300RWKW 4AGTE Turbocharger Selection

[trdee]

Again though - I can spend $1500 on a turbo and make 80kw more, or I can spend $1500 on a head and make.... 5kw more? 10kw more? 50kw more? See what im getting at here?

Also, if i were to spend money on the head, I would rather spend the money on doing a blacktop head setup than on porting a 16v

[trdee]

That squirrel performance calculator is not entirely accurate.
I say that because it does not in any way accuratly predict my 3T turbo engine with the BWS200 turbo. Neither does it precict my 350 chev twin turbo...

Their basis assumption for your 4A engine is 87% VE at full boost however at full boost an engine is usually well over 100% VE!

Try punching in the following in the S200 map: 300hp (270rwhp should be close to 300 at the fly(?)) - 12.5:1 AFR - 6000RPM peak power - 6000RPM redline - 0.6 BSFC - and the usual pumping loss and atmospheric reference.

To actually make the results mirror my dyno sheet you need to put in 120% VE - OR the BSFC needs to be dropped to 0.45 - OR some other combination of those numbers all of which are supposedly not possible in an ancient 2 valve pushrod engine according to conventional wisdom.
Now for fun try and make it all line up making peak power at 4000rpm which it does now with the blocked turbine scroll!
The exact same set of issues are present when using the Garrett instructions i.e. you have to use figures which are not commonly associated with ancient technology. The 350 chev twin turbo also needed much the same inputs to make the figures match our dyno results.
To back that up even further the results from Ford XR6 turbo engines i.e. power produced from given boost are spectacular by comparison to what either of my two engines can do so modern technology is definatly better!

My point is you have a much more efficient multi valve head there than mine and those figures that website is giving you do not necessarily accuratly reflect your engine needs.

Are there some people out there with known 4A dyno results who can pipe up with figures to help match up properly???

Cheers,
Jason

Coming back to this; if i try higher VE or lower BSFC figures as you suggested, then the GT3071R still looks like the prime contender, although I could go back to a GT2876R so long as I dont want to ever go more than 30psi boost. 30psi is juuust under the choke point of the 2876, 3071 is much more efficient though. the way the map is shaped on the 3071 makes me think it would be much more suitable for a small capacity high boost engine, whereas the 2876 looks like it is more suitable on a higher capacity lower boost engine. the efficiency islands are lower and wider on the 2876 whereas on the 3071 they are thinner and taller, giving more efficiency in the higher boost/lower flow regions

[oldeskewltoy]

cash spent vs benefit gained.... do you have any quantifiable results between your ported head and a stock head?

Again though - I can spend $1500 on a turbo and make 80kw more, or I can spend $1500 on a head and make.... 5kw more? 10kw more? 50kw more? See what im getting at here?

Also, if i were to spend money on the head, I would rather spend the money on doing a blacktop head setup than on porting a 16v

You are missing the point ENTIRELY.... it isn't the kw made... but the ability to maximize the overall builds efficiency, to allow you to run a slightly smaller turbo because the heads flow allows you to do so. This in turn allows spool-up to occur @ an even lower rpm thus allowing you more power, sooner, for longer...

[NME308]

Haha what???

You on a budget too???

I can see your point regarding the available dollars and the question of where to spend it...

If money permitted it would most definatly be a BOTH rather than either headwork OR bigger turbo however!

Cheers,
Jason

[MRMOPARMAN]

when i said "look into what the others are running"...i meant looking at the others turbos for a reference point. ie look at the maps they are running and see if it fits yours.. i didnt say 'just blind fit a turbo like theirs'.

btw if you want to minimise lag, get the head ported. yes it will make a significant difference.

edit: oh now i read your on a budget too...

so how much have/are you going to spend to minimise lag? you may as well go a blacktop head and get that fully ported, along with a 6boost/kelway manifold, so will see quite a difference to spool times, make more power, the engine will be less stressed, and turbo selection will be easier because the head will less likely to make the turbo surge (provided you have the right inlet to go on it also).

when your talking a 300wkw 1.6L.. budget doesnt really fit the sentence, if you want to do it right. so take a bit extra time to save, and do it PROPERLY!

[trdee]

I can spend 15k on an engine build if i wanted to, but i dont want to be needlessly throwing cash away either for minimal gains. Hence the qualification questions... If I wanted to spend a bomb i would just buy a lotus and be done with it....

Thanks for the flow charts OST, gives food for thought (although from what ive seen on turbo builds, a blacktop head with VVT still gives way better power under the curve and similar top end for similar money to a ported 16v head), but now lets get back to the topic of this thread, which is turbocharger selection - ive been looking for some specs and compressor maps for IHI turbos, but cant seem to find any on the web. The IHI website itself says fuckall. Can anyone shed some light on this?

[MRMOPARMAN]

lol at 'needlessly throwing money away for minimal gain'.. done right, you will be suprised at how much difference it makes. im not talking about just 'power on the dyno' shit. im talking outright power, drivability, reducing pumping losses etc etc. poerting a head on a turbo car doesnt make it a cranky high revs only think like it can sometimes do on an NA engine. it will make a real difference.

having said that you could always do it later once you have set up the car. and if someone has quoted you only $1500 to get a head fully worked, they are either crap, or they are a bloody bargain. for $1500 id be going for it!

anyways ill leave you to your big thread about turbo selection to minimise lag, then dismissing almost everyones advice..

[trdee]

ah you people crack me up...

holy shit, someone isnt just agreeing with everything i say on the internet and is actually trying to make an informed decision from a factual standpoint! what an arsehole!!

and although your comments are appreciated, this IS a thread about turbocharger selection - not how to do XYZ to my engine to get more power/less lag etc. when I want to look into that, i'll make another thread. for fucks sake....

[MRMOPARMAN]

a bit of light reading

guy does a basic port job on a 4age head.. gets good results.. SUPRISEEEEE

[trdee]

thats great, but again this is not a head/porting thread. there are plenty of threads here and elsewhere about that kinda stuff, and trust me ive read them already, and when im ready to discuss them i will make a separate thread!!!

ffs toymods tech is always like this. ask a straightforward question and get 20 people talking about how you should build a purple electric powered canoe that swims to the moon.

[jonathan yee]

a purple electric powered canoe that swims to the moon.

i want one. how do i build?

[NME308]

Trdee and me do not always see eye to eye but I can totally see where he is coming from here.

A turbo costs similar price for a 500hp unit or a 300hp unit. People have been making the kind of power old mate here is looking for with the path he is taking and on a bang for buck approach pushing a bit more air through the small hole Toyota originally supplied can work quite well. Is it the most efficient method - of course not!

Quality head work costs good money to those of us without equipment and years of experience to use it! I would have LOVED a race prepped head however money was going to be used on a turbo with or without headwork and the results I was looking for are being achieved without headwork i.e. money saved!

Carry on looking for the most efficient turbo for your application trdee.

Cheers,
Jason

[trdee]

a purple electric powered canoe that swims to the moon.

i want one. how do i build?

i dont know but i think you should possibly look at porting your head, and running inverted struts in your shocks...

Trdee and me do not always see eye to eye but I can totally see where he is coming from here.

A turbo costs similar price for a 500hp unit or a 300hp unit. People have been making the kind of power old mate here is looking for with the path he is taking and on a bang for buck approach pushing a bit more air through the small hole Toyota originally supplied can work quite well. Is it the most efficient method - of course not!

Quality head work costs good money to those of us without equipment and years of experience to use it! I would have LOVED a race prepped head however money was going to be used on a turbo with or without headwork and the results I was looking for are being achieved without headwork i.e. money saved!

Carry on looking for the most efficient turbo for your application trdee.

Cheers,
Jason

This is exactly what I am talking about Jase, thank you.

We already touched on the efficiency differences of stock to worked motors when you brought up the differences in BSFC (or VE or however other way you wanted to fudge it) and I plugged some numbers in and found that it made little difference to turbocharger selection. And seeing as this thread is about turbocharger selection, I would have thought that that would have been enough to leave such discussion to rest for the moment.. But people always get carried away with talking about other shit..... I may go with a ported head, or a blacktop head, or a completely standard head. That stuff isnt 100% set in stone yet, but this is not the place to discuss it and it bears little relevance to the aforementioned discussion. So lets drop it.

[tomvale13]

I'm eager to hear about any potential benefit that the implementation of well-placed 'speed holes' might bring to the table..

[knightrous]

I'm going to throw this out there, but have you considered twin turbo (compound turbo specifically).
There have been some good success stories of compound turbos making decent power across the whole rev range and having very little to no compromise in performance.

Food for thought
http://gearboxmagazine.com/2011/05/c...ade-it-happen/

You might be able to save a bit of cash by using some cheaper/lower performance parts together to get a good result over all. Say a KKR280 small turbo ($699) and a KKR560 large turbo ($999) together, compared to a Garret GT3071 @ $2200+.