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Tom Fenton
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Fearless Tom Fenton, Avon Park 2007 & 2008 class D winner

&

TM legend.

Rotherham South Yorkshire

Did some calculations last night of the CR of the engine I am building.

It comes out at 7.5:1 which I am quite happy with.

But I just was wondering what the rest of you guys out there use?

So post up your CR's please!


On 29th Nov, 2016 madmk1 said:


On 28th Nov, 2016 Rob Gavin said:
I refuse to pay for anything else


Like fuel 😂😂


minimark

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2641 Posts
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Post Whore

newcastle

8/1

Everyone knows that instructions only have to be read if the thing doesn't work....


AlexF2003

5795 Posts
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AFRacing LTD

Newbury, Berks

somewhere between 8 and 8.5:1


www.afracing.com/cr.xls


Feel free to have a play!

Alex

AlexF


Turbo Phil

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4641 Posts
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My sister is so fit I won't show anyone her picture

Lake District

7.8-1.

Phil. *smiley*

WWW.TURBO-MINI.COM


Tom Fenton
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15302 Posts
Member #: 337
Fearless Tom Fenton, Avon Park 2007 & 2008 class D winner

&

TM legend.

Rotherham South Yorkshire

So what is off-boost performance like with a low c.r.? I am guessing quite slow.....but all the more fun when the turbo starts to work?


On 29th Nov, 2016 madmk1 said:


On 28th Nov, 2016 Rob Gavin said:
I refuse to pay for anything else


Like fuel 😂😂


AlexF2003

5795 Posts
Member #: 80
AFRacing LTD

Newbury, Berks

Yup...

Thats the trade off... its also harms your fuel econo, not that it should ever be a considereation with turbo minis *wink*

alex

AlexF


Tom Fenton
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15302 Posts
Member #: 337
Fearless Tom Fenton, Avon Park 2007 & 2008 class D winner

&

TM legend.

Rotherham South Yorkshire

fuel ecomony schmonony........ *happy*


On 29th Nov, 2016 madmk1 said:


On 28th Nov, 2016 Rob Gavin said:
I refuse to pay for anything else


Like fuel 😂😂


wil_h

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9258 Posts
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Post Whore

Betwix Harrogate and York

Good effort at a rhyme there Tom...

7.3:1.

Worth mentioning that the off boost power will be worse the wilder cam you have. When I had a Phase 2 fitted the engine could be off cam and off boost, with the KC500 it's only ever off boost.

Wil

Fastest 998 mini in the world? 13.05 1/4 mile 106mph



On 2nd Jan, 2013 fastcarl said:

the design shows a distinct lack of imagination,
talk about starting off with a clean sheet of paper, then not bothering to fucking draw on it,lol

On 20th Apr, 2012 Paul S said:
I'm mainly concerned about swirl in the runners caused by the tangential entry.


clubman_dan

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Winchester

i'm guessing the way to combat the sluggishness off boost is to keep the revs high betweeen gears??
DAN


AlexF2003

5795 Posts
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AFRacing LTD

Newbury, Berks

yes *happy*

AlexF


Turbo Tim

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725 Posts
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Avon Park 2006 Class D Winner

Woburn Sands

7:1

16V project underway


stuart gurr - vmaxscart

146 Posts
Member #: 350
Turboing minis since '89
Supercharging minis since '04

try to keep an area of 'squish' in the chamber ie,'D' shape chamber ,area of squish is then opposite spark plug pushing mixture towards it (and supressing detonation)- and dont make the volume between turbo and carb too big , ie,to bigger bore of intercooler pipes or too large an intercooler - lag is the time it takes to start moving and compress this volume into the engine 7.5 :1 will be good for just about anything power wise ,and its not how big the intercooler is its mainly how much air you can get through it as to how efficient it is .


AlexF2003

5795 Posts
Member #: 80
AFRacing LTD

Newbury, Berks

hello and welcome Stuart!

alex

AlexF


giallofly

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I helped keep this site alive!

4436 Posts
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The Stig..

Newport Pagnell

7.7:1 does it for me running up to 25psi.

On 21st Jan, 2011 fastcarl said:


therefore acheiving two things , a sore knob and a beer bellyl




stuart gurr - vmaxscart

146 Posts
Member #: 350
Turboing minis since '89
Supercharging minis since '04

cheers alex
don't forget i'm a junior member though!


Jimster
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9408 Posts
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455bhp per ton
12 sec 1/4 mile road legal mini

Sunny Bridgend, South Wales

I'll change that for you Stuart.

Team Racing

On 15th May, 2009 TurboDave said:

I think the welsh one has it right!


1st to provide running proof
of turbo twinkie in a car and first to
run a 1/4 in one!!

Is your data backed up?? one extra month free for all Turbo minis members, PM me for detials


AlexF2003

5795 Posts
Member #: 80
AFRacing LTD

Newbury, Berks

change mine to somthing else too Jimster!

alex

AlexF


Turbo Phil

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My sister is so fit I won't show anyone her picture

Lake District

"Nappies" has two p's in it Jim ............. *wink*

WWW.TURBO-MINI.COM


Jimster
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9408 Posts
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455bhp per ton
12 sec 1/4 mile road legal mini

Sunny Bridgend, South Wales

Cheers Phil!

What to alex?

Team Racing

On 15th May, 2009 TurboDave said:

I think the welsh one has it right!


1st to provide running proof
of turbo twinkie in a car and first to
run a 1/4 in one!!

Is your data backed up?? one extra month free for all Turbo minis members, PM me for detials


AlexF2003

5795 Posts
Member #: 80
AFRacing LTD

Newbury, Berks

dunno...

suggestions anyone?

alex

AlexF


Turbo Phil

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My sister is so fit I won't show anyone her picture

Lake District

"Fountain of knowledge" .................. ???? lol *wink*

WWW.TURBO-MINI.COM


AlexF2003

5795 Posts
Member #: 80
AFRacing LTD

Newbury, Berks

how about "The Teacher" *wink*


alex

AlexF


giallofly

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I helped keep this site alive!

4436 Posts
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The Stig..

Newport Pagnell

i must admit the Gurr/Wiffin combo gave me the turbo bug.

Jon, been turbo'in minis before most of you had pubes!

On 21st Jan, 2011 fastcarl said:


therefore acheiving two things , a sore knob and a beer bellyl




Andymini

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Senior Member

London

I've noticed that Stuarts tag says 'where in nappies' , shouldn't that read 'were in nappies' ?

Andy


Turbo Phil

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My sister is so fit I won't show anyone her picture

Lake District

Yep ! *wink*

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