my 940 aka 'the barge'

[Jim S70R]

Blimey that's some good progress you've made, polishing looks really good you should certainly be pleased with that, looking forward to the next update.

[artfulflounder]

6.5hrs spent on turbine housing so far.
Got the portal size pretty much there for the enlarged manifold.
working on the waste gate port and improving the flow to it. More flow through waste gate port and in turn reduced exhaust back pressure. Hopefully anyway.

Kept plenty of wall thickness so not gone about it like bull in a China shop.lol

Got to say it's very therapeutic.

[smithy]

Good will be nice to see the car and figuires when done .should go very well indeed matey .

[artfulflounder]

should go very well indeed matey .

Hopefully not being too optomistic but with supporting mods bear in mind its a 15g with 42lb/hr injectors would love to be anywhere mid 200s.....would just like confirmation that anything i've done has made an improvement rather than outright bhp.

if anyones interested heres some usefull info for anyone doing this first turbo swap on a redblock.

I tried to find a 13c compressor map but couldn't find one in cfm...much easier as its a constant without all the variables.So i've included a 13g which isn't too far off.

[IMG][/IMG]

Not sure of technical terms but MHI max safe PR is 2.0 (14.7 psi boost) and this equates on the plot to 360 cfm.

Now here's the 15g.

[IMG][/IMG]

At the same 14.7psi the cfm is 428.

Heres a couple of useful links:

Turbo compressor flow maps
http://www.stealth316.com/2-3s-compflowmaps.htm

And a very helpful compressor flow map calculator for cfm values at different psi and rpm levels.
http://lovehorsepower.com/joomla/ind...tuff&Itemid=49

I even managed to find some head flow figures for a stock 530 head.(taken at 28" water).

Lift Intake Exhaust
.050 24.2 17.4
.100 51.3 36.5
.150 77.8 56.4
.200 105.2 75.1
.250 129.3 89.3
.300 143.4 99.2
.350 150.4 106.5
.400 155.1 113.5
.450 159.7 118.6
.500 161.6 122.0

Don't ask me but i have next to no idea how to plot the 15g for the 940 but will try.

Anyway back to the pics.

Still loads to do yet. Need to do more work on the waste gate port and walls up to it.
Have not got as far as the wall from waste gate port to the turbine scroll yet either. whether i can improve this transition i've no idea.

Heres a pic of the unmolested housing, just a guide of the exhaust manifold exit.

[IMG][/IMG]

Comparison of work in progress and the standard 13c



This is about as far as i've got so far.As i say loads to do yet.....only taken about 8hrs on the housing alone so far.

[IMG][/IMG]

[LiamT4]

Coming along nicely.

[smithy]

Very nice write up

[LiamT4]

Sorry if I've missed this, but is it still an auto?

[wiganer31]

The 16t will fit very well, oil and water lines fit straight up, just needs clocking for rwd, but you'll have to change the down pipe flange probably.
Think it will be flat or angled. A wide band 02 would be needed to keep tabs on your fueling.

Hurry up and start on ur head so i can learn by your mistakes.lol

yea thats what im hopeing for a nice simple swap but we will see how that works out lol. ahh cheers for that i will start looking into a wide band if its something i will need, still need to look into the fueling side of things, got a set of whites and a adj fuel reg so far, i know myself round a set of spanners but this kinda stuff is abit above my head.

im not sure ive got the balls to do the head if im honest haha, you will be fine, you seem to know your stuff, hopefully you dont make no mistakes though lol, looks like your doing some good work so far! good luck

cheers

[artfulflounder]

Sorry if I've missed this, but is it still an auto?

Yes it's still an auto...With the accumulator mod and an extra external oil cooler the aw71 can cope with over 300bhp on a daily driver.

its high revs that kill them....so no more than 6300rpm ish so that'll be fine with most td04s.

[artfulflounder]

Just pre warning you that you can skip this post if not interested in maths.lol

I thought i'd try and plot my 940 for the 15g. Used the links in previous post for instructions how to use the compressor maps

[IMG][/IMG]

How much fly wheel horse power can the 15g supply....well...it takes Approximately 1 LB/MIN to support 10 flywheel horse power.
so to convert lb/min to cfm divide by 14.27. Max flow as above for the 15g is 428cfm / 14.27 = 29.99 lb/min.
Multiply this by 10 and apparently able to sustain 299.9 crank horse power.

Determining how fast a turbo will spool....now to see how fast it will spool to a certain boost level.
Left hand side of plot is pressure ratio. to determin this it is simply: Boost required + 14.7 divided by 14.7 = Pressure ratio.
so 14.7 + 14.7 / 14.7 = 2.0 Pressure ratio.

So now i want to know how quickly the turbo could potentially spool to 14.7psi. I used the calculator link in my previous post to determine cfm at any given rpm.

I entered the requested fields as below for my application.

Size of engine = 2.3
VE = 85
Maximum boost we want to hit = 14.7
Maximum engine rpm =6300
This then gives a list of flow against rpm and pressure values.

If i draw a line across the map from the 2.0 pr value it first hits the map at about 120 cfm. Using the flow calulator at 120cfm and 14.7 psi.......so apparently the 15g has potential to reach 14.7 psi at 1700 rpm on my 940.

But using the compressor map calculations again for peak figures at 6300rpm needs to flow 432.2cfm on the verge of 60% efficiency......going to be reaching the limits of the 15g.

Thats was my first attempt so don't know if these figures are anywhere near the ball park.

[T5frankie]

you wont get a 15g to 300bhp mate maybe 280 at a push

[artfulflounder]

you wont get a 15g to 300bhp mate maybe 280 at a push

Thats what i thought when i wrote it....but that is the turbo itself not necessarily in the volvo fitment.

I did look into this as i thought all the above was wrong. What i found was something like a toyota gt starlet didn't max out the flow and could quite happily run at 22psi and still be over 73% efficient.

[smithy]

Thats what i thought when i wrote it....but that is the turbo itself not necessarily in the volvo fitment.

I did look into this as i thought all the above was wrong. What i found was something like a toyota gt starlet didn't max out the flow and could quite happily run at 22psi and still be over 73% efficient.

Yes but a 2.3 redblock has got a larger displacement compared to a starlet mate .

[artfulflounder]

Yes but a 2.3 redblock has got a larger displacement compared to a starlet mate .

I know, i'm not arguing with frankie or you.

The calculation was for the approx max 15g fly wheel horse power. regardless of what car it was fitted to. was in no way implying that i could get that from the 940.

And in the case of the starlets then yes it can sustain a gnats winkey off 300.

[AndysR]

Looking good so far, you may want to get something done about the crack up to the wastegate port though as you could end up with sealing issues with the wastegate penny and this will lead to boost loss

[smithy]

I know, i'm not arguing with frankie or you.

The calculation was for the approx max 15g fly wheel horse power. regardless of what car it was fitted to. was in no way implying that i could get that from the 940.

And in the case of the starlets then yes it can sustain a gnats winkey off 300.

I'm not arguing at all mate lol .just stating that the starlets don't need a big turbo to get that amount of power .it is possible to run a 15g at 18/20psi if you got a good intercooler and the fueling of course .but it's not all about bhp its torque that you will produce .and that will be loads being an 8v .

[artfulflounder]

Looking good so far, you may want to get something done about the crack up to the wastegate port though as you could end up with sealing issues with the wastegate penny and this will lead to boost loss

Yeah I was concerned about that, but as there was no issues with previous owner I was hoping the better flow into wastegate might make life abit easier. Only going to run to 15psi.....

if it does cause issues just means I'm going to have to speed up my plans for a 3" dp and do all that work over again on a flat or angled housing.lol

[artfulflounder]

Need to get a pair of circlip pliers ordered to take the compressor housing off.

Any pointers to what I need? Size wise or what you have used.

cheers guys

[wiganer31]

i removed the circlip off two turbos easy enough with only a long reach pair of long nose pliers with a 90 deg bend in them, not ideal i know but it was all i had at the time and it worked and caused no damage, im not saying use that idea but at the time i only had access to a local hardware shop and there circlip pliers were pathetic so i just made do with what i had,


cheers

[jamesy12345]

What is the 14.7 value you are using above mate? Maybe should be 14.5