I have limited understanding on turbos; so bear with.


I have an S4 turbo on my car. It burns oil... pretty badly. I need to rebuild it, but I like driving my car. For example I drive 10 miles to work each day, but I live a block away from work. So I want to put a turbo together and drop it in the same day as apposed to waiting for parts and having a car sit without being used.

I have an S5 turbo and an S4 exhaust side. Can I put new seals and guts into the S5 turbo and mate it to the S4 exhaust housing? I don't know if I'm using the proper lingo.

Part of me just wants to hunt down an S5 exhaust manifold, but part of me wants to explore with a mutant turbo. I'm just curious if anybody's done it.

 

Late S4 CHRA will fit into S5 exhaust housing. I've done it. It works fine.

Early S4 won't work like that. Early has two heat shields with a deeper machined groove. Late S4 and all S5 have a single heat shield and thus are compatible.

 

the S4 and S5 turbo use the same wheels, and except for that variation in the cartridge that jeff pointed out, the only real difference is the exhaust housing and manifold.

 

what is your guys' peak hp and spool time, i've been looking at using an HT12 from half a stock twin setup. spool would be at around 2200 rpm(pressure reached, not starting). and they are descent up to 17 psi.( about 220 hp max)
to me the ht15 is a 3k spooler to make 250 at 14 psi( 14-15 is about the useful limit of the ht 15. but the 12 goes abit higher.)

i also have a volvo s70 turbo- td05-13g i think....that is just slightly bigger then the HT12( measuring the exhuast inducer and exducer was about 10 percent more then the ht 12... but this td05 has built in wastegate AND BOV like newer EFR turbos. thinking the TD05 may spool the same or better then the ht12.

the point i am making it maybe lets step away from 88 turbos and look what 2002 oem turbos, like those from volvo and Mitsubishi. newer turbos, newer tech, better performance.....

for the OP ... putting on anything other then the stock FC turbo in your case is going to be more then a days labor. putting the turbo on is the easy part, but when none of the oil/ coolant lines match up.. it takes a few days.

 

i looked into the volvo turbos a bit, and i do like that there are quite a few choices for turbos and wheels, i think you could have a stock based turbo that made more power, but still had stock spool.

the thing is though that the volvo engine is a piston engine, and thus its quite lazy, on a rotary a TD05-13G is good for 243.75hp max, at the flywheel, which is why the rotary people run two of them.

 

I just ordered an S4 turbo and manifold from eBay. The price was right so I went for it. I don't know if this is an early or late model.

I haven't done much with any S4 turbos yet so we'll see how things go.

 

Yeah, I don't know what that all means in the first few paragraphs. But it sounds like fun if you enjoy plumbing and all kinds of work.



What kinda rebuild kit does the stock FC turbo use? I heard it was a Garret turbo of some kind.

 

I don't remember where I got mine from, but they have them on ebay for like 39-69$

 

Hitachi HT18 Complete Rebuild Kit |

 

That's where I got my rebuild kit from, I couldn't think of it for the life of me. They have fast shipping also

 

thats why i compared them to the ht12. two ht 12s are good for 400rwhp max,all stars aligned.

i'm only wanted to make 180-200hp. i want spool time. i want full boost at 2.5k rpm.

the ht12 by itself can do this, but i'm gonna run the td05as it's a cunthair bigger.

 

Related to this thread, so bear with me.

For those who have rebuilt FC turbos, do you find it worth the extra $40 to go with the 360 thrust bearing and step gap piston ring in the rebuild? I plan on doing it to my hybrid turbo rebuild in a month, just wondering for my sake and the sake of the OP.

 

if you're just running stock boost, stock is probably ok. if you're going to run more boost, turbo RPM's will be higher, so anything you can do to make the turbo last longer is good

 

OK cool, thanks for the advice. I'm turning the boost up in my build with the Rtek 2.1, hybrid turbo, 3" exhaust, blah blah blah...won't clutter up the thread.

So it's a good idea to spend the extra money up front, got it

 

I've stuck with the stock 270 degrees bearing and carbon seal. So far it seems to work fine at like 9psi or so.

Oh and the S4 turbo arrived. Looks to be in good shape. I wonder whether it's a late or early model. Is there any way to tell other than just separating the exhaust housing from the CHRA?

 

basically the turbo moves a certain amount of air at a certain shaft RPM, lets just say a stock T2 turbo moves 200airs at 110,000rpm, and this makes 200hp on an FC engine.

to make 250hp the turbo needs to move 250 airs, the turbo either needs to be bigger or spin faster. since 110k is already really high, we see that the turbos wear quickly.

the hybrid turbos use a bigger fan, and we'll say it moves 250 airs at 110k shaft speed. so reliability stays similar to stock, but hp goes up.

i'm over simplifying a bit, but the shaft speeds are mentioned in the FSM's, we could also calculate a real cfm number, but to make the point the fake one works ok

 

When I need more than 200HP, I'll think about doing a hybrid. But for now, 200 is plenty. I think it hits full boost by 3000 in 2nd gear. Plenty for me.

 

but what if the spool was 10 psi at 2000 rpm. i drive this and i can tell you the difference is amazing, and from 2500-4500 rpm you can have 220-240 ftlbs of torque. i dont think mine quite there, but i got a few more then things to get THAT turbo setup sorted.. after it dynos the 12a turbo should be ready with it's volvo turbo...

 

here is my volvo compress or map, its a td04. i can upgrate later to a new chra and 19t compressor/ housing.