13t boost questions

[Gmstewart22]

I'm pretty sure I have the Bosch motronic 4.4 engine management system already in that car. I looked up the info off the cars vin number.

Definitely correct. All 97-98 LPT are 4.4. That's why you want to get a matched 4.4 if you drop in an HPT ECU.

[Gmstewart22]

So while we are on the topic of turbos.. is it another misconception that by installing a downpipe hou can increase boost pressure? Iv heard that it allows the turbine to spin faster this creating more boost.

[Sommerfeldt]

Thanks for fixing that - 13g, not 13t !!

Also you highlighted the wrong line in the bottom graphic ( ) - OP has an XC not a GLT. But same turbo/engine yes!

Why are you bringing up the characters "15t" here ? Not following.

Dang - I thought I was being so diligent.

The “15T” has been mentioned a few times in this thread - not by you! - and it doesn’t exist, so I thought I’d mention that as well.

- S

[Sommerfeldt]

So while we are on the topic of turbos.. is it another misconception that by installing a downpipe hou can increase boost pressure? Iv heard that it allows the turbine to spin faster this creating more boost.

A bigger downpipecan decrease backpressure from the exhaust, and let gases flow more freely. That won’t let you build more pressure - that’s controlled with the TCV and the wastegate, coupled with the size of the turbo, of course - but it will let the turbo spoil quicker. It’s helpful with a bigger, slower turbo, which otherwise would have long lag times.

Note that a down pipe, often coupled with a larger intercooler, can necessitate changes in the tune due to the airflow and characteristics of the spool-up, since it will also move the boost down through the rpm range.

- S

[Gmstewart22]

I see thanks for the information. I really like the quick spool of the 13 on the lpt cars but they just lack a little on the top end. If I could only get a 16T to spool like a 13T or 13G. The only option is to do a sequential setup small turbo for the bottom end big turbo for the top

[Gmstewart22]

To answer the above I do have a GLT as well but the car in question is as erikv11 wrote a v70 xc is the car in question..

[Sommerfeldt]

I see thanks for the information. I really like the quick spool of the 13 on the lpt cars but they just lack a little on the top end. If I could only get a 16T to spool like a 13T or 13G. The only option is to do a sequential setup small turbo for the bottom end big turbo for the top

There's always a trade-off somewhere, but I'd say a 15G might be the best compromise. It's an HPT, so you can crank it up to about 20 psi if you want, but it's petite enough to spool up pretty fast. With a larger downpipe and good breathing, you shouldn't see any lag worth worrying about with even a 16T.
I don't have a problem with lag in my car at least, on the 15G. The real noticeable lag probably starts with the 19T, but that's not an option for either yours or mine without some extensive modifications.

- S

[Gmstewart22]

I love the lag on my HPT

It gives BMWs that fleetingly second of hope, only to be dashed shortly thereafter by the back end of Moms’ station wagon.

[Gmstewart22]

Only to be dashed by the back end of moms station wagon I remember hwy racing a friend in his new v8 Lincoln LS I was driving my 850 T5. When we took off he got the hit from about 50 and by the time we hit 65 I was creaping passed him and the look on his face as an old 1995 grandmas car was making light work of his new Lincoln LS was to die for. No Joke he sold that car 2 weeks later and bought a honda cbr 800 and showed up to work and says I want a rematch! After 65mph I pulled on the Lincoln pretty quick.
In Wyoming where I lived at the time there were long straight stretches with no trees for miles, had that car up just over 150 on my GPS and she was still pulling slightly! Ever since then I've been a VOLVO fan!

[Gmstewart22]

What am I looking at cost wise for a 15g and a tune? I'm thinking I'll go for it if I can make it happen for around 2k-2.5k