Volumetric Efficiencies

[deejay391 0]

Im looking at a few alternatives and options on a XU10 Turbo engine.

 

Is there a easy calculation to work Actual Intake Volume fiqures out? (Im guessing there isn't) so I can then work out the VE

 

Im after the Actual Intake Volume for:

 

A 1998cc using 86mm Piston & 86mm Crank

 

Also

 

using 87mm Piston & 88mm Crank (from XU9) (is it 2044cc or 2088cc)

 

(Also im looking into the compression rations for the 87mm & 88mm hybrid...can anyone spread any light on that?)

 

Would the rods make a difference to the Actual Intake Volume? (Im guessing they would as a longer rod would increase the BDC but also increase the TDC! So will it alter the CR or cancel each other out?

 

Also would the Actual Intake Volume be altered if the Intake was pressurised? - By the turbine?

 

Im thinking out loud here and im probably getting confussed....its so simple when your reading a book Any guidance would be great

 

DJ

[Sam 4]

87mm(bore)x88mm(stroke) = 2093cc which is what I will run.

 

VE I'm not sure on. I used 95% for my calculations but it may well be more! The Graeme Bell book I got said 90-95% for a decent 4v head if I remember right.

[deejay391 0]

87mm(bore)x88mm(stroke) = 2093cc which is what I will run.

 

VE I'm not sure on. I used 95% for my calculations but it may well be more! The Graeme Bell book I got said 90-95% for a decent 4v head if I remember right.

 

Ive got

Forced Induction Performance Tuning: Bk. H691 [Hardcover] By: A.Graham Bell (Author) ISBN 1859606911

which I have yet to read, is this the book you have?

 

I've read

Street Turbocharging: Design, Fabrication, Installation, and Tuning of High-Performance Street Turbocharger Systems [Paperback]

By: Mark Warner (Author) ISBN 1557884889

- extremely good for info and told in laymans terms

 

The Street Turbocharging uses a Civic as its main 'demo' for equations. (i don't have the fiqures to hand) but if I could get the AIV then I could complete the equations and work out what psi I want to run etc

[Sam 4]

Yep thats the one I got, not too far in yet though. So far, so good.

[deejay391 0]

Cool thats the next book on my list

[deejay391 0]

Well using 95% VE

Air Intake Temp 85 F

Air Temp after Intercooling 120 F

 

 

Ive worked out

14.7psi

1.5psi losses through intercooler

88mm Crank + 87mm Pistons

300hp - ive got a feeling it was more like 400 but I didn't bring the paperwork to work

 

8psi

1.5psi losses through intercooler

86mm crank + pistons

280HP

 

Ive not got the exact figures to hand and a few fiqures i had to make a educated guess at but I think the results are resonable.

 

The only query I had was the intake temp and temp after intercooling I used examples from a book. Does anyone have and more accurate fiqures I could use instead? As i wouldn't know until I had the engine set-up and running which is a long way off im still just planning

Edited May 1, 2007 by deejay391

[Sam 4]

You'd bet that the higher CC engine will make the power lower down too.

[deejay391 0]

My thinking exactly..

 

Only one concern tho using this thread as a example

 

The varying results from using the combinations of piston diameter and crank e.g.

 

Take one iron block motor, put in a 1.9mi crank, find bearings to fit (ask hilgie) and voila 2088cc from an iron block mi motor. If i find a good 1.9mi crank its what i'll be doing.

 

 

The 1.9Mi is longstroke (83x88) but the 2.0Mi is square (86x86).

 

By putting in the 1.9Mi crank it will be longstroke again. (86x88) AND 2045cc

 

Cheers,

Hilgert

 

Now my fiquers I used a 87mm piston and 88mm crank and i've also fleeted with the idea of a XU11 crank, 2.1 as they are forged, more so for the extra cc's then the forging but I shall be looking into using those fiqures tonight. (92mm XU11D crank and 87mm bore pistons.. 2187cc..)

 

Only thing left to really get my teeth around is how to or where to find somewhere to measure the length of Rod I will need for each application

Edited May 1, 2007 by deejay391

[Sam 4]

I was going to try and find a forged 86mm crank (btcc) but i'll probably stay 88mm now, we'll see. Like I say, revs would be nice.

 

The standard S16 rod is 152mm. Mine are 152.4mm so need some work on other bits to make it all work out, the pistons are designed with the 88mm stroke in mind.

[deejay391 0]

I was going to try and find a forged 86mm crank (btcc) but i'll probably stay 88mm now, we'll see. Like I say, revs would be nice.

 

The standard S16 rod is 152mm. Mine are 152.4mm so need some work on other bits to make it all work out, the pistons are designed with the 88mm stroke in mind.

 

Ive got to work out the compression stroke using the standard rods and then play around with the rod length....then get them made up using some standard 87mm pistons...i think Omega pistons are 87mm just got to see if they are suitable, im hoping its that easy anyway. Its more a trial and error project really so keeping costs down and sourcing 'standard' parts is the name of the game before I then find what works and replace all for new custom bits....prob won't work that way but it'll be a learning curve if nothing else

[James_R 3]

to keep costs down I'd look at using 2L turbo Vx pistons, can be sourced for £50 or so, that shoudl bring you down to a sensiblish CR then a slightly thicker H/G depends if you want to push the boat out and spend lots.

 

On the balance of things, it's probabaly better to put the money in to the ECU than a mega spec'd bottom end as you can always add a little extra boost to knock it up if you want, but drivablitly is the name of the game??

[deejay391 0]

to keep costs down I'd look at using 2L turbo Vx pistons, can be sourced for £50 or so, that shoudl bring you down to a sensiblish CR then a slightly thicker H/G depends if you want to push the boat out and spend lots.

 

On the balance of things, it's probabaly better to put the money in to the ECU than a mega spec'd bottom end as you can always add a little extra boost to knock it up if you want, but drivablitly is the name of the game??

 

I was waiting for you to see this thread

 

I thought there was a few Vauxhall parts that could be utilised, a crank as well I think is useable. I'll have to look into the Vx specs, got any to hand??

 

Theres 2 options on management and thats megasquirt and Emerald, my mapper prefers Emerald and i've heard a few difficult tales on megasquirt but again as this is a learning curve I should really go megasquirt but then again that maybe a step too far...

[James_R 3]

migweb's search button will guide you, or www.maxboost.com/co.uk is pretty handy too.

 

I'd run what ever your mapper tells you to, as the mapping is the bit which makes it all work, poor map and you'd be fixing it all the time or it will drive poorly no matter what shinee bits you put on it

[Sam 4]

Ive got to work out the compression stroke using the standard rods and then play around with the rod length....then get them made up using some standard 87mm pistons...i think Omega pistons are 87mm just got to see if they are suitable, im hoping its that easy anyway. Its more a trial and error project really so keeping costs down and sourcing 'standard' parts is the name of the game before I then find what works and replace all for new custom bits....prob won't work that way but it'll be a learning curve if nothing else

 

Get some wiseco's like mine? I still have the part number (well Sandy has it I think??) or I could give you the contact for the guy in the states who made them. Not sure if they ship to the uk though :s

[petert 585]

I can organise Wiseco pistons if desired. I've just done a set of 87mm, 23mm full floating pin pistons to suit a 92mm stroke for DrSarty at a very attractive price.

[Sam 4]

Wish I'd gone for the 23mm pin I'm on 22mm I *think*

Edited May 4, 2007 by Sam