect. It just generally runs smoother and better economy, and the extra 5c a litre is stuff all really when paying 1.45 a litre. Quote Share this post Link to post Share on other sites
cainchapman 0 Report post Posted October 17, 2006 I'd be surprised if you can tell the difference using your arse dyno. A 318 might give you an extra 2.5kW going from 95 to 98 and a little more from 91 to 95. Get it onto a dyno for empirical proof. Quote Share this post Link to post Share on other sites
Mikal 4 Report post Posted October 17, 2006 Full tank? dyno? well im broke, I had to sell a sub an work for dad stacking wood to pay for this weeks petrol, W.O.F an rego. So if there is anyone in Whangarei who needs a part time worker please give me a job do it for my Bimmer. Quote Share this post Link to post Share on other sites
