Octane booster
Author
Discussion

piooly

Original Poster:

1,176 posts

255 months

Thursday 11th August 2005
quotequote all
Hey guys.

Ok confession time. The other sunday, I went out with Gooby and the group to a hill climb. Most of the owners have the 111R. Now a few of you felt that my sport 160 was very quick indeed. Now for the truth. I always use optimax, but for this day I added a bottle of octane booster to the tank. Basically I was running racing fuel at 102ron. Thats what they use on track. Had to make the day a little interesting didnt I !

As you know I sell induction kits etc... I am about to place an order for some boxes of Millers CVL Turbo. This will boost Optimax to 102ron. and believe me, mine flys with this is, feels like NOS !!!! If your intrested in buying some, a 500ml bottle will cost you £7, £10 in the shops. Let me know soon !

kill_zippy

53 posts

259 months

Thursday 11th August 2005
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Ah, but dont you need a cat for that?

Davey S1

13,394 posts

284 months

Thursday 11th August 2005
quotequote all
I was under the impression that the K Series engine didnt have a knock sensor and as a result thge ecu is unable to tell the difference in RON.

gooby

9,269 posts

264 months

Thursday 11th August 2005
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Cheater!

....phew, I thought my car was slow

cuzza

2,042 posts

283 months

Thursday 11th August 2005
quotequote all
Davey S1 said:
I was under the impression that the K Series engine didnt have a knock sensor and as a result thge ecu is unable to tell the difference in RON.


bogie

17,100 posts

302 months

Thursday 11th August 2005
quotequote all
yep - its purely a placebo running more than 95RON in a K engined Elise...unless youhave an aftermarket ECu mapped for 98 RON or higher etc.

piooly

Original Poster:

1,176 posts

255 months

Thursday 11th August 2005
quotequote all
Well, I have to disagree. My car went like a missile on that stuff. I have normal unleaded in at the moment and just doesnt pull anywhere near as well. Cant wait to fill up with the good stuff again.

As gooby experienced, definetely improved my car. Try it, what you got to lose?? I wish I could put in in everyy tank. So 111R boys, you going to be trying it then???

Oh and you can run with it with a CAT or without, doesnt matter.

enjoy...

randy

544 posts

306 months

Thursday 11th August 2005
quotequote all
Complete tripe. Won't make bugger all difference and FYI people don't often race with octane booster. Either normal fuel, optimax or proper race fuel like 76 110. Performance gains will only be made if the engine is mapped on the particular fuel you are using.

andrewm

305 posts

266 months

Thursday 11th August 2005
quotequote all
Have to agree with Randy - Octane booster will help stop detonation if you are running a high compression ratio, but makes very little difference to a road engine.

You can get 120 octane from Sunoco but unless the car is set up for it, it would do more harm than good.

I think Piooly's 160 is just a quick car - that Sunday was quite cool and damp which will give the car more power rather than the warm dry weather we have at the moment.


>> Edited by andrewm on Thursday 11th August 13:30

Davey S1

13,394 posts

284 months

Thursday 11th August 2005
quotequote all
Optimax does make a difference in my Exige but then its not a K series engine.

In a K series Optimax is only worth it for the cleaning properties.

bogie

17,100 posts

302 months

Thursday 11th August 2005
quotequote all
Davey S1 said:
Optimax does make a difference in my Exige but then its not a K series engine.

In a K series Optimax is only worth it for the cleaning properties.


DING!

SpeedyDave

417 posts

256 months

Thursday 11th August 2005
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Piooly, I think you're imagining it (see comments about placebo above). Your compression ratio is fixed, you aren't on boost, and without a knock sensor the K is tuned by necessity for its lowest common denominator fuel - 95 octane. It simply can't tell its got higher octane fuel so the only option it would have had (more aggressive ignition etc) is closed to it.

People seem to always seem to confuse the idea of octane rating with calorific value, thinking it creates a bigger push on the piston. It doesn't work like that. High octane means higher detonation resistance which in turn allows you to run greater compression/boost/ignition advance and so make more power. Higher octane may even mean lower calorific ie marginally lowering power unless you take advantage with boost etc.

Consider this, Tetraethyl lead is a pretty good (and now banned / obsolete) knock resistance agent. Its not a fuel and doesn't 'burn' as such, but when added to fuel it can increase the octane rating. Do you expect to automatically get more power from adding something that doesn't burn?

Dave

jrchannon

153 posts

281 months

Thursday 11th August 2005
quotequote all
i posted on this on the other thread - "Placebo" is probably the correct word here.

This is far from the first time this point has debated. Any mechanic who knows the K series unit will tell you exactly the same.

GreenV8S

31,027 posts

314 months

Thursday 11th August 2005
quotequote all
As far as I understand it, changing the octane rating of the fuel makes no difference to the calorific value of the fuel i.e. the amount of energy it releases when you burn it. But fuel with a higher octane rating is more resistant to pinking which means you can advance the ignition further, this can potentially deliver more power. But unless you actually do advance the ignition, I wouldn't expect to see a measurable change in power output.

SpeedyDave

417 posts

256 months

Thursday 11th August 2005
quotequote all
Yup I agree (note the words "may" and "marginal" above. I was just trying to reinforce the point that Increased Octane <> Increased Calorific value by illustrating how higher octane could infact result in lower C.V. (ie substituting combustable fuel with non combustable antiknock materials)
A higher octane fuel might bring with it a higher C.V. (or a lower one, or unchanged) just depends on the formulation.

Main point is, Octane and C.V. are different things and improving the octane does you no good if you don't take steps to take advantage of it.

GreenV8S

31,027 posts

314 months

Thursday 11th August 2005
quotequote all
SpeedyDave said:
The whole answer.

For some reason your post didn't appear until well after I posted my explanation, I think you covered it rather better though.

scuffham

20,887 posts

304 months

Thursday 11th August 2005
quotequote all
SpeedyDave said:
Yup I agree (note the words "may" and "marginal" above. I was just trying to reinforce the point that Increased Octane <> Increased Calorific value by illustrating how higher octane could infact result in lower C.V. (ie substituting combustable fuel with non combustable antiknock materials)
A higher octane fuel might bring with it a higher C.V. (or a lower one, or unchanged) just depends on the formulation.

Main point is, Octane and C.V. are different things and improving the octane does you no good if you don't take steps to take advantage of it.


well put.

racing fuel's usually leave out all the detergents etc becuse of this, the more you add, the less the CV of the fuel.

S Works

10,166 posts

280 months

Thursday 11th August 2005
quotequote all
Some good tech fact - I like it

The good news from my perspective is clearly that Sport 160S's are as fast as 111R's. I've saved a fortune in that case AND I don't have a pea-shooter for an exhaust

SpeedyDave

417 posts

256 months

Thursday 11th August 2005
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Well thats not far from the truth. An S160 actually has a very similar power to weight ratio to the somewhat heavier 111R and lightness is your friend in the corners.

111R will do you for top speed and acceleration at higher speeds tho.

piooly

Original Poster:

1,176 posts

255 months

Friday 12th August 2005
quotequote all
Well I matched a 111R up to 130 then we both had to brake, on track of-course. S160 actual has 2 bhp per ton more than the 111R ! cant be bad. and thats a standard 160, mine should be producing some more ponnies.......