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ppj_racing

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What normal & max boosts are y'all using ?

And what fuel ??

Cheers

J of PPJ


Turbo Shed

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i use super unleaded and run 10psi normal and up to 20psi

i dont see the relavence of fuel against boost though.


ppj_racing

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On 16th of May, 2007 at 12:31pm Turbo Shed said:
i use super unleaded and run 10psi normal and up to 20psi

i dont see the relavence of fuel against boost though.


Higher RON helps prevent det !

When you say 10 psi do you mean 10 psi gauge?
i.e. 0.66 bar ?

see also

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=152826

Edited by ppj_racing on 16th May, 2007.


Turbo Shed

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higher Ron may help reduce det but so does a low compression ratio or a good intercooler or if its well set up etc etc etc.

high Ron fuel in a standard metro turbo engine will allow a bit more boost (depending on how high the Ron is) but a decent engine with all the bells and wistles can run higher boost on standard pump fuel

and yes 10 to 20 Psi is gauge pressure, if i'm right then if that was actual pressure then 10psi would be -5psi gauge so is a vacum


ppj_racing

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On 16th of May, 2007 at 12:50pm Turbo Shed said:
higher Ron may help reduce det but so does a low compression ratio


What's your Base CR then ?


ppj_racing

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On 16th of May, 2007 at 12:50pm Turbo Shed said:
higher Ron may help reduce det but so does a low compression ratio or a good intercooler or if its well set up etc etc etc.

high Ron fuel in a standard metro turbo engine will allow a bit more boost (depending on how high the Ron is) but a decent engine with all the bells and wistles can run higher boost on standard pump fuel

and yes 10 to 20 Psi is gauge pressure, if i'm right then if that was actual pressure then 10psi would be -5psi gauge so is a vacum



Yup, off-boost your gauge should show a negative figure
Most n-a engines have a volumetric efficiency well below
100 ..so when your boost gauge shows O psi, you have
100 VE and can get-on with some serious boosting

Provided the other hardware can stand-it, espesh temp
as you say, if you use a RON of 120 ,, or some
Avgas (even 100LL) or better, xylene or even better
methanol (runs cooler + much more power), you
can run a base CR of say 7.8 i.e. 15.6 at 1 bar boost
and get better results.

That said, a lower Base CR does give you less lag
and less power

How much are you getting at the wheels?


evolotion

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On 16th of May, 2007 at 01:14pm ppj_racing said:

your boost gauge shows O psi, you have
100 VE and can get-on with some serious boosting


??? any horribly inefficient engine can achieve 0psi(gauge) in the inlet, it is completely irrelevent to the VE of the engine or am i missing your point?

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.


Turbo Shed

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my C/R is 8:1 and i have tried 116ron fuel and it makes it run nice but make no real difference on the strip but then i only ajusted the mixture a bit.

its not been on the rollers for some time, last time it was 130bannanas and befor that it had 150 but felt the same (different places) and at thats at the flywheel


turbodave16v
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On 16th of May, 2007 at 01:29pm evolotion said:



On 16th of May, 2007 at 01:14pm ppj_racing said:

your boost gauge shows O psi, you have
100 VE and can get-on with some serious boosting


??? any horribly inefficient engine can achieve 0psi(gauge) in the inlet, it is completely irrelevent to the VE of the engine or am i missing your point?




I don't get this either...*oh well*

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JT

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On 16th of May, 2007 at 01:14pm ppj_racing said:


That said, a lower Base CR does give you less lag
and less power




i always thought lower CR gave you MORE lag and less power?

My build thread..

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=542985


Ric

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Basingstoke

yeah, i thought that too. Higher cr mean's it will behave like a 'normal' engine off boost. Low cr engines are usually crap off boost (which i assume will make it more laggy) then take of like a rocket when the turbo spools.

A lot of guys on here seem to have found a sweet spot without much lag and allowed them to run big power. If lag is going to bother you, get a t2, some guys have had great results with them.


JT

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im planing on using a t2 (eventualy a hybrid one) with a cr of 8.29:1.
shouldnt be too bad off boost i wouldnt of thought especialy as it should be on boost quickly (hopfully!)

My build thread..

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=542985


stevieturbo

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Lots of odd info here....


Bottom line is, you want to use the minium amount of boost, the cheapest fuel and the highest CR, to make the most power you can.

Easy *happy*

Well, if only it was !!

Max boost used etc etc is meaningless. Fuel and ign control are vital, intercooling of course is also..

As for fuel ? Wasnt it mentioned here recently that Avgas is actually pretty crap as a performance fuel ?
Either way, I dont see regular SUL fuel as much of a limitation to making decent power.
You will run into clutch/gearbox problems long before fuel becomes a limiting factor.

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202mph standing mile
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joeybaby83

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the way i look at boost is that its a neccesary evil to get more power, the less you have to use, the better

if you and a mate both had 150 or so nana's, and you were running 20 psi and he only needs 10 for instance, wouldnt you feel a bit silly?

a poor example i know, but do you catch my drift?

"Turbo's make torque, and torque makes fun"

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evolotion

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my car was tuned simply by getting the CR as low as i could, and then running as much boost as i could on supermarket 95 ron fuel, that way my car can produce 100% of its potential power 100% of the time. i view special fiels like i view nitrous, cheating *happy* as last time i checked my local BP had neither methanol or N2O at the pump :)

Edited by evolotion on 16th May, 2007.

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.


Bat

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Hi,
Noz at the BP, LOL!
Mind you it'd be alot cheaper at Morrisons *wink*
Cheers,
Gavin :)

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ppj_racing

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On 16th of May, 2007 at 01:29pm evolotion said:


??? any horribly inefficient engine can achieve 0psi(gauge) in the inlet, it is completely irrelevent to the VE of the engine or am i missing your point?



I quote

" a VE over 95% is excellent, and 100% is achievable, but quite difficult. Only the best of the best can exceed 110%, and that is by means of extremely specialized development of the complex system comprised of the intake passages, combustion chambers, exhaust passages and valve system components.

Generally, the RPM at peak VE coincides with the RPM at the torque peak. And generally, automotive engines rarely exceed 90% VE. "

so, if your Racing Team's inefficient engines are easily achieving 100% VE, can we have one please? It'd be a much better starting point than our 95-98% one


evolotion

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On 16th of May, 2007 at 01:14pm ppj_racing said:
so when your boost gauge shows O psi, you have
100 VE


you said 0 psi(gauge) in the inlet = 100% ve.

i know 100% ve in nat-asp form is a very admirable target, that wasnt what i was querying.


turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.


ppj_racing

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On 16th of May, 2007 at 06:10pm stevieturbo said:
Wasnt it mentioned here recently that Avgas is actually pretty crap as a performance fuel ?



Lots of turbo guys with SERIOUS motors still use Avgas
even the 100LL enhance with a tad of xylene, isoprene
and/or meths. Anything that gives you a RON of over 107
is OK.


ppj_racing

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On 16th of May, 2007 at 08:16pm evolotion said:
my car was tuned simply by getting the CR as low as i could, and then running as much boost as i could on supermarket 95 ron fuel, that way my car can produce 100% of its potential power 100% of the time. i view special fiels like i view nitrous, cheating *happy* as last time i checked my local BP had neither methanol or N2O at the pump :)


Do yourself (and your engine) a favour and use Shell Optimax at least


ppj_racing

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On 16th of May, 2007 at 01:31pm Turbo Shed said:
my C/R is 8:1 and i have tried 116ron fuel and it makes it run nice but make no real difference on the strip but then i only ajusted the mixture a bit.

its not been on the rollers for some time, last time it was 130bannanas and befor that it had 150 but felt the same (different places) and at thats at the flywheel


You'd notice that nice RON 116 would prevent det if you boosted higher

Some said "Max boost is meaningless" .. can't remember
what planet they were from, though*tongue*

As for your 130 bhp, what capacity engine and what boost?
Nice base CR though.


ppj_racing

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On 16th of May, 2007 at 06:10pm stevieturbo said:
Lots of odd info here....


Bottom line is, you want to use the minium amount of boost, the cheapest fuel and the highest CR, to make the most power you can.




Seems completely back-to-front to me, especially using
cheapo fuel. If you're not going to boost much
use a supercharger instead, and leave turboing to
the real racers


evolotion

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On 19th of May, 2007 at 04:26pm ppj_racing said:



On 16th of May, 2007 at 08:16pm evolotion said:
my car was tuned simply by getting the CR as low as i could, and then running as much boost as i could on supermarket 95 ron fuel, that way my car can produce 100% of its potential power 100% of the time. i view special fiels like i view nitrous, cheating *happy* as last time i checked my local BP had neither methanol or N2O at the pump :)


Do yourself (and your engine) a favour and use Shell Optimax at least


appreciate the concern but no, the car is a daily drive (well currentl off the road for some minor rot sorting) i have built engiens in the past that relied on 97+ octane, and found myself caught out on a few occations. However when i know im going to be giving it lots of large i will run super unleaded purely for the extra safety :)

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.


turbodave16v
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PPJ - no one else has said it, so I will.

It is not a great idea to come on a forum, telling folks how you have a great big plan, whilst admitting you have never turbocharged before, and start calling the odds or telling folks they're doing it wrong.


Hope that is clear enough for you.

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stevieturbo

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On 19th of May, 2007 at 04:34pm ppj_racing said:


Seems completely back-to-front to me, especially using
cheapo fuel. If you're not going to boost much
use a supercharger instead, and leave turboing to
the real racers


From reading through this thread...I understand why you dont agree *wink*

Cheapo fuel ??? 99% of people here drive road cars. Filling up with exotic fuels would be rather expensive for a road car.
Besides, ive never had a problem making power on regular SUL fuel.
You could easily make enough power on SUL to blow an A-series apart..


Boost boost boost...it isnt all about boost. Its about making power....using higher compression and lower boost, will generally be more efficient. So why go lower CR than you need to in order to achieve your goals ?
Fuel economy, low end response etc will all suffer with lower CR's, which for a road car, are all important things.

Perhaps for a race car they may not matter as much...but so many here arent race cars. They may race them on occasion though. But its not the same thing.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

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