300RWKW 4AGTE Turbocharger Selection

[RONA]

Surely space & heat from a twin turbo setup would be a major issue especially in an Adub. It also means new manifold, new dump pipes, new intercooler piping etc etc which would blow out past building the head costs.

[knightrous]

Depending on the placement of his current manfold, he could mount the small turbo onto it, then mount the large turbo off the back of the small turbo exhaust housing.

[RONA]

Having seen the shit fight to fit the current setup in it has no hope in hell of fitting.

[jonathan yee]

A.gt3071 will cost less than 2.2k, not entirely familiar with the compound setup but at a guess the extra fabrication will equal the gt3071 at least I reckon?

[trdee]

GT3071R is only a bit over 1500 from GCG (who are not known for being cheap) including a ceramic coated exhaust housing.

and not a chance in hell i am going compound turbo. No, no, fucking mother of God no.

[knightrous]

I just googled it up and found http://www.horsepowerinabox.com/HPIAB2/category12_2.htm
GT3071 Ball bearing turbo = $2250 >.>

[RONA]

Stupidly expensive I think I paid around that for my GTX3076r through GCG which included V Band housing & ceramic coating.

[NME308]

...and not a chance in hell i am going compound turbo. No, no, fucking mother of God no.

I'd do it in a heartbeat if room were not an issue! My S200sx blowing into a GT2560 both at 2:1 pressure ratio. Power band would be 2200rpm to engine grenade 7500rpm - only havn't done it in one of my fits of boredom because I'm quite convinced my humble carb would not have a snowflakes chance in hell of metering fuel over the humongous range required...

Twin compounded turbo big bore small stroke chev V8 sitting in my shed waiting to be assembled - but thats because I have room in a drag barge unlike an adub!

Cheers,
Jason

[trdee]

1) dont need full boost at 2000rpm. if anything, full boost at that many rpm will just make the car more undrivable, not less. The way that power comes on at the moment actually makes the car easier to drive than when it had almost half the power in supercharged guise, as i can plant it on corner exit, set myself up nicely and then the power kicks in. Rather than just jumping to the rear tyres all at once.

2) it wont fit in the engine bay nicely, if at all. no fucking chance.

Garrett GT3071R-56T-T3 with 4" entry is $1485 from GCG
http://www.gcg.com.au/index.php?page...mart&Itemid=53

add 0.63AR Vband rear housing = $29.70
add ceramic coated rear housing = $185

Total = $1699.70

Thats a fair bit less than 2.2k+

[RT40Corona4AGTE]

Can i suggest taking a look at the Precision turbocharger range? I looked at maps a year or so ago when I chose mine (5557SP) and I liked them.

You may have to email them again to get a copy of their maps though? I cant seem to find the one's I had when I made my decision.

Just a suggestion. I like the data this thread is compiling though, keep up the good conversations on "turbo selection" people! :-)

[boxh34d]

trdee:
Whilst I completely understand where your coming from with trying to keep this on topic to turbo selection (only), I think you should give the suggestions from OST and others suggesting porting some serious thought. As you've seen, you are very limited in turbo choice to make the HP numbers with enough meat in the top left of the map to not surge like a mofo. This makes the idea of choosing a turbo based on some guesses very hard due to the very narrow safety margin at those higher PR's. Also, to make this kind of power, you'll need your engine to still be able to breath well enough to be making power and falling off at 8500rpm. My thought is that porting will go a long way to helping achieve this.
If you can increase your higher rev VE through porting and cam selection, it may allow you to make your desired power at 5psi less boost, which opens up a lot more turbo choice, and might make all the difference between having an engine / turbo package that is right, compared with one that is very, very wrong.

FWIW, porting or no porting, I'd choose the GTX3071R or even the GT3076R over the plain GT3071R for the higher efficiency, and the ability to move 50lb/min without overspeeding it, which I think may prove very benificial in your case. The map is considerably wider in the higher PR's, and by my guess is you'd need around 35lb/min @ 6000rpm, and close to 50lb/min @8500rpm - provided that you can still make power at this rpm. Have a look at those points on both the maps and compare them.

[oldcorollas]

goddamit.. in google image search, these look slike compressor maps http://www.ihi-kenki.co.jp/japanese/...cch650_do2.gif

if you are going down headwork route, just get blacktop, better base, better potential, less farking around


IHI maps (and shitloads of others.. hth)
comparison, then specs, then individual maps for 3911 and 4016
http://www.not2fast.com/turbo/maps/all.html#ihi

[NME308]

1) ...as i can plant it on corner exit...

'Corner' - I did a quick google search and came up with this: a difficult or embarrassing situation : a position from which escape or retreat is difficult or impossible <was backed into a corner>

I suspect upon further investigation this may be what you refer to?


My bad I keep forgetting some of you folks have access to racing circuits where melting tires at the toenail touch of throttle is not entirely desirable!

Cheers,
Jason

[oldcorollas]

more........

http://www.rexnet.com.au/forum/index...-vf24-vs-vf29/

a few randoms here
http://www.stealth316.com/2-3s-compflowmaps.htm
IHI RHF55 http://www.stealth316.com/images/rhf55-cfm.gif

[trdee]

I dont mean to dismiss the other guys' suggestions as useless, but they are somewhat irrelevant as their suggestions are already covered by what NME308 was saying in terms of the changes to either VE or BSFC to get more "real world" values of a worked motor on those plots.

The problem that I now see is how far do I go with fudging VE and BSFC figures?

I can use fandio's motor as a reference for a "worked engine" - 8.9:1 gze bottom end, stock blacktop head, 228rwkw at 17psi
And I can use my motor as a reference for a "standard engine" - 8:1 gze bottom end, stock bigport head, 180rwkw at 17psi

I need to drop BSFC to 0.41 to get the boost VS power figures to match fandio's real world results. Doing that drops the air flow to 17lb/min at peak, which is obviously wrong.

On the contrary, if I take the VE values from fandio's adaptronic file, he has a peak power VE of 164%, peak boost VE of 158% and 3000rpm minimum boost VE of 68%. Plugging those into the calculator requires BSFC to go up to like 0.75 to get the right power/boost ratio, and air flow goes up into the 55lb/min mark for just 340 engine HP, again obviously wrong. Although his values dont seem to add up with mine, at peak power I am only at 103% VE. And we dont have that much difference in power to warrant such a VE change I wouldnt think.

So, what I need to do is fudge both VE and BSFC at the same time to get a realistic figure of air flow as well as power VS boost. To do this, I need a figure for air flow to aim for. I can use fandio's engine (or mine) as relations for peak power VS boost, but I have no figures for air flow.... boxhe4d recommends 50lb/min for 300rwkw, can anyone else suggest some figures or show me how to calculate them?

edit; OC i agree on the blacktop head route if i were to do head work.... but that doesnt mean i am going to do any headwork at all necessarily. I havent decided yet. At the moment from what I can see the best bang for buck is to just slap some kelford turbo cams in a stock smallport head and leave it at that.. but that is discussion for another thread

Also thanks for the IHI links