GrantMC2

All, help please.

I have the chance to get the below pic'd turbo rather cheap.

I worry though, that its too small .. Specs can be seen in the pics but here is a break down.

T3 (I think, can someone confirm?)
AR 0.42

Thats about all i can deduce .. Any input would be great .. This is to go on a B18C4 (your B18C1 equivalent) Is this turbo going to run out of puff uptop?

Thanks,

wantboost

iTrader: (2)

It's not a T3, it's a t25 off of an older Saab. It's horribly small for your setup and will have virtually no top end. It's good for maybe, MAYBE, 200-215hp at its absolute limit running no more than 14psi. After 14psi all it does it is increase air temps with a sharp dropoff in efficiency plus the turbo would be dangerously close to its shaft speed limit. Although iirc the Saab t25 turbo was smaller than your typical Garrett/sr20 t25 which were good for about 215hp@14psi so this might not even make 200

The small turbine wheel and housing are going to kill the efficiency, economy, and performance of the motor. At higher rpm the back pressure in the manifold before the turbine is going to kill power, torque, fuel economy, cause elevated EGTs, and so on. You might even see a drop in power at high rpm below what it was making NA, this is due to the motor using more airflow than the turbo can deliver but the pre turbine back pressure will prevent the motor from breathing like it should. If the motor can't get the air out (exhaust stroke) then it can't get the air in (intake stroke), you might even see some reversion where exhaust gasses stay in the cylinder during the next intake stroke (think of it as accidental EGR) causing a further decrease in power and efficiency.

Now you could aim for a hyper mileage setup with this turbo. Keep boost pressures low, get a rock solid tune, and don't rev the motor out above where power drops off in addition to not driving like a jackass and you can see a decent increase in fuel economy. Think of it like an OEM turbo application, say for example fords ecoboost motors, they use small turbos at moderate pressure levels for very fast response very low in the rpm range. This lets the motor produce high torque output at low rpm and light throttle inputs, this eliminates the need to excessively rev the motor and to use heavy throttle inputs. All of this works together to lower fuel flow demands which in turn translates to higher fuel economy.

But if you're going to try and use this in a performance application don't waste your time. It would probably be a good "street" turbo for a single cam d15 but that's about it.

GrantMC2

You dear sir, have been a massive help. Thank you for taking the time to reply. Much appreciated.

I will, bin the idea off!

wantboost

iTrader: (2)

That's what I'm here for. If you need any further help with a turbo selection don't hesitate to PM me, there isn't much about turbochargers that I don't know lol.

If you already have the turbo and it's in decent shape toss it on eBay. From the photos it appears to be super clean, housings are exceptionally clean given its age, typically you'll see them with filthy compressor housings and rusted turbine housings with lots of heat cracks around the wastegate port. The wheels look great as well, no signs of oxidation or oil and crud build up. Plus the billet wastegate actuator is not an OEM piece and tells me whoever had this turbo before used it in more of a perfoance oriented application and took exceptionally good care of it with proper maintenance. With good pictures and description there's no reason it shouldn't sell for a couple hundred dollars. If you're on the homemade turbo forums you could list it there, a lot of non vtec d series guys on there love t25s for builds. You could even spend 100 dollars on a drop in billet upgrade wheel, do a little DIY porting on the turbine housing with a dremel tool and sell it for even more to the right person, granted that could also backfire horribly.

Hell if I weren't flat broke (literally) I might be interested in it. I'm a turbo collector of sorts (22 at the moment) and always keep an eye out for turbos in good shape.

GrantMC2

Again mate, I appreciate it.. And I may well take you up on the offer. Although I've spent some time researching and pick things up reasonably quickly, I'm still not as queued up as I'd like before making the decision yet!

22 ?!?!?! Wow . I only want one! However, sending it all the way to you might be an issue ;-) I'm in the UK ..

It's kind of in limbo at the moment, the friend i was "purchasing" it from doesnt really want in back. We'll see what he says in a couple of weeks. He's just dumped off a load of stuff that he doesnt want to store!