It was only a matter of time....
Discussion
...before I asked:
What type of fuel will make my V8 pop and bang more?
I gather that the higher octane fuels make the car pop and bang more, but are also are better for the car, and would probably be best for me since I have a higher compression ratio in my V8 which Austec say pinks a little (when too hot) untill they clean the injectors.
Does anyone have any reason to believe that any of the fuels below are best at making an engine pop and bang more than the others? Im going to switch over from regular unleaded, but wanted some opinions on which is best for pops and bangs.
Optimax, Esso Super Unleaded, or BP Ultimate.
What type of fuel will make my V8 pop and bang more?
I gather that the higher octane fuels make the car pop and bang more, but are also are better for the car, and would probably be best for me since I have a higher compression ratio in my V8 which Austec say pinks a little (when too hot) untill they clean the injectors.
Does anyone have any reason to believe that any of the fuels below are best at making an engine pop and bang more than the others? Im going to switch over from regular unleaded, but wanted some opinions on which is best for pops and bangs.
Optimax, Esso Super Unleaded, or BP Ultimate.
WildfireS3 said:
Not really any difference that I can see, although my car tends to favour Optimax rather than BP, which I've only used a few times.
Cheers for the mail Chris
Gonna make the switch for sure, extra popping and banging will be nice, cant complain though if one fuel is as good as the other, as super will be better for the car for sure 
If you put diesel in it, it will pop and bang like b
y for a minute or two.
Then it's dead.
Might be worth a try though?
This is a (weak) attempt at humour. Putting diesel in petrol engines is not recommended, except for comic effect or unless you are very very silly indeed. Do NOT try this at home chidren.
>> Edited by tvrgit on Tuesday 31st August 17:52
y for a minute or two. Then it's dead.
Might be worth a try though?
This is a (weak) attempt at humour. Putting diesel in petrol engines is not recommended, except for comic effect or unless you are very very silly indeed. Do NOT try this at home chidren.
>> Edited by tvrgit on Tuesday 31st August 17:52
Rob, did you try the Wynn's Fuel Injector cleaning spray I mentioned the other week?
It's very effective and cost just £6 and some of your time, it made a huge improvement to mine.
You'll need to take the ducting off and spray into the plenum so that it doesn't go thru the filters.
Cheers,
Kevin
It's very effective and cost just £6 and some of your time, it made a huge improvement to mine.
You'll need to take the ducting off and spray into the plenum so that it doesn't go thru the filters.
Cheers,
Kevin
kentishS2 said:
Rob, did you try the Wynn's Fuel Injector cleaning spray I mentioned the other week?
It's very effective and cost just £6 and some of your time, it made a huge improvement to mine.
You'll need to take the ducting off and spray into the plenum so that it doesn't go thru the filters.
Cheers,
Kevin
I considered it, but... dont have any tools, and Paul (austec) said my injectors were in such bad shape, 2 of them might need replacing. So I decided for best results I really ought to get them to do the job properly when they get the car MOT'd next month. Not everyone would do what Im doing, but once sorted properly, that'll be the end of the problems - besides, Paul recons the problem is holding back quite a few more bph so Im curious and will opt for another hour on the RR when its been done.
A little more costly then £6, but I keep telling myself once its been done, that'll be it
Cheers anyway mate.
kentishS2 said:
Rob, did you try the Wynn's Fuel Injector cleaning spray I mentioned the other week?
It's very effective and cost just £6 and some of your time, it made a huge improvement to mine.
You'll need to take the ducting off and spray into the plenum so that it doesn't go thru the filters.
Cheers,
Kevin
A bit
me on tis one, I thought the injectors had to be cleaned onteh inside ie with afuel addative or on a test bench/stripped down. How does spraying into the AIR intake clean the injectors
. Harry
Rob, Harry,
I tried the additives and they were rather "placebo" on mine!
I was about to remove them and send them off to Lucas CAV for refurb when I spotted the Wynns and thought for £6 I'd give it a go. I did and it worked but I do agree that it can only work on the nozzles and not within the injectors bodies, I can only guess that the majority of the crap is situated at the nozzle?
Perhaps the additive also worked but I just needed something stronger on the injector nozzles??
>> Edited by kentishS2 on Tuesday 7th September 14:54
I tried the additives and they were rather "placebo" on mine!
I was about to remove them and send them off to Lucas CAV for refurb when I spotted the Wynns and thought for £6 I'd give it a go. I did and it worked but I do agree that it can only work on the nozzles and not within the injectors bodies, I can only guess that the majority of the crap is situated at the nozzle?
Perhaps the additive also worked but I just needed something stronger on the injector nozzles??
>> Edited by kentishS2 on Tuesday 7th September 14:54
Pies said:
This site is worth a read
www.asnu.com
Ummmmmmm almost convinced me mine must need doing then, been playing up lately, over rich mixture, not showing faults, down to low teens on a normal drive

. How much to clean the injectors then
. Did you remove them yourself Pies and if so how
, how much of reduction to turn up with set in your hands to be flow tested and cleaned
. Harry
Harry,
I have a contact at Lucas (I used to work for them) and they quoted me approx £25 each if I take them in to be done. This is using the ASNU system.
I may still have them done but they seem OK at the moment, I'll judge what they are like when I've replaced the fuel pressure reg and the ignition leads.
I have a contact at Lucas (I used to work for them) and they quoted me approx £25 each if I take them in to be done. This is using the ASNU system.
I may still have them done but they seem OK at the moment, I'll judge what they are like when I've replaced the fuel pressure reg and the ignition leads.
Its quite a bit of work on the V8 Harry and TBH I wouldnt do it again
You have to strip of down to and including the trumpets
You can then lift up the fuel rail and pull the injectors out
Make sure you get all the "O" rings out as sometimes they stick in the rail
Replacing is even worse as its very easy to pinch an "O" ring,but use a bit of vaseline for lubrication not silicone {small]down Podie
Phone Austec and ask Mike or Paul how much,but as i said id rather not DIY again
You have to strip of down to and including the trumpets
You can then lift up the fuel rail and pull the injectors out
Make sure you get all the "O" rings out as sometimes they stick in the rail
Replacing is even worse as its very easy to pinch an "O" ring,but use a bit of vaseline for lubrication not silicone {small]down Podie
Phone Austec and ask Mike or Paul how much,but as i said id rather not DIY again
The higher the octane the slower the flame front will be, so if the timing remains static then it is more likely un-burnt fuel will enter the exhaust where it can ignite and make a loud pop.
You can get a bang on the overrun during change up by getting the rpm spot-on. There will be a sweet spot where the inlet charge will have the greatest fuel saturation (as you lift off at full throttle there will be an instant when the inlet gas volume is reduced, but the injectors are still firing before the hotwire sensor can heat up. ) If unburnt charge comes out into the exhaust you can get a fantastic bang. My V8S achieves this on most occasions if you change over 4500 rpm
Running high duration cams with loads of overlap gives you similar effects due to unburnt inlet charge exiting the cylinders before the exhaust valves close, but I can only dream about that.
Z
You can get a bang on the overrun during change up by getting the rpm spot-on. There will be a sweet spot where the inlet charge will have the greatest fuel saturation (as you lift off at full throttle there will be an instant when the inlet gas volume is reduced, but the injectors are still firing before the hotwire sensor can heat up. ) If unburnt charge comes out into the exhaust you can get a fantastic bang. My V8S achieves this on most occasions if you change over 4500 rpm
Running high duration cams with loads of overlap gives you similar effects due to unburnt inlet charge exiting the cylinders before the exhaust valves close, but I can only dream about that.
Z
Pies said:
Just checked I paid £21 each at Austec,this involved me removing them
I was quoted £18 each plus 2 hours labour, so £250 (By Austec) plus the remap costs so more like £400 inc vat. Mike said "We are only 70% there with the car, and have done the best we can on the RR with the injectors as they are"
Im just hoping my 254bhp figure will go through the roof... but Im not holding my breath. Paul said he was sure he could find another 8, we will have to see. I just want to get the car running on top form, then im calling it quits (for another 15 years, till Ive recovered)
ukbob said:
Pies said:
Just checked I paid £21 each at Austec,this involved me removing them
I was quoted £18 each plus 2 hours labour, so £250 (By Austec) plus the remap costs so more like £400 inc vat. Mike said "We are only 70% there with the car, and have done the best we can on the RR with the injectors as they are"
Im just hoping my 254bhp figure will go through the roof... but Im not holding my breath. Paul said he was sure he could find another 8, we will have to see. I just want to get the car running on top form, then im calling it quits (for another 15 years, till Ive recovered)
my price included VAT,before anybody gets

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